cregit-Linux how code gets into the kernel

Release 4.13 block/cfq-iosched.c

Directory: block
/*
 *  CFQ, or complete fairness queueing, disk scheduler.
 *
 *  Based on ideas from a previously unfinished io
 *  scheduler (round robin per-process disk scheduling) and Andrea Arcangeli.
 *
 *  Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
 */
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sched/clock.h>
#include <linux/blkdev.h>
#include <linux/elevator.h>
#include <linux/ktime.h>
#include <linux/rbtree.h>
#include <linux/ioprio.h>
#include <linux/blktrace_api.h>
#include <linux/blk-cgroup.h>
#include "blk.h"
#include "blk-wbt.h"

/*
 * tunables
 */
/* max queue in one round of service */

static const int cfq_quantum = 8;

static const u64 cfq_fifo_expire[2] = { NSEC_PER_SEC / 4, NSEC_PER_SEC / 8 };
/* maximum backwards seek, in KiB */

static const int cfq_back_max = 16 * 1024;
/* penalty of a backwards seek */

static const int cfq_back_penalty = 2;

static const u64 cfq_slice_sync = NSEC_PER_SEC / 10;

static u64 cfq_slice_async = NSEC_PER_SEC / 25;

static const int cfq_slice_async_rq = 2;

static u64 cfq_slice_idle = NSEC_PER_SEC / 125;

static u64 cfq_group_idle = NSEC_PER_SEC / 125;

static const u64 cfq_target_latency = (u64)NSEC_PER_SEC * 3/10; 
/* 300 ms */

static const int cfq_hist_divisor = 4;

/*
 * offset from end of queue service tree for idle class
 */

#define CFQ_IDLE_DELAY		(NSEC_PER_SEC / 5)
/* offset from end of group service tree under time slice mode */

#define CFQ_SLICE_MODE_GROUP_DELAY (NSEC_PER_SEC / 5)
/* offset from end of group service under IOPS mode */

#define CFQ_IOPS_MODE_GROUP_DELAY (HZ / 5)

/*
 * below this threshold, we consider thinktime immediate
 */

#define CFQ_MIN_TT		(2 * NSEC_PER_SEC / HZ)


#define CFQ_SLICE_SCALE		(5)

#define CFQ_HW_QUEUE_MIN	(5)

#define CFQ_SERVICE_SHIFT       12


#define CFQQ_SEEK_THR		(sector_t)(8 * 100)

#define CFQQ_CLOSE_THR		(sector_t)(8 * 1024)

#define CFQQ_SECT_THR_NONROT	(sector_t)(2 * 32)

#define CFQQ_SEEKY(cfqq)	(hweight32(cfqq->seek_history) > 32/8)


#define RQ_CIC(rq)		icq_to_cic((rq)->elv.icq)

#define RQ_CFQQ(rq)		(struct cfq_queue *) ((rq)->elv.priv[0])

#define RQ_CFQG(rq)		(struct cfq_group *) ((rq)->elv.priv[1])


static struct kmem_cache *cfq_pool;


#define CFQ_PRIO_LISTS		IOPRIO_BE_NR

#define cfq_class_idle(cfqq)	((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE)

#define cfq_class_rt(cfqq)	((cfqq)->ioprio_class == IOPRIO_CLASS_RT)


#define sample_valid(samples)	((samples) > 80)

#define rb_entry_cfqg(node)	rb_entry((node), struct cfq_group, rb_node)

/* blkio-related constants */

#define CFQ_WEIGHT_LEGACY_MIN	10

#define CFQ_WEIGHT_LEGACY_DFL	500

#define CFQ_WEIGHT_LEGACY_MAX	1000


struct cfq_ttime {
	
u64 last_end_request;

	
u64 ttime_total;
	
u64 ttime_mean;
	
unsigned long ttime_samples;
};

/*
 * Most of our rbtree usage is for sorting with min extraction, so
 * if we cache the leftmost node we don't have to walk down the tree
 * to find it. Idea borrowed from Ingo Molnars CFS scheduler. We should
 * move this into the elevator for the rq sorting as well.
 */

struct cfq_rb_root {
	
struct rb_root rb;
	
struct rb_node *left;
	
unsigned count;
	
u64 min_vdisktime;
	
struct cfq_ttime ttime;
};

#define CFQ_RB_ROOT	(struct cfq_rb_root) { .rb = RB_ROOT, \
                        .ttime = {.last_end_request = ktime_get_ns(),},}

/*
 * Per process-grouping structure
 */

struct cfq_queue {
	/* reference count */
	
int ref;
	/* various state flags, see below */
	
unsigned int flags;
	/* parent cfq_data */
	
struct cfq_data *cfqd;
	/* service_tree member */
	
struct rb_node rb_node;
	/* service_tree key */
	
u64 rb_key;
	/* prio tree member */
	
struct rb_node p_node;
	/* prio tree root we belong to, if any */
	
struct rb_root *p_root;
	/* sorted list of pending requests */
	
struct rb_root sort_list;
	/* if fifo isn't expired, next request to serve */
	
struct request *next_rq;
	/* requests queued in sort_list */
	
int queued[2];
	/* currently allocated requests */
	
int allocated[2];
	/* fifo list of requests in sort_list */
	
struct list_head fifo;

	/* time when queue got scheduled in to dispatch first request. */
	
u64 dispatch_start;
	
u64 allocated_slice;
	
u64 slice_dispatch;
	/* time when first request from queue completed and slice started. */
	
u64 slice_start;
	
u64 slice_end;
	
s64 slice_resid;

	/* pending priority requests */
	
int prio_pending;
	/* number of requests that are on the dispatch list or inside driver */
	
int dispatched;

	/* io prio of this group */
	

unsigned short ioprio, org_ioprio;
	

unsigned short ioprio_class, org_ioprio_class;

	
pid_t pid;

	
u32 seek_history;
	
sector_t last_request_pos;

	
struct cfq_rb_root *service_tree;
	
struct cfq_queue *new_cfqq;
	
struct cfq_group *cfqg;
	/* Number of sectors dispatched from queue in single dispatch round */
	
unsigned long nr_sectors;
};

/*
 * First index in the service_trees.
 * IDLE is handled separately, so it has negative index
 */

enum wl_class_t {
	
BE_WORKLOAD = 0,
	
RT_WORKLOAD = 1,
	
IDLE_WORKLOAD = 2,
	
CFQ_PRIO_NR,
};

/*
 * Second index in the service_trees.
 */

enum wl_type_t {
	
ASYNC_WORKLOAD = 0,
	
SYNC_NOIDLE_WORKLOAD = 1,
	
SYNC_WORKLOAD = 2
};


struct cfqg_stats {
#ifdef CONFIG_CFQ_GROUP_IOSCHED
	/* number of ios merged */
	
struct blkg_rwstat		merged;
	/* total time spent on device in ns, may not be accurate w/ queueing */
	
struct blkg_rwstat		service_time;
	/* total time spent waiting in scheduler queue in ns */
	
struct blkg_rwstat		wait_time;
	/* number of IOs queued up */
	
struct blkg_rwstat		queued;
	/* total disk time and nr sectors dispatched by this group */
	
struct blkg_stat		time;
#ifdef CONFIG_DEBUG_BLK_CGROUP
	/* time not charged to this cgroup */
	
struct blkg_stat		unaccounted_time;
	/* sum of number of ios queued across all samples */
	
struct blkg_stat		avg_queue_size_sum;
	/* count of samples taken for average */
	
struct blkg_stat		avg_queue_size_samples;
	/* how many times this group has been removed from service tree */
	
struct blkg_stat		dequeue;
	/* total time spent waiting for it to be assigned a timeslice. */
	
struct blkg_stat		group_wait_time;
	/* time spent idling for this blkcg_gq */
	
struct blkg_stat		idle_time;
	/* total time with empty current active q with other requests queued */
	
struct blkg_stat		empty_time;
	/* fields after this shouldn't be cleared on stat reset */
	
uint64_t			start_group_wait_time;
	
uint64_t			start_idle_time;
	
uint64_t			start_empty_time;
	
uint16_t			flags;
#endif	/* CONFIG_DEBUG_BLK_CGROUP */
#endif	/* CONFIG_CFQ_GROUP_IOSCHED */
};

/* Per-cgroup data */

struct cfq_group_data {
	/* must be the first member */
	
struct blkcg_policy_data cpd;

	
unsigned int weight;
	
unsigned int leaf_weight;
};

/* This is per cgroup per device grouping structure */

struct cfq_group {
	/* must be the first member */
	
struct blkg_policy_data pd;

	/* group service_tree member */
	
struct rb_node rb_node;

	/* group service_tree key */
	
u64 vdisktime;

	/*
         * The number of active cfqgs and sum of their weights under this
         * cfqg.  This covers this cfqg's leaf_weight and all children's
         * weights, but does not cover weights of further descendants.
         *
         * If a cfqg is on the service tree, it's active.  An active cfqg
         * also activates its parent and contributes to the children_weight
         * of the parent.
         */
	
int nr_active;
	
unsigned int children_weight;

	/*
         * vfraction is the fraction of vdisktime that the tasks in this
         * cfqg are entitled to.  This is determined by compounding the
         * ratios walking up from this cfqg to the root.
         *
         * It is in fixed point w/ CFQ_SERVICE_SHIFT and the sum of all
         * vfractions on a service tree is approximately 1.  The sum may
         * deviate a bit due to rounding errors and fluctuations caused by
         * cfqgs entering and leaving the service tree.
         */
	
unsigned int vfraction;

	/*
         * There are two weights - (internal) weight is the weight of this
         * cfqg against the sibling cfqgs.  leaf_weight is the wight of
         * this cfqg against the child cfqgs.  For the root cfqg, both
         * weights are kept in sync for backward compatibility.
         */
	
unsigned int weight;
	
unsigned int new_weight;
	
unsigned int dev_weight;

	
unsigned int leaf_weight;
	
unsigned int new_leaf_weight;
	
unsigned int dev_leaf_weight;

	/* number of cfqq currently on this group */
	
int nr_cfqq;

	/*
         * Per group busy queues average. Useful for workload slice calc. We
         * create the array for each prio class but at run time it is used
         * only for RT and BE class and slot for IDLE class remains unused.
         * This is primarily done to avoid confusion and a gcc warning.
         */
	
unsigned int busy_queues_avg[CFQ_PRIO_NR];
	/*
         * rr lists of queues with requests. We maintain service trees for
         * RT and BE classes. These trees are subdivided in subclasses
         * of SYNC, SYNC_NOIDLE and ASYNC based on workload type. For IDLE
         * class there is no subclassification and all the cfq queues go on
         * a single tree service_tree_idle.
         * Counts are embedded in the cfq_rb_root
         */
	
struct cfq_rb_root service_trees[2][3];
	
struct cfq_rb_root service_tree_idle;

	
u64 saved_wl_slice;
	
enum wl_type_t saved_wl_type;
	
enum wl_class_t saved_wl_class;

	/* number of requests that are on the dispatch list or inside driver */
	
int dispatched;
	
struct cfq_ttime ttime;
	
struct cfqg_stats stats;	/* stats for this cfqg */

	/* async queue for each priority case */
	
struct cfq_queue *async_cfqq[2][IOPRIO_BE_NR];
	
struct cfq_queue *async_idle_cfqq;

};


struct cfq_io_cq {
	
struct io_cq		icq;		/* must be the first member */
	
struct cfq_queue	*cfqq[2];
	
struct cfq_ttime	ttime;
	
int			ioprio;		/* the current ioprio */
#ifdef CONFIG_CFQ_GROUP_IOSCHED
	
uint64_t		blkcg_serial_nr; /* the current blkcg serial */
#endif
};

/*
 * Per block device queue structure
 */

struct cfq_data {
	
struct request_queue *queue;
	/* Root service tree for cfq_groups */
	
struct cfq_rb_root grp_service_tree;
	
struct cfq_group *root_group;

	/*
         * The priority currently being served
         */
	
enum wl_class_t serving_wl_class;
	
enum wl_type_t serving_wl_type;
	
u64 workload_expires;
	
struct cfq_group *serving_group;

	/*
         * Each priority tree is sorted by next_request position.  These
         * trees are used when determining if two or more queues are
         * interleaving requests (see cfq_close_cooperator).
         */
	
struct rb_root prio_trees[CFQ_PRIO_LISTS];

	
unsigned int busy_queues;
	
unsigned int busy_sync_queues;

	
int rq_in_driver;
	
int rq_in_flight[2];

	/*
         * queue-depth detection
         */
	
int rq_queued;
	
int hw_tag;
	/*
         * hw_tag can be
         * -1 => indeterminate, (cfq will behave as if NCQ is present, to allow better detection)
         *  1 => NCQ is present (hw_tag_est_depth is the estimated max depth)
         *  0 => no NCQ
         */
	
int hw_tag_est_depth;
	
unsigned int hw_tag_samples;

	/*
         * idle window management
         */
	
struct hrtimer idle_slice_timer;
	
struct work_struct unplug_work;

	
struct cfq_queue *active_queue;
	
struct cfq_io_cq *active_cic;

	
sector_t last_position;

	/*
         * tunables, see top of file
         */
	
unsigned int cfq_quantum;
	
unsigned int cfq_back_penalty;
	
unsigned int cfq_back_max;
	
unsigned int cfq_slice_async_rq;
	
unsigned int cfq_latency;
	
u64 cfq_fifo_expire[2];
	
u64 cfq_slice[2];
	
u64 cfq_slice_idle;
	
u64 cfq_group_idle;
	
u64 cfq_target_latency;

	/*
         * Fallback dummy cfqq for extreme OOM conditions
         */
	
struct cfq_queue oom_cfqq;

	
u64 last_delayed_sync;
};

static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd);
static void cfq_put_queue(struct cfq_queue *cfqq);


static struct cfq_rb_root *st_for(struct cfq_group *cfqg, enum wl_class_t class, enum wl_type_t type) { if (!cfqg) return NULL; if (class == IDLE_WORKLOAD) return &cfqg->service_tree_idle; return &cfqg->service_trees[class][type]; }

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enum cfqq_state_flags { CFQ_CFQQ_FLAG_on_rr = 0, /* on round-robin busy list */ CFQ_CFQQ_FLAG_wait_request, /* waiting for a request */ CFQ_CFQQ_FLAG_must_dispatch, /* must be allowed a dispatch */ CFQ_CFQQ_FLAG_must_alloc_slice, /* per-slice must_alloc flag */ CFQ_CFQQ_FLAG_fifo_expire, /* FIFO checked in this slice */ CFQ_CFQQ_FLAG_idle_window, /* slice idling enabled */ CFQ_CFQQ_FLAG_prio_changed, /* task priority has changed */ CFQ_CFQQ_FLAG_slice_new, /* no requests dispatched in slice */ CFQ_CFQQ_FLAG_sync, /* synchronous queue */ CFQ_CFQQ_FLAG_coop, /* cfqq is shared */ CFQ_CFQQ_FLAG_split_coop, /* shared cfqq will be splitted */ CFQ_CFQQ_FLAG_deep, /* sync cfqq experienced large depth */ CFQ_CFQQ_FLAG_wait_busy, /* Waiting for next request */ }; #define CFQ_CFQQ_FNS(name) \ static inline void cfq_mark_cfqq_##name(struct cfq_queue *cfqq) \ { \ (cfqq)->flags |= (1 << CFQ_CFQQ_FLAG_##name); \ } \ static inline void cfq_clear_cfqq_##name(struct cfq_queue *cfqq) \ { \ (cfqq)->flags &= ~(1 << CFQ_CFQQ_FLAG_##name); \ } \ static inline int cfq_cfqq_##name(const struct cfq_queue *cfqq) \ { \ return ((cfqq)->flags & (1 << CFQ_CFQQ_FLAG_##name)) != 0; \ } CFQ_CFQQ_FNS(on_rr); CFQ_CFQQ_FNS(wait_request); CFQ_CFQQ_FNS(must_dispatch); CFQ_CFQQ_FNS(must_alloc_slice); CFQ_CFQQ_FNS(fifo_expire); CFQ_CFQQ_FNS(idle_window); CFQ_CFQQ_FNS(prio_changed); CFQ_CFQQ_FNS(slice_new); CFQ_CFQQ_FNS(sync); CFQ_CFQQ_FNS(coop); CFQ_CFQQ_FNS(split_coop); CFQ_CFQQ_FNS(deep); CFQ_CFQQ_FNS(wait_busy); #undef CFQ_CFQQ_FNS #if defined(CONFIG_CFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP) /* cfqg stats flags */ enum cfqg_stats_flags { CFQG_stats_waiting = 0, CFQG_stats_idling, CFQG_stats_empty, }; #define CFQG_FLAG_FNS(name) \ static inline void cfqg_stats_mark_##name(struct cfqg_stats *stats) \ { \ stats->flags |= (1 << CFQG_stats_##name); \ } \ static inline void cfqg_stats_clear_##name(struct cfqg_stats *stats) \ { \ stats->flags &= ~(1 << CFQG_stats_##name); \ } \ static inline int cfqg_stats_##name(struct cfqg_stats *stats) \ { \ return (stats->flags & (1 << CFQG_stats_##name)) != 0; \ } \ CFQG_FLAG_FNS(waiting) CFQG_FLAG_FNS(idling) CFQG_FLAG_FNS(empty) #undef CFQG_FLAG_FNS /* This should be called with the queue_lock held. */
static void cfqg_stats_update_group_wait_time(struct cfqg_stats *stats) { unsigned long long now; if (!cfqg_stats_waiting(stats)) return; now = sched_clock(); if (time_after64(now, stats->start_group_wait_time)) blkg_stat_add(&stats->group_wait_time, now - stats->start_group_wait_time); cfqg_stats_clear_waiting(stats); }

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/* This should be called with the queue_lock held. */
static void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg, struct cfq_group *curr_cfqg) { struct cfqg_stats *stats = &cfqg->stats; if (cfqg_stats_waiting(stats)) return; if (cfqg == curr_cfqg) return; stats->start_group_wait_time = sched_clock(); cfqg_stats_mark_waiting(stats); }

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/* This should be called with the queue_lock held. */
static void cfqg_stats_end_empty_time(struct cfqg_stats *stats) { unsigned long long now; if (!cfqg_stats_empty(stats)) return; now = sched_clock(); if (time_after64(now, stats->start_empty_time)) blkg_stat_add(&stats->empty_time, now - stats->start_empty_time); cfqg_stats_clear_empty(stats); }

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static void cfqg_stats_update_dequeue(struct cfq_group *cfqg) { blkg_stat_add(&cfqg->stats.dequeue, 1); }

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static void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) { struct cfqg_stats *stats = &cfqg->stats; if (blkg_rwstat_total(&stats->queued)) return; /* * group is already marked empty. This can happen if cfqq got new * request in parent group and moved to this group while being added * to service tree. Just ignore the event and move on. */ if (cfqg_stats_empty(stats)) return; stats->start_empty_time = sched_clock(); cfqg_stats_mark_empty(stats); }

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static void cfqg_stats_update_idle_time(struct cfq_group *cfqg) { struct cfqg_stats *stats = &cfqg->stats; if (cfqg_stats_idling(stats)) { unsigned long long now = sched_clock(); if (time_after64(now, stats->start_idle_time)) blkg_stat_add(&stats->idle_time, now - stats->start_idle_time); cfqg_stats_clear_idling(stats); } }

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static void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) { struct cfqg_stats *stats = &cfqg->stats; BUG_ON(cfqg_stats_idling(stats)); stats->start_idle_time = sched_clock(); cfqg_stats_mark_idling(stats); }

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static void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) { struct cfqg_stats *stats = &cfqg->stats; blkg_stat_add(&stats->avg_queue_size_sum, blkg_rwstat_total(&stats->queued)); blkg_stat_add(&stats->avg_queue_size_samples, 1); cfqg_stats_update_group_wait_time(stats); }

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#else /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */
static inline void cfqg_stats_set_start_group_wait_time(struct cfq_group *cfqg, struct cfq_group *curr_cfqg) { }

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static inline void cfqg_stats_end_empty_time(struct cfqg_stats *stats) { }

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static inline void cfqg_stats_update_dequeue(struct cfq_group *cfqg) { }

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static inline void cfqg_stats_set_start_empty_time(struct cfq_group *cfqg) { }

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static inline void cfqg_stats_update_idle_time(struct cfq_group *cfqg) { }

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static inline void cfqg_stats_set_start_idle_time(struct cfq_group *cfqg) { }

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static inline void cfqg_stats_update_avg_queue_size(struct cfq_group *cfqg) { }

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#endif /* CONFIG_CFQ_GROUP_IOSCHED && CONFIG_DEBUG_BLK_CGROUP */ #ifdef CONFIG_CFQ_GROUP_IOSCHED
static inline struct cfq_group *pd_to_cfqg(struct blkg_policy_data *pd) { return pd ? container_of(pd, struct cfq_group, pd) : NULL; }

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static struct cfq_group_data *cpd_to_cfqgd(struct blkcg_policy_data *cpd) { return cpd ? container_of(cpd, struct cfq_group_data, cpd) : NULL; }

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static inline struct blkcg_gq *cfqg_to_blkg(struct cfq_group *cfqg) { return pd_to_blkg(&cfqg->pd); }

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static struct blkcg_policy blkcg_policy_cfq;
static inline struct cfq_group *blkg_to_cfqg(struct blkcg_gq *blkg) { return pd_to_cfqg(blkg_to_pd(blkg, &blkcg_policy_cfq)); }

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static struct cfq_group_data *blkcg_to_cfqgd(struct blkcg *blkcg) { return cpd_to_cfqgd(blkcg_to_cpd(blkcg, &blkcg_policy_cfq)); }

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static inline struct cfq_group *cfqg_parent(struct cfq_group *cfqg) { struct blkcg_gq *pblkg = cfqg_to_blkg(cfqg)->parent; return pblkg ? blkg_to_cfqg(pblkg) : NULL; }

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static inline bool cfqg_is_descendant(struct cfq_group *cfqg, struct cfq_group *ancestor) { return cgroup_is_descendant(cfqg_to_blkg(cfqg)->blkcg->css.cgroup, cfqg_to_blkg(ancestor)->blkcg->css.cgroup); }

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static inline void cfqg_get(struct cfq_group *cfqg) { return blkg_get(cfqg_to_blkg(cfqg)); }

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static inline void cfqg_put(struct cfq_group *cfqg) { return blkg_put(cfqg_to_blkg(cfqg)); }

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Tejun Heo21100.00%1100.00%
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#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) do { \ char __pbuf[128]; \ \ blkg_path(cfqg_to_blkg((cfqq)->cfqg), __pbuf, sizeof(__pbuf)); \ blk_add_trace_msg((cfqd)->queue, "cfq%d%c%c %s " fmt, (cfqq)->pid, \ cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ cfqq_type((cfqq)) == SYNC_NOIDLE_WORKLOAD ? 'N' : ' ',\ __pbuf, ##args); \ } while (0) #define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do { \ char __pbuf[128]; \ \ blkg_path(cfqg_to_blkg(cfqg), __pbuf, sizeof(__pbuf)); \ blk_add_trace_msg((cfqd)->queue, "%s " fmt, __pbuf, ##args); \ } while (0)
static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, struct cfq_group *curr_cfqg, unsigned int op) { blkg_rwstat_add(&cfqg->stats.queued, op, 1); cfqg_stats_end_empty_time(&cfqg->stats); cfqg_stats_set_start_group_wait_time(cfqg, curr_cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo4692.00%466.67%
Michael Christie36.00%116.67%
Christoph Hellwig12.00%116.67%
Total50100.00%6100.00%


static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg, uint64_t time, unsigned long unaccounted_time) { blkg_stat_add(&cfqg->stats.time, time); #ifdef CONFIG_DEBUG_BLK_CGROUP blkg_stat_add(&cfqg->stats.unaccounted_time, unaccounted_time); #endif }

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PersonTokensPropCommitsCommitProp
Tejun Heo4797.92%480.00%
Jeff Moyer12.08%120.00%
Total48100.00%5100.00%


static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, unsigned int op) { blkg_rwstat_add(&cfqg->stats.queued, op, -1); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo2787.10%466.67%
Michael Christie39.68%116.67%
Christoph Hellwig13.23%116.67%
Total31100.00%6100.00%


static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, unsigned int op) { blkg_rwstat_add(&cfqg->stats.merged, op, 1); }

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PersonTokensPropCommitsCommitProp
Tejun Heo2686.67%360.00%
Michael Christie310.00%120.00%
Christoph Hellwig13.33%120.00%
Total30100.00%5100.00%


static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, uint64_t start_time, uint64_t io_start_time, unsigned int op) { struct cfqg_stats *stats = &cfqg->stats; unsigned long long now = sched_clock(); if (time_after64(now, io_start_time)) blkg_rwstat_add(&stats->service_time, op, now - io_start_time); if (time_after64(io_start_time, start_time)) blkg_rwstat_add(&stats->wait_time, op, io_start_time - start_time); }

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PersonTokensPropCommitsCommitProp
Tejun Heo8093.02%360.00%
Michael Christie55.81%120.00%
Christoph Hellwig11.16%120.00%
Total86100.00%5100.00%

/* @stats = 0 */
static void cfqg_stats_reset(struct cfqg_stats *stats) { /* queued stats shouldn't be cleared */ blkg_rwstat_reset(&stats->merged); blkg_rwstat_reset(&stats->service_time); blkg_rwstat_reset(&stats->wait_time); blkg_stat_reset(&stats->time); #ifdef CONFIG_DEBUG_BLK_CGROUP blkg_stat_reset(&stats->unaccounted_time); blkg_stat_reset(&stats->avg_queue_size_sum); blkg_stat_reset(&stats->avg_queue_size_samples); blkg_stat_reset(&stats->dequeue); blkg_stat_reset(&stats->group_wait_time); blkg_stat_reset(&stats->idle_time); blkg_stat_reset(&stats->empty_time); #endif }

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PersonTokensPropCommitsCommitProp
Tejun Heo105100.00%2100.00%
Total105100.00%2100.00%

/* @to += @from */
static void cfqg_stats_add_aux(struct cfqg_stats *to, struct cfqg_stats *from) { /* queued stats shouldn't be cleared */ blkg_rwstat_add_aux(&to->merged, &from->merged); blkg_rwstat_add_aux(&to->service_time, &from->service_time); blkg_rwstat_add_aux(&to->wait_time, &from->wait_time); blkg_stat_add_aux(&from->time, &from->time); #ifdef CONFIG_DEBUG_BLK_CGROUP blkg_stat_add_aux(&to->unaccounted_time, &from->unaccounted_time); blkg_stat_add_aux(&to->avg_queue_size_sum, &from->avg_queue_size_sum); blkg_stat_add_aux(&to->avg_queue_size_samples, &from->avg_queue_size_samples); blkg_stat_add_aux(&to->dequeue, &from->dequeue); blkg_stat_add_aux(&to->group_wait_time, &from->group_wait_time); blkg_stat_add_aux(&to->idle_time, &from->idle_time); blkg_stat_add_aux(&to->empty_time, &from->empty_time); #endif }

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PersonTokensPropCommitsCommitProp
Tejun Heo165100.00%3100.00%
Total165100.00%3100.00%

/* * Transfer @cfqg's stats to its parent's aux counts so that the ancestors' * recursive stats can still account for the amount used by this cfqg after * it's gone. */
static void cfqg_stats_xfer_dead(struct cfq_group *cfqg) { struct cfq_group *parent = cfqg_parent(cfqg); lockdep_assert_held(cfqg_to_blkg(cfqg)->q->queue_lock); if (unlikely(!parent)) return; cfqg_stats_add_aux(&parent->stats, &cfqg->stats); cfqg_stats_reset(&cfqg->stats); }

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PersonTokensPropCommitsCommitProp
Tejun Heo63100.00%3100.00%
Total63100.00%3100.00%

#else /* CONFIG_CFQ_GROUP_IOSCHED */
static inline struct cfq_group *cfqg_parent(struct cfq_group *cfqg) { return NULL; }

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Tejun Heo17100.00%2100.00%
Total17100.00%2100.00%


static inline bool cfqg_is_descendant(struct cfq_group *cfqg, struct cfq_group *ancestor) { return true; }

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PersonTokensPropCommitsCommitProp
Jan Kara20100.00%1100.00%
Total20100.00%1100.00%


static inline void cfqg_get(struct cfq_group *cfqg) { }

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PersonTokensPropCommitsCommitProp
Tejun Heo11100.00%1100.00%
Total11100.00%1100.00%


static inline void cfqg_put(struct cfq_group *cfqg) { }

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PersonTokensPropCommitsCommitProp
Tejun Heo11100.00%1100.00%
Total11100.00%1100.00%

#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ blk_add_trace_msg((cfqd)->queue, "cfq%d%c%c " fmt, (cfqq)->pid, \ cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ cfqq_type((cfqq)) == SYNC_NOIDLE_WORKLOAD ? 'N' : ' ',\ ##args) #define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do {} while (0)
static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, struct cfq_group *curr_cfqg, unsigned int op) { }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo1890.00%250.00%
Michael Christie15.00%125.00%
Christoph Hellwig15.00%125.00%
Total20100.00%4100.00%


static inline void cfqg_stats_update_timeslice_used(struct cfq_group *cfqg, uint64_t time, unsigned long unaccounted_time) { }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo1794.44%266.67%
Jeff Moyer15.56%133.33%
Total18100.00%3100.00%


static inline void cfqg_stats_update_io_remove(struct cfq_group *cfqg, unsigned int op) { }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo1386.67%250.00%
Michael Christie16.67%125.00%
Christoph Hellwig16.67%125.00%
Total15100.00%4100.00%


static inline void cfqg_stats_update_io_merged(struct cfq_group *cfqg, unsigned int op) { }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo1386.67%250.00%
Christoph Hellwig16.67%125.00%
Michael Christie16.67%125.00%
Total15100.00%4100.00%


static inline void cfqg_stats_update_completion(struct cfq_group *cfqg, uint64_t start_time, uint64_t io_start_time, unsigned int op) { }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo1990.48%250.00%
Christoph Hellwig14.76%125.00%
Michael Christie14.76%125.00%
Total21100.00%4100.00%

#endif /* CONFIG_CFQ_GROUP_IOSCHED */ #define cfq_log(cfqd, fmt, args...) \ blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args) /* Traverses through cfq group service trees */ #define for_each_cfqg_st(cfqg, i, j, st) \ for (i = 0; i <= IDLE_WORKLOAD; i++) \ for (j = 0, st = i < IDLE_WORKLOAD ? &cfqg->service_trees[i][j]\ : &cfqg->service_tree_idle; \ (i < IDLE_WORKLOAD && j <= SYNC_WORKLOAD) || \ (i == IDLE_WORKLOAD && j == 0); \ j++, st = i < IDLE_WORKLOAD ? \ &cfqg->service_trees[i][j]: NULL) \ static inline bool cfq_io_thinktime_big(struct cfq_data *cfqd, struct cfq_ttime *ttime, bool group_idle) { u64 slice; if (!sample_valid(ttime->ttime_samples)) return false; if (group_idle) slice = cfqd->cfq_group_idle; else slice = cfqd->cfq_slice_idle; return ttime->ttime_mean > slice; }
static inline bool iops_mode(struct cfq_data *cfqd) { /* * If we are not idling on queues and it is a NCQ drive, parallel * execution of requests is on and measuring time is not possible * in most of the cases until and unless we drive shallower queue * depths and that becomes a performance bottleneck. In such cases * switch to start providing fairness in terms of number of IOs. */ if (!cfqd->cfq_slice_idle && cfqd->hw_tag) return true; else return false; }

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PersonTokensPropCommitsCommitProp
Vivek Goyal2064.52%133.33%
David Shaohua Li1032.26%133.33%
Corrado Zoccolo13.23%133.33%
Total31100.00%3100.00%


static inline enum wl_class_t cfqq_class(struct cfq_queue *cfqq) { if (cfq_class_idle(cfqq)) return IDLE_WORKLOAD; if (cfq_class_rt(cfqq)) return RT_WORKLOAD; return BE_WORKLOAD; }

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PersonTokensPropCommitsCommitProp
Corrado Zoccolo2466.67%133.33%
Vivek Goyal1233.33%266.67%
Total36100.00%3100.00%


static enum wl_type_t cfqq_type(struct cfq_queue *cfqq) { if (!cfq_cfqq_sync(cfqq)) return ASYNC_WORKLOAD; if (!cfq_cfqq_idle_window(cfqq)) return SYNC_NOIDLE_WORKLOAD; return SYNC_WORKLOAD; }

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PersonTokensPropCommitsCommitProp
Corrado Zoccolo37100.00%1100.00%
Total37100.00%1100.00%


static inline int cfq_group_busy_queues_wl(enum wl_class_t wl_class, struct cfq_data *cfqd, struct cfq_group *cfqg) { if (wl_class == IDLE_WORKLOAD) return cfqg->service_tree_idle.count; return cfqg->service_trees[wl_class][ASYNC_WORKLOAD].count + cfqg->service_trees[wl_class][SYNC_NOIDLE_WORKLOAD].count + cfqg->service_trees[wl_class][SYNC_WORKLOAD].count; }

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PersonTokensPropCommitsCommitProp
Corrado Zoccolo5374.65%240.00%
Vivek Goyal1825.35%360.00%
Total71100.00%5100.00%


static inline int cfqg_busy_async_queues(struct cfq_data *cfqd, struct cfq_group *cfqg) { return cfqg->service_trees[RT_WORKLOAD][ASYNC_WORKLOAD].count + cfqg->service_trees[BE_WORKLOAD][ASYNC_WORKLOAD].count; }

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PersonTokensPropCommitsCommitProp
Vivek Goyal42100.00%1100.00%
Total42100.00%1100.00%

static void cfq_dispatch_insert(struct request_queue *, struct request *); static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, struct bio *bio);
static inline struct cfq_io_cq *icq_to_cic(struct io_cq *icq) { /* cic->icq is the first member, %NULL will convert to %NULL */ return container_of(icq, struct cfq_io_cq, icq); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo26100.00%1100.00%
Total26100.00%1100.00%


static inline struct cfq_io_cq *cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc) { if (ioc) return icq_to_cic(ioc_lookup_icq(ioc, cfqd->queue)); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo39100.00%1100.00%
Total39100.00%1100.00%


static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_cq *cic, bool is_sync) { return cic->cfqq[is_sync]; }

Contributors

PersonTokensPropCommitsCommitProp
Vasily Tarasov1560.00%120.00%
Al Viro728.00%120.00%
Jens Axboe28.00%240.00%
Tejun Heo14.00%120.00%
Total25100.00%5100.00%


static inline void cic_set_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq, bool is_sync) { cic->cfqq[is_sync] = cfqq; }

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PersonTokensPropCommitsCommitProp
Vasily Tarasov2275.86%125.00%
Al Viro517.24%125.00%
Tejun Heo13.45%125.00%
Jens Axboe13.45%125.00%
Total29100.00%4100.00%


static inline struct cfq_data *cic_to_cfqd(struct cfq_io_cq *cic) { return cic->icq.q->elevator->elevator_data; }

Contributors

PersonTokensPropCommitsCommitProp
Konstantin Khlebnikov1664.00%133.33%
Tejun Heo936.00%266.67%
Total25100.00%3100.00%

/* * scheduler run of queue, if there are requests pending and no one in the * driver that will restart queueing */
static inline void cfq_schedule_dispatch(struct cfq_data *cfqd) { if (cfqd->busy_queues) { cfq_log(cfqd, "schedule dispatch"); kblockd_schedule_work(&cfqd->unplug_work); } }

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PersonTokensPropCommitsCommitProp
Andrew Morton2365.71%125.00%
Jens Axboe1234.29%375.00%
Total35100.00%4100.00%

/* * Scale schedule slice based on io priority. Use the sync time slice only * if a queue is marked sync and has sync io queued. A sync queue with async * io only, should not get full sync slice length. */
static inline u64 cfq_prio_slice(struct cfq_data *cfqd, bool sync, unsigned short prio) { u64 base_slice = cfqd->cfq_slice[sync]; u64 slice = div_u64(base_slice, CFQ_SLICE_SCALE); WARN_ON(prio >= IOPRIO_BE_NR); return base_slice + (slice * (4 - prio)); }

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PersonTokensPropCommitsCommitProp
Jens Axboe4677.97%375.00%
Jeff Moyer1322.03%125.00%
Total59100.00%4100.00%


static inline u64 cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) { return cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio); }

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PersonTokensPropCommitsCommitProp
Jens Axboe3196.88%266.67%
Jeff Moyer13.12%133.33%
Total32100.00%3100.00%

/** * cfqg_scale_charge - scale disk time charge according to cfqg weight * @charge: disk time being charged * @vfraction: vfraction of the cfqg, fixed point w/ CFQ_SERVICE_SHIFT * * Scale @charge according to @vfraction, which is in range (0, 1]. The * scaling is inversely proportional. * * scaled = charge / vfraction * * The result is also in fixed point w/ CFQ_SERVICE_SHIFT. */
static inline u64 cfqg_scale_charge(u64 charge, unsigned int vfraction) { u64 c = charge << CFQ_SERVICE_SHIFT; /* make it fixed point */ /* charge / vfraction */ c <<= CFQ_SERVICE_SHIFT; return div_u64(c, vfraction); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal1851.43%133.33%
Tejun Heo1440.00%133.33%
Jeff Moyer38.57%133.33%
Total35100.00%3100.00%


static inline u64 max_vdisktime(u64 min_vdisktime, u64 vdisktime) { s64 delta = (s64)(vdisktime - min_vdisktime); if (delta > 0) min_vdisktime = vdisktime; return min_vdisktime; }

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PersonTokensPropCommitsCommitProp
Vivek Goyal38100.00%1100.00%
Total38100.00%1100.00%


static void update_min_vdisktime(struct cfq_rb_root *st) { struct cfq_group *cfqg; if (st->left) { cfqg = rb_entry_cfqg(st->left); st->min_vdisktime = max_vdisktime(st->min_vdisktime, cfqg->vdisktime); } }

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PersonTokensPropCommitsCommitProp
Vivek Goyal4593.75%150.00%
Gui Jianfeng36.25%150.00%
Total48100.00%2100.00%

/* * get averaged number of queues of RT/BE priority. * average is updated, with a formula that gives more weight to higher numbers, * to quickly follows sudden increases and decrease slowly */
static inline unsigned cfq_group_get_avg_queues(struct cfq_data *cfqd, struct cfq_group *cfqg, bool rt) { unsigned min_q, max_q; unsigned mult = cfq_hist_divisor - 1; unsigned round = cfq_hist_divisor / 2; unsigned busy = cfq_group_busy_queues_wl(rt, cfqd, cfqg); min_q = min(cfqg->busy_queues_avg[rt], busy); max_q = max(cfqg->busy_queues_avg[rt], busy); cfqg->busy_queues_avg[rt] = (mult * max_q + min_q + round) / cfq_hist_divisor; return cfqg->busy_queues_avg[rt]; }

Contributors

PersonTokensPropCommitsCommitProp
Corrado Zoccolo8176.42%250.00%
Vivek Goyal1312.26%125.00%
Jens Axboe1211.32%125.00%
Total106100.00%4100.00%


static inline u64 cfq_group_slice(struct cfq_data *cfqd, struct cfq_group *cfqg) { return cfqd->cfq_target_latency * cfqg->vfraction >> CFQ_SERVICE_SHIFT; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal2071.43%120.00%
Jens Axboe414.29%240.00%
Tejun Heo310.71%120.00%
Jeff Moyer13.57%120.00%
Total28100.00%5100.00%


static inline u64 cfq_scaled_cfqq_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) { u64 slice = cfq_prio_to_slice(cfqd, cfqq); if (cfqd->cfq_latency) { /* * interested queues (we consider only the ones with the same * priority class in the cfq group) */ unsigned iq = cfq_group_get_avg_queues(cfqd, cfqq->cfqg, cfq_class_rt(cfqq)); u64 sync_slice = cfqd->cfq_slice[1]; u64 expect_latency = sync_slice * iq; u64 group_slice = cfq_group_slice(cfqd, cfqq->cfqg); if (expect_latency > group_slice) { u64 base_low_slice = 2 * cfqd->cfq_slice_idle; u64 low_slice; /* scale low_slice according to IO priority * and sync vs async */ low_slice = div64_u64(base_low_slice*slice, sync_slice); low_slice = min(slice, low_slice); /* the adapted slice value is scaled to fit all iqs * into the target latency */ slice = div64_u64(slice*group_slice, expect_latency); slice = max(slice, low_slice); } } return slice; }

Contributors

PersonTokensPropCommitsCommitProp
Corrado Zoccolo6644.90%116.67%
Jeff Moyer3121.09%116.67%
Jens Axboe2416.33%116.67%
Vivek Goyal2214.97%233.33%
David Shaohua Li42.72%116.67%
Total147100.00%6100.00%


static inline void cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq) { u64 slice = cfq_scaled_cfqq_slice(cfqd, cfqq); u64 now = ktime_get_ns(); cfqq->slice_start = now; cfqq->slice_end = now + slice; cfqq->allocated_slice = slice; cfq_log_cfqq(cfqd, cfqq, "set_slice=%llu", cfqq->slice_end - now); }

Contributors

PersonTokensPropCommitsCommitProp
David Shaohua Li2435.29%112.50%
Jens Axboe1522.06%225.00%
Vivek Goyal1217.65%337.50%
Jeff Moyer1116.18%112.50%
Corrado Zoccolo68.82%112.50%
Total68100.00%8100.00%

/* * We need to wrap this check in cfq_cfqq_slice_new(), since ->slice_end * isn't valid until the first request from the dispatch is activated * and the slice time set. */
static inline bool cfq_slice_used(struct cfq_queue *cfqq) { if (cfq_cfqq_slice_new(cfqq)) return false; if (ktime_get_ns() < cfqq->slice_end) return false; return true; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe3183.78%250.00%
Jeff Moyer38.11%125.00%
David Shaohua Li38.11%125.00%
Total37100.00%4100.00%

/* * Lifted from AS - choose which of rq1 and rq2 that is best served now. * We choose the request that is closest to the head right now. Distance * behind the head is penalized and only allowed to a certain extent. */
static struct request * cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2, sector_t last) { sector_t s1, s2, d1 = 0, d2 = 0; unsigned long back_max; #define CFQ_RQ1_WRAP 0x01 /* request 1 wraps */ #define CFQ_RQ2_WRAP 0x02 /* request 2 wraps */ unsigned wrap = 0; /* bit mask: requests behind the disk head? */ if (rq1 == NULL || rq1 == rq2) return rq2; if (rq2 == NULL) return rq1; if (rq_is_sync(rq1) != rq_is_sync(rq2)) return rq_is_sync(rq1) ? rq1 : rq2; if ((rq1->cmd_flags ^ rq2->cmd_flags) & REQ_PRIO) return rq1->cmd_flags & REQ_PRIO ? rq1 : rq2; s1 = blk_rq_pos(rq1); s2 = blk_rq_pos(rq2); /* * by definition, 1KiB is 2 sectors */ back_max = cfqd->cfq_back_max * 2; /* * Strict one way elevator _except_ in the case where we allow * short backward seeks which are biased as twice the cost of a * similar forward seek. */ if (s1 >= last) d1 = s1 - last; else if (s1 + back_max >= last) d1 = (last - s1) * cfqd->cfq_back_penalty; else wrap |= CFQ_RQ1_WRAP; if (s2 >= last) d2 = s2 - last; else if (s2 + back_max >= last) d2 = (last - s2) * cfqd->cfq_back_penalty; else wrap |= CFQ_RQ2_WRAP; /* Found required data */ /* * By doing switch() on the bit mask "wrap" we avoid having to * check two variables for all permutations: --> faster! */ switch (wrap) { case 0: /* common case for CFQ: rq1 and rq2 not wrapped */ if (d1 < d2) return rq1; else if (d2 < d1) return rq2; else { if (s1 >= s2) return rq1; else return rq2; } case CFQ_RQ2_WRAP: return rq1; case CFQ_RQ1_WRAP: return rq2; case (CFQ_RQ1_WRAP|CFQ_RQ2_WRAP): /* both rqs wrapped */ default: /* * Since both rqs are wrapped, * start with the one that's further behind head * (--> only *one* back seek required), * since back seek takes more time than forward. */ if (s1 <= s2) return rq1; else return rq2; } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe20465.81%650.00%
Andreas Mohr5517.74%18.33%
Andrew Morton3611.61%18.33%
Tejun Heo61.94%18.33%
Namhyung Kim41.29%18.33%
Corrado Zoccolo30.97%18.33%
Christoph Hellwig20.65%18.33%
Total310100.00%12100.00%

/* * The below is leftmost cache rbtree addon */
static struct cfq_queue *cfq_rb_first(struct cfq_rb_root *root) { /* Service tree is empty */ if (!root->count) return NULL; if (!root->left) root->left = rb_first(&root->rb); if (root->left) return rb_entry(root->left, struct cfq_queue, rb_node); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe5483.08%266.67%
Vivek Goyal1116.92%133.33%
Total65100.00%3100.00%


static struct cfq_group *cfq_rb_first_group(struct cfq_rb_root *root) { if (!root->left) root->left = rb_first(&root->rb); if (root->left) return rb_entry_cfqg(root->left); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal49100.00%1100.00%
Total49100.00%1100.00%


static void rb_erase_init(struct rb_node *n, struct rb_root *root) { rb_erase(n, root); RB_CLEAR_NODE(n); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe28100.00%1100.00%
Total28100.00%1100.00%


static void cfq_rb_erase(struct rb_node *n, struct cfq_rb_root *root) { if (root->left == n) root->left = NULL; rb_erase_init(n, &root->rb); --root->count; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4088.89%266.67%
Corrado Zoccolo511.11%133.33%
Total45100.00%3100.00%

/* * would be nice to take fifo expire time into account as well */
static struct request * cfq_find_next_rq(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct request *last) { struct rb_node *rbnext = rb_next(&last->rb_node); struct rb_node *rbprev = rb_prev(&last->rb_node); struct request *next = NULL, *prev = NULL; BUG_ON(RB_EMPTY_NODE(&last->rb_node)); if (rbprev) prev = rb_entry_rq(rbprev); if (rbnext) next = rb_entry_rq(rbnext); else { rbnext = rb_first(&cfqq->sort_list); if (rbnext && rbnext != &last->rb_node) next = rb_entry_rq(rbnext); } return cfq_choose_req(cfqd, next, prev, blk_rq_pos(last)); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe6949.29%466.67%
Vivek Goyal4330.71%116.67%
Andrew Morton2820.00%116.67%
Total140100.00%6100.00%


static u64 cfq_slice_offset(struct cfq_data *cfqd, struct cfq_queue *cfqq) { /* * just an approximation, should be ok. */ return (cfqq->cfqg->nr_cfqq - 1) * (cfq_prio_slice(cfqd, 1, 0) - cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio)); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal5298.11%150.00%
Jeff Moyer11.89%150.00%
Total53100.00%2100.00%


static inline s64 cfqg_key(struct cfq_rb_root *st, struct cfq_group *cfqg) { return cfqg->vdisktime - st->min_vdisktime; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal26100.00%1100.00%
Total26100.00%1100.00%


static void __cfq_group_service_tree_add(struct cfq_rb_root *st, struct cfq_group *cfqg) { struct rb_node **node = &st->rb.rb_node; struct rb_node *parent = NULL; struct cfq_group *__cfqg; s64 key = cfqg_key(st, cfqg); int left = 1; while (*node != NULL) { parent = *node; __cfqg = rb_entry_cfqg(parent); if (key < cfqg_key(st, __cfqg)) node = &parent->rb_left; else { node = &parent->rb_right; left = 0; } } if (left) st->left = &cfqg->rb_node; rb_link_node(&cfqg->rb_node, parent, node); rb_insert_color(&cfqg->rb_node, &st->rb); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal147100.00%1100.00%
Total147100.00%1100.00%

/* * This has to be called only on activation of cfqg */
static void cfq_update_group_weight(struct cfq_group *cfqg) { if (cfqg->new_weight) { cfqg->weight = cfqg->new_weight; cfqg->new_weight = 0; } }

Contributors

PersonTokensPropCommitsCommitProp
Justin TerAvest2781.82%125.00%
Tejun Heo39.09%125.00%
Vivek Goyal26.06%125.00%
Toshiaki Makita13.03%125.00%
Total33100.00%4100.00%


static void cfq_update_group_leaf_weight(struct cfq_group *cfqg) { BUG_ON(!RB_EMPTY_NODE(&cfqg->rb_node)); if (cfqg->new_leaf_weight) { cfqg->leaf_weight = cfqg->new_leaf_weight; cfqg->new_leaf_weight = 0; } }

Contributors

PersonTokensPropCommitsCommitProp
Toshiaki Makita2248.89%133.33%
Tejun Heo2248.89%133.33%
Justin TerAvest12.22%133.33%
Total45100.00%3100.00%


static void cfq_group_service_tree_add(struct cfq_rb_root *st, struct cfq_group *cfqg) { unsigned int vfr = 1 << CFQ_SERVICE_SHIFT; /* start with 1 */ struct cfq_group *pos = cfqg; struct cfq_group *parent; bool propagate; /* add to the service tree */ BUG_ON(!RB_EMPTY_NODE(&cfqg->rb_node)); /* * Update leaf_weight. We cannot update weight at this point * because cfqg might already have been activated and is * contributing its current weight to the parent's child_weight. */ cfq_update_group_leaf_weight(cfqg); __cfq_group_service_tree_add(st, cfqg); /* * Activate @cfqg and calculate the portion of vfraction @cfqg is * entitled to. vfraction is calculated by walking the tree * towards the root calculating the fraction it has at each level. * The compounded ratio is how much vfraction @cfqg owns. * * Start with the proportion tasks in this cfqg has against active * children cfqgs - its leaf_weight against children_weight. */ propagate = !pos->nr_active++; pos->children_weight += pos->leaf_weight; vfr = vfr * pos->leaf_weight / pos->children_weight; /* * Compound ->weight walking up the tree. Both activation and * vfraction calculation are done in the same loop. Propagation * stops once an already activated node is met. vfraction * calculation should always continue to the root. */ while ((parent = cfqg_parent(pos))) { if (propagate) { cfq_update_group_weight(pos); propagate = !parent->nr_active++; parent->children_weight += pos->weight; } vfr = vfr * pos->weight / parent->children_weight; pos = parent; } cfqg->vfraction = max_t(unsigned, vfr, 1); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo11368.48%342.86%
Justin TerAvest4024.24%114.29%
Toshiaki Makita74.24%228.57%
Vivek Goyal53.03%114.29%
Total165100.00%7100.00%


static inline u64 cfq_get_cfqg_vdisktime_delay(struct cfq_data *cfqd) { if (!iops_mode(cfqd)) return CFQ_SLICE_MODE_GROUP_DELAY; else return CFQ_IOPS_MODE_GROUP_DELAY; }

Contributors

PersonTokensPropCommitsCommitProp
Hou Tao27100.00%1100.00%
Total27100.00%1100.00%


static void cfq_group_notify_queue_add(struct cfq_data *cfqd, struct cfq_group *cfqg) { struct cfq_rb_root *st = &cfqd->grp_service_tree; struct cfq_group *__cfqg; struct rb_node *n; cfqg->nr_cfqq++; if (!RB_EMPTY_NODE(&cfqg->rb_node)) return; /* * Currently put the group at the end. Later implement something * so that groups get lesser vtime based on their weights, so that * if group does not loose all if it was not continuously backlogged. */ n = rb_last(&st->rb); if (n) { __cfqg = rb_entry_cfqg(n); cfqg->vdisktime = __cfqg->vdisktime + cfq_get_cfqg_vdisktime_delay(cfqd); } else cfqg->vdisktime = st->min_vdisktime; cfq_group_service_tree_add(st, cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal7267.92%111.11%
Jens Axboe1312.26%222.22%
Justin TerAvest76.60%111.11%
Gui Jianfeng65.66%111.11%
Hou Tao43.77%111.11%
Andrew Morton21.89%111.11%
Corrado Zoccolo10.94%111.11%
Lucas De Marchi10.94%111.11%
Total106100.00%9100.00%


static void cfq_group_service_tree_del(struct cfq_rb_root *st, struct cfq_group *cfqg) { struct cfq_group *pos = cfqg; bool propagate; /* * Undo activation from cfq_group_service_tree_add(). Deactivate * @cfqg and propagate deactivation upwards. */ propagate = !--pos->nr_active; pos->children_weight -= pos->leaf_weight; while (propagate) { struct cfq_group *parent = cfqg_parent(pos); /* @pos has 0 nr_active at this point */ WARN_ON_ONCE(pos->children_weight); pos->vfraction = 0; if (!parent) break; propagate = !--parent->nr_active; parent->children_weight -= pos->weight; pos = parent; } /* remove from the service tree */ if (!RB_EMPTY_NODE(&cfqg->rb_node)) cfq_rb_erase(&cfqg->rb_node, st); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo7965.29%350.00%
Justin TerAvest3730.58%116.67%
Vivek Goyal43.31%116.67%
Jens Axboe10.83%116.67%
Total121100.00%6100.00%


static void cfq_group_notify_queue_del(struct cfq_data *cfqd, struct cfq_group *cfqg) { struct cfq_rb_root *st = &cfqd->grp_service_tree; BUG_ON(cfqg->nr_cfqq < 1); cfqg->nr_cfqq--; /* If there are other cfq queues under this group, don't delete it */ if (cfqg->nr_cfqq) return; cfq_log_cfqg(cfqd, cfqg, "del_from_rr group"); cfq_group_service_tree_del(st, cfqg); cfqg->saved_wl_slice = 0; cfqg_stats_update_dequeue(cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal5370.67%640.00%
Jens Axboe1520.00%640.00%
Justin TerAvest45.33%16.67%
Tejun Heo34.00%213.33%
Total75100.00%15100.00%


static inline u64 cfq_cfqq_slice_usage(struct cfq_queue *cfqq, u64 *unaccounted_time) { u64 slice_used; u64 now = ktime_get_ns(); /* * Queue got expired before even a single request completed or * got expired immediately after first request completion. */ if (!cfqq->slice_start || cfqq->slice_start == now) { /* * Also charge the seek time incurred to the group, otherwise * if there are mutiple queues in the group, each can dispatch * a single request on seeky media and cause lots of seek time * and group will never know it. */ slice_used = max_t(u64, (now - cfqq->dispatch_start), jiffies_to_nsecs(1)); } else { slice_used = now - cfqq->slice_start; if (slice_used > cfqq->allocated_slice) { *unaccounted_time = slice_used - cfqq->allocated_slice; slice_used = cfqq->allocated_slice; } if (cfqq->slice_start > cfqq->dispatch_start) *unaccounted_time += cfqq->slice_start - cfqq->dispatch_start; } return slice_used; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal7158.20%240.00%
Justin TerAvest3427.87%120.00%
Jeff Moyer1411.48%120.00%
Jan Kara32.46%120.00%
Total122100.00%5100.00%


static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg, struct cfq_queue *cfqq) { struct cfq_rb_root *st = &cfqd->grp_service_tree; u64 used_sl, charge, unaccounted_sl = 0; int nr_sync = cfqg->nr_cfqq - cfqg_busy_async_queues(cfqd, cfqg) - cfqg->service_tree_idle.count; unsigned int vfr; u64 now = ktime_get_ns(); BUG_ON(nr_sync < 0); used_sl = charge = cfq_cfqq_slice_usage(cfqq, &unaccounted_sl); if (iops_mode(cfqd)) charge = cfqq->slice_dispatch; else if (!cfq_cfqq_sync(cfqq) && !nr_sync) charge = cfqq->allocated_slice; /* * Can't update vdisktime while on service tree and cfqg->vfraction * is valid only while on it. Cache vfr, leave the service tree, * update vdisktime and go back on. The re-addition to the tree * will also update the weights as necessary. */ vfr = cfqg->vfraction; cfq_group_service_tree_del(st, cfqg); cfqg->vdisktime += cfqg_scale_charge(charge, vfr); cfq_group_service_tree_add(st, cfqg); /* This group is being expired. Save the context */ if (cfqd->workload_expires > now) { cfqg->saved_wl_slice = cfqd->workload_expires - now; cfqg->saved_wl_type = cfqd->serving_wl_type; cfqg->saved_wl_class = cfqd->serving_wl_class; } else cfqg->saved_wl_slice = 0; cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime, st->min_vdisktime); cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%llu disp=%llu charge=%llu iops=%u sect=%lu", used_sl, cfqq->slice_dispatch, charge, iops_mode(cfqd), cfqq->nr_sectors); cfqg_stats_update_timeslice_used(cfqg, used_sl, unaccounted_sl); cfqg_stats_set_start_empty_time(cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal20981.96%743.75%
Tejun Heo197.45%425.00%
Justin TerAvest135.10%212.50%
Jeff Moyer114.31%16.25%
Divyesh Shah20.78%16.25%
Jens Axboe10.39%16.25%
Total255100.00%16100.00%

/** * cfq_init_cfqg_base - initialize base part of a cfq_group * @cfqg: cfq_group to initialize * * Initialize the base part which is used whether %CONFIG_CFQ_GROUP_IOSCHED * is enabled or not. */
static void cfq_init_cfqg_base(struct cfq_group *cfqg) { struct cfq_rb_root *st; int i, j; for_each_cfqg_st(cfqg, i, j, st) *st = CFQ_RB_ROOT; RB_CLEAR_NODE(&cfqg->rb_node); cfqg->ttime.last_end_request = ktime_get_ns(); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo5196.23%150.00%
Jeff Moyer23.77%150.00%
Total53100.00%2100.00%

#ifdef CONFIG_CFQ_GROUP_IOSCHED static int __cfq_set_weight(struct cgroup_subsys_state *css, u64 val, bool on_dfl, bool reset_dev, bool is_leaf_weight);
static void cfqg_stats_exit(struct cfqg_stats *stats) { blkg_rwstat_exit(&stats->merged); blkg_rwstat_exit(&stats->service_time); blkg_rwstat_exit(&stats->wait_time); blkg_rwstat_exit(&stats->queued); blkg_stat_exit(&stats->time); #ifdef CONFIG_DEBUG_BLK_CGROUP blkg_stat_exit(&stats->unaccounted_time); blkg_stat_exit(&stats->avg_queue_size_sum); blkg_stat_exit(&stats->avg_queue_size_samples); blkg_stat_exit(&stats->dequeue); blkg_stat_exit(&stats->group_wait_time); blkg_stat_exit(&stats->idle_time); blkg_stat_exit(&stats->empty_time); #endif }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo11098.21%150.00%
Peter Zijlstra21.79%150.00%
Total112100.00%2100.00%


static int cfqg_stats_init(struct cfqg_stats *stats, gfp_t gfp) { if (blkg_rwstat_init(&stats->merged, gfp) || blkg_rwstat_init(&stats->service_time, gfp) || blkg_rwstat_init(&stats->wait_time, gfp) || blkg_rwstat_init(&stats->queued, gfp) || blkg_stat_init(&stats->time, gfp)) goto err; #ifdef CONFIG_DEBUG_BLK_CGROUP if (blkg_stat_init(&stats->unaccounted_time, gfp) || blkg_stat_init(&stats->avg_queue_size_sum, gfp) || blkg_stat_init(&stats->avg_queue_size_samples, gfp) || blkg_stat_init(&stats->dequeue, gfp) || blkg_stat_init(&stats->group_wait_time, gfp) || blkg_stat_init(&stats->idle_time, gfp) || blkg_stat_init(&stats->empty_time, gfp)) goto err; #endif return 0; err: cfqg_stats_exit(stats); return -ENOMEM; }

Contributors

PersonTokensPropCommitsCommitProp
Peter Zijlstra9860.12%150.00%
Tejun Heo6539.88%150.00%
Total163100.00%2100.00%


static struct blkcg_policy_data *cfq_cpd_alloc(gfp_t gfp) { struct cfq_group_data *cgd; cgd = kzalloc(sizeof(*cgd), gfp); if (!cgd) return NULL; return &cgd->cpd; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo43100.00%2100.00%
Total43100.00%2100.00%


static void cfq_cpd_init(struct blkcg_policy_data *cpd) { struct cfq_group_data *cgd = cpd_to_cfqgd(cpd); unsigned int weight = cgroup_subsys_on_dfl(io_cgrp_subsys) ? CGROUP_WEIGHT_DFL : CFQ_WEIGHT_LEGACY_DFL; if (cpd_to_blkcg(cpd) == &blkcg_root) weight *= 2; cgd->weight = weight; cgd->leaf_weight = weight; }

Contributors

PersonTokensPropCommitsCommitProp
Arianna Avanzini3761.67%125.00%
Tejun Heo2338.33%375.00%
Total60100.00%4100.00%


static void cfq_cpd_free(struct blkcg_policy_data *cpd) { kfree(cpd_to_cfqgd(cpd)); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo19100.00%1100.00%
Total19100.00%1100.00%


static void cfq_cpd_bind(struct blkcg_policy_data *cpd) { struct blkcg *blkcg = cpd_to_blkcg(cpd); bool on_dfl = cgroup_subsys_on_dfl(io_cgrp_subsys); unsigned int weight = on_dfl ? CGROUP_WEIGHT_DFL : CFQ_WEIGHT_LEGACY_DFL; if (blkcg == &blkcg_root) weight *= 2; WARN_ON_ONCE(__cfq_set_weight(&blkcg->css, weight, on_dfl, true, false)); WARN_ON_ONCE(__cfq_set_weight(&blkcg->css, weight, on_dfl, true, true)); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo88100.00%2100.00%
Total88100.00%2100.00%


static struct blkg_policy_data *cfq_pd_alloc(gfp_t gfp, int node) { struct cfq_group *cfqg; cfqg = kzalloc_node(sizeof(*cfqg), gfp, node); if (!cfqg) return NULL; cfq_init_cfqg_base(cfqg); if (cfqg_stats_init(&cfqg->stats, gfp)) { kfree(cfqg); return NULL; } return &cfqg->pd; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo75100.00%3100.00%
Total75100.00%3100.00%


static void cfq_pd_init(struct blkg_policy_data *pd) { struct cfq_group *cfqg = pd_to_cfqg(pd); struct cfq_group_data *cgd = blkcg_to_cfqgd(pd->blkg->blkcg); cfqg->weight = cgd->weight; cfqg->leaf_weight = cgd->leaf_weight; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo2549.02%666.67%
Arianna Avanzini1631.37%111.11%
Vivek Goyal1019.61%222.22%
Total51100.00%9100.00%


static void cfq_pd_offline(struct blkg_policy_data *pd) { struct cfq_group *cfqg = pd_to_cfqg(pd); int i; for (i = 0; i < IOPRIO_BE_NR; i++) { if (cfqg->async_cfqq[0][i]) cfq_put_queue(cfqg->async_cfqq[0][i]); if (cfqg->async_cfqq[1][i]) cfq_put_queue(cfqg->async_cfqq[1][i]); } if (cfqg->async_idle_cfqq) cfq_put_queue(cfqg->async_idle_cfqq); /* * @blkg is going offline and will be ignored by * blkg_[rw]stat_recursive_sum(). Transfer stats to the parent so * that they don't get lost. If IOs complete after this point, the * stats for them will be lost. Oh well... */ cfqg_stats_xfer_dead(cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo108100.00%4100.00%
Total108100.00%4100.00%


static void cfq_pd_free(struct blkg_policy_data *pd) { struct cfq_group *cfqg = pd_to_cfqg(pd); cfqg_stats_exit(&cfqg->stats); return kfree(cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo35100.00%2100.00%
Total35100.00%2100.00%


static void cfq_pd_reset_stats(struct blkg_policy_data *pd) { struct cfq_group *cfqg = pd_to_cfqg(pd); cfqg_stats_reset(&cfqg->stats); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo29100.00%2100.00%
Total29100.00%2100.00%


static struct cfq_group *cfq_lookup_cfqg(struct cfq_data *cfqd, struct blkcg *blkcg) { struct blkcg_gq *blkg; blkg = blkg_lookup(blkcg, cfqd->queue); if (likely(blkg)) return blkg_to_cfqg(blkg); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo50100.00%3100.00%
Total50100.00%3100.00%


static void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) { cfqq->cfqg = cfqg; /* cfqq reference on cfqg */ cfqg_get(cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo28100.00%1100.00%
Total28100.00%1100.00%


static u64 cfqg_prfill_weight_device(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct cfq_group *cfqg = pd_to_cfqg(pd); if (!cfqg->dev_weight) return 0; return __blkg_prfill_u64(sf, pd, cfqg->dev_weight); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo51100.00%3100.00%
Total51100.00%3100.00%


static int cfqg_print_weight_device(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_weight_device, &blkcg_policy_cfq, 0, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo40100.00%6100.00%
Total40100.00%6100.00%


static u64 cfqg_prfill_leaf_weight_device(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct cfq_group *cfqg = pd_to_cfqg(pd); if (!cfqg->dev_leaf_weight) return 0; return __blkg_prfill_u64(sf, pd, cfqg->dev_leaf_weight); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo51100.00%2100.00%
Total51100.00%2100.00%


static int cfqg_print_leaf_weight_device(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_leaf_weight_device, &blkcg_policy_cfq, 0, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo40100.00%3100.00%
Total40100.00%3100.00%


static int cfq_print_weight(struct seq_file *sf, void *v) { struct blkcg *blkcg = css_to_blkcg(seq_css(sf)); struct cfq_group_data *cgd = blkcg_to_cfqgd(blkcg); unsigned int val = 0; if (cgd) val = cgd->weight; seq_printf(sf, "%u\n", val); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe2740.91%120.00%
Tejun Heo2334.85%360.00%
Arianna Avanzini1624.24%120.00%
Total66100.00%5100.00%


static int cfq_print_leaf_weight(struct seq_file *sf, void *v) { struct blkcg *blkcg = css_to_blkcg(seq_css(sf)); struct cfq_group_data *cgd = blkcg_to_cfqgd(blkcg); unsigned int val = 0; if (cgd) val = cgd->leaf_weight; seq_printf(sf, "%u\n", val); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe2740.91%120.00%
Tejun Heo2334.85%360.00%
Arianna Avanzini1624.24%120.00%
Total66100.00%5100.00%


static ssize_t __cfqg_set_weight_device(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off, bool on_dfl, bool is_leaf_weight) { unsigned int min = on_dfl ? CGROUP_WEIGHT_MIN : CFQ_WEIGHT_LEGACY_MIN; unsigned int max = on_dfl ? CGROUP_WEIGHT_MAX : CFQ_WEIGHT_LEGACY_MAX; struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct cfq_group *cfqg; struct cfq_group_data *cfqgd; int ret; u64 v; ret = blkg_conf_prep(blkcg, &blkcg_policy_cfq, buf, &ctx); if (ret) return ret; if (sscanf(ctx.body, "%llu", &v) == 1) { /* require "default" on dfl */ ret = -ERANGE; if (!v && on_dfl) goto out_finish; } else if (!strcmp(strim(ctx.body), "default")) { v = 0; } else { ret = -EINVAL; goto out_finish; } cfqg = blkg_to_cfqg(ctx.blkg); cfqgd = blkcg_to_cfqgd(blkcg); ret = -ERANGE; if (!v || (v >= min && v <= max)) { if (!is_leaf_weight) { cfqg->dev_weight = v; cfqg->new_weight = v ?: cfqgd->weight; } else { cfqg->dev_leaf_weight = v; cfqg->new_leaf_weight = v ?: cfqgd->leaf_weight; } ret = 0; } out_finish: blkg_conf_finish(&ctx); return ret ?: nbytes; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo25092.94%1285.71%
Arianna Avanzini165.95%17.14%
Jens Axboe31.12%17.14%
Total269100.00%14100.00%


static ssize_t cfqg_set_weight_device(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { return __cfqg_set_weight_device(of, buf, nbytes, off, false, false); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo37100.00%4100.00%
Total37100.00%4100.00%


static ssize_t cfqg_set_leaf_weight_device(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { return __cfqg_set_weight_device(of, buf, nbytes, off, false, true); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo37100.00%3100.00%
Total37100.00%3100.00%


static int __cfq_set_weight(struct cgroup_subsys_state *css, u64 val, bool on_dfl, bool reset_dev, bool is_leaf_weight) { unsigned int min = on_dfl ? CGROUP_WEIGHT_MIN : CFQ_WEIGHT_LEGACY_MIN; unsigned int max = on_dfl ? CGROUP_WEIGHT_MAX : CFQ_WEIGHT_LEGACY_MAX; struct blkcg *blkcg = css_to_blkcg(css); struct blkcg_gq *blkg; struct cfq_group_data *cfqgd; int ret = 0; if (val < min || val > max) return -ERANGE; spin_lock_irq(&blkcg->lock); cfqgd = blkcg_to_cfqgd(blkcg); if (!cfqgd) { ret = -EINVAL; goto out; } if (!is_leaf_weight) cfqgd->weight = val; else cfqgd->leaf_weight = val; hlist_for_each_entry(blkg, &blkcg->blkg_list, blkcg_node) { struct cfq_group *cfqg = blkg_to_cfqg(blkg); if (!cfqg) continue; if (!is_leaf_weight) { if (reset_dev) cfqg->dev_weight = 0; if (!cfqg->dev_weight) cfqg->new_weight = cfqgd->weight; } else { if (reset_dev) cfqg->dev_leaf_weight = 0; if (!cfqg->dev_leaf_weight) cfqg->new_leaf_weight = cfqgd->leaf_weight; } } out: spin_unlock_irq(&blkcg->lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo18681.22%675.00%
Jens Axboe2310.04%112.50%
Arianna Avanzini208.73%112.50%
Total229100.00%8100.00%


static int cfq_set_weight(struct cgroup_subsys_state *css, struct cftype *cft, u64 val) { return __cfq_set_weight(css, val, false, false, false); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo33100.00%3100.00%
Total33100.00%3100.00%


static int cfq_set_leaf_weight(struct cgroup_subsys_state *css, struct cftype *cft, u64 val) { return __cfq_set_weight(css, val, false, false, true); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo33100.00%3100.00%
Total33100.00%3100.00%


static int cfqg_print_stat(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_stat, &blkcg_policy_cfq, seq_cft(sf)->private, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo45100.00%4100.00%
Total45100.00%4100.00%


static int cfqg_print_rwstat(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat, &blkcg_policy_cfq, seq_cft(sf)->private, true); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo45100.00%4100.00%
Total45100.00%4100.00%


static u64 cfqg_prfill_stat_recursive(struct seq_file *sf, struct blkg_policy_data *pd, int off) { u64 sum = blkg_stat_recursive_sum(pd_to_blkg(pd), &blkcg_policy_cfq, off); return __blkg_prfill_u64(sf, pd, sum); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo45100.00%3100.00%
Total45100.00%3100.00%


static u64 cfqg_prfill_rwstat_recursive(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct blkg_rwstat sum = blkg_rwstat_recursive_sum(pd_to_blkg(pd), &blkcg_policy_cfq, off); return __blkg_prfill_rwstat(sf, pd, &sum); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo47100.00%4100.00%
Total47100.00%4100.00%


static int cfqg_print_stat_recursive(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_stat_recursive, &blkcg_policy_cfq, seq_cft(sf)->private, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo45100.00%5100.00%
Total45100.00%5100.00%


static int cfqg_print_rwstat_recursive(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_rwstat_recursive, &blkcg_policy_cfq, seq_cft(sf)->private, true); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo45100.00%5100.00%
Total45100.00%5100.00%


static u64 cfqg_prfill_sectors(struct seq_file *sf, struct blkg_policy_data *pd, int off) { u64 sum = blkg_rwstat_total(&pd->blkg->stat_bytes); return __blkg_prfill_u64(sf, pd, sum >> 9); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo44100.00%1100.00%
Total44100.00%1100.00%


static int cfqg_print_stat_sectors(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_sectors, &blkcg_policy_cfq, 0, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo40100.00%1100.00%
Total40100.00%1100.00%


static u64 cfqg_prfill_sectors_recursive(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct blkg_rwstat tmp = blkg_rwstat_recursive_sum(pd->blkg, NULL, offsetof(struct blkcg_gq, stat_bytes)); u64 sum = atomic64_read(&tmp.aux_cnt[BLKG_RWSTAT_READ]) + atomic64_read(&tmp.aux_cnt[BLKG_RWSTAT_WRITE]); return __blkg_prfill_u64(sf, pd, sum >> 9); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo77100.00%1100.00%
Total77100.00%1100.00%


static int cfqg_print_stat_sectors_recursive(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_sectors_recursive, &blkcg_policy_cfq, 0, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo40100.00%1100.00%
Total40100.00%1100.00%

#ifdef CONFIG_DEBUG_BLK_CGROUP
static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct cfq_group *cfqg = pd_to_cfqg(pd); u64 samples = blkg_stat_read(&cfqg->stats.avg_queue_size_samples); u64 v = 0; if (samples) { v = blkg_stat_read(&cfqg->stats.avg_queue_size_sum); v = div64_u64(v, samples); } __blkg_prfill_u64(sf, pd, v); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo8396.51%375.00%
Anatol Pomozov33.49%125.00%
Total86100.00%4100.00%

/* print avg_queue_size */
static int cfqg_print_avg_queue_size(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), cfqg_prfill_avg_queue_size, &blkcg_policy_cfq, 0, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo40100.00%5100.00%
Total40100.00%5100.00%

#endif /* CONFIG_DEBUG_BLK_CGROUP */ static struct cftype cfq_blkcg_legacy_files[] = { /* on root, weight is mapped to leaf_weight */ { .name = "weight_device", .flags = CFTYPE_ONLY_ON_ROOT, .seq_show = cfqg_print_leaf_weight_device, .write = cfqg_set_leaf_weight_device, }, { .name = "weight", .flags = CFTYPE_ONLY_ON_ROOT, .seq_show = cfq_print_leaf_weight, .write_u64 = cfq_set_leaf_weight, }, /* no such mapping necessary for !roots */ { .name = "weight_device", .flags = CFTYPE_NOT_ON_ROOT, .seq_show = cfqg_print_weight_device, .write = cfqg_set_weight_device, }, { .name = "weight", .flags = CFTYPE_NOT_ON_ROOT, .seq_show = cfq_print_weight, .write_u64 = cfq_set_weight, }, { .name = "leaf_weight_device", .seq_show = cfqg_print_leaf_weight_device, .write = cfqg_set_leaf_weight_device, }, { .name = "leaf_weight", .seq_show = cfq_print_leaf_weight, .write_u64 = cfq_set_leaf_weight, }, /* statistics, covers only the tasks in the cfqg */ { .name = "time", .private = offsetof(struct cfq_group, stats.time), .seq_show = cfqg_print_stat, }, { .name = "sectors", .seq_show = cfqg_print_stat_sectors, }, { .name = "io_service_bytes", .private = (unsigned long)&blkcg_policy_cfq, .seq_show = blkg_print_stat_bytes, }, { .name = "io_serviced", .private = (unsigned long)&blkcg_policy_cfq, .seq_show = blkg_print_stat_ios, }, { .name = "io_service_time", .private = offsetof(struct cfq_group, stats.service_time), .seq_show = cfqg_print_rwstat, }, { .name = "io_wait_time", .private = offsetof(struct cfq_group, stats.wait_time), .seq_show = cfqg_print_rwstat, }, { .name = "io_merged", .private = offsetof(struct cfq_group, stats.merged), .seq_show = cfqg_print_rwstat, }, { .name = "io_queued", .private = offsetof(struct cfq_group, stats.queued), .seq_show = cfqg_print_rwstat, }, /* the same statictics which cover the cfqg and its descendants */ { .name = "time_recursive", .private = offsetof(struct cfq_group, stats.time), .seq_show = cfqg_print_stat_recursive, }, { .name = "sectors_recursive", .seq_show = cfqg_print_stat_sectors_recursive, }, { .name = "io_service_bytes_recursive", .private = (unsigned long)&blkcg_policy_cfq, .seq_show = blkg_print_stat_bytes_recursive, }, { .name = "io_serviced_recursive", .private = (unsigned long)&blkcg_policy_cfq, .seq_show = blkg_print_stat_ios_recursive, }, { .name = "io_service_time_recursive", .private = offsetof(struct cfq_group, stats.service_time), .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_wait_time_recursive", .private = offsetof(struct cfq_group, stats.wait_time), .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_merged_recursive", .private = offsetof(struct cfq_group, stats.merged), .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_queued_recursive", .private = offsetof(struct cfq_group, stats.queued), .seq_show = cfqg_print_rwstat_recursive, }, #ifdef CONFIG_DEBUG_BLK_CGROUP { .name = "avg_queue_size", .seq_show = cfqg_print_avg_queue_size, }, { .name = "group_wait_time", .private = offsetof(struct cfq_group, stats.group_wait_time), .seq_show = cfqg_print_stat, }, { .name = "idle_time", .private = offsetof(struct cfq_group, stats.idle_time), .seq_show = cfqg_print_stat, }, { .name = "empty_time", .private = offsetof(struct cfq_group, stats.empty_time), .seq_show = cfqg_print_stat, }, { .name = "dequeue", .private = offsetof(struct cfq_group, stats.dequeue), .seq_show = cfqg_print_stat, }, { .name = "unaccounted_time", .private = offsetof(struct cfq_group, stats.unaccounted_time), .seq_show = cfqg_print_stat, }, #endif /* CONFIG_DEBUG_BLK_CGROUP */ { } /* terminate */ };
static int cfq_print_weight_on_dfl(struct seq_file *sf, void *v) { struct blkcg *blkcg = css_to_blkcg(seq_css(sf)); struct cfq_group_data *cgd = blkcg_to_cfqgd(blkcg); seq_printf(sf, "default %u\n", cgd->weight); blkcg_print_blkgs(sf, blkcg, cfqg_prfill_weight_device, &blkcg_policy_cfq, 0, false); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo68100.00%1100.00%
Total68100.00%1100.00%


static ssize_t cfq_set_weight_on_dfl(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { char *endp; int ret; u64 v; buf = strim(buf); /* "WEIGHT" or "default WEIGHT" sets the default weight */ v = simple_strtoull(buf, &endp, 0); if (*endp == '\0' || sscanf(buf, "default %llu", &v) == 1) { ret = __cfq_set_weight(of_css(of), v, true, false, false); return ret ?: nbytes; } /* "MAJ:MIN WEIGHT" */ return __cfqg_set_weight_device(of, buf, nbytes, off, true, false); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo113100.00%2100.00%
Total113100.00%2100.00%

static struct cftype cfq_blkcg_files[] = { { .name = "weight", .flags = CFTYPE_NOT_ON_ROOT, .seq_show = cfq_print_weight_on_dfl, .write = cfq_set_weight_on_dfl, }, { } /* terminate */ }; #else /* GROUP_IOSCHED */
static struct cfq_group *cfq_lookup_cfqg(struct cfq_data *cfqd, struct blkcg *blkcg) { return cfqd->root_group; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal1773.91%125.00%
Tejun Heo626.09%375.00%
Total23100.00%4100.00%


static inline void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) { cfqq->cfqg = cfqg; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal23100.00%1100.00%
Total23100.00%1100.00%

#endif /* GROUP_IOSCHED */ /* * The cfqd->service_trees holds all pending cfq_queue's that have * requests waiting to be processed. It is sorted in the order that * we will service the queues. */
static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq, bool add_front) { struct rb_node **p, *parent; struct cfq_queue *__cfqq; u64 rb_key; struct cfq_rb_root *st; int left; int new_cfqq = 1; u64 now = ktime_get_ns(); st = st_for(cfqq->cfqg, cfqq_class(cfqq), cfqq_type(cfqq)); if (cfq_class_idle(cfqq)) { rb_key = CFQ_IDLE_DELAY; parent = rb_last(&st->rb); if (parent && parent != &cfqq->rb_node) { __cfqq = rb_entry(parent, struct cfq_queue, rb_node); rb_key += __cfqq->rb_key; } else rb_key += now; } else if (!add_front) { /* * Get our rb key offset. Subtract any residual slice * value carried from last service. A negative resid * count indicates slice overrun, and this should position * the next service time further away in the tree. */ rb_key = cfq_slice_offset(cfqd, cfqq) + now; rb_key -= cfqq->slice_resid; cfqq->slice_resid = 0; } else { rb_key = -NSEC_PER_SEC; __cfqq = cfq_rb_first(st); rb_key += __cfqq ? __cfqq->rb_key : now; } if (!RB_EMPTY_NODE(&cfqq->rb_node)) { new_cfqq = 0; /* * same position, nothing more to do */ if (rb_key == cfqq->rb_key && cfqq->service_tree == st) return; cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree); cfqq->service_tree = NULL; } left = 1; parent = NULL; cfqq->service_tree = st; p = &st->rb.rb_node; while (*p) { parent = *p; __cfqq = rb_entry(parent, struct cfq_queue, rb_node); /* * sort by key, that represents service time. */ if (rb_key < __cfqq->rb_key) p = &parent->rb_left; else { p = &parent->rb_right; left = 0; } } if (left) st->left = &cfqq->rb_node; cfqq->rb_key = rb_key; rb_link_node(&cfqq->rb_node, parent, p); rb_insert_color(&cfqq->rb_node, &st->rb); st->count++; if (add_front || !new_cfqq) return; cfq_group_notify_queue_add(cfqd, cfqq->cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe26368.49%1145.83%
Corrado Zoccolo6216.15%416.67%
Vivek Goyal4511.72%625.00%
Jeff Moyer123.12%14.17%
Andrew Morton10.26%14.17%
Justin TerAvest10.26%14.17%
Total384100.00%24100.00%


static struct cfq_queue * cfq_prio_tree_lookup(struct cfq_data *cfqd, struct rb_root *root, sector_t sector, struct rb_node **ret_parent, struct rb_node ***rb_link) { struct rb_node **p, *parent; struct cfq_queue *cfqq = NULL; parent = NULL; p = &root->rb_node; while (*p) { struct rb_node **n; parent = *p; cfqq = rb_entry(parent, struct cfq_queue, p_node); /* * Sort strictly based on sector. Smallest to the left, * largest to the right. */ if (sector > blk_rq_pos(cfqq->next_rq)) n = &(*p)->rb_right; else if (sector < blk_rq_pos(cfqq->next_rq)) n = &(*p)->rb_left; else break; p = n; cfqq = NULL; } *ret_parent = parent; if (rb_link) *rb_link = p; return cfqq; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe15092.59%777.78%
Divyesh Shah63.70%111.11%
Tejun Heo63.70%111.11%
Total162100.00%9100.00%


static void cfq_prio_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq) { struct rb_node **p, *parent; struct cfq_queue *__cfqq; if (cfqq->p_root) { rb_erase(&cfqq->p_node, cfqq->p_root); cfqq->p_root = NULL; } if (cfq_class_idle(cfqq)) return; if (!cfqq->next_rq) return; cfqq->p_root = &cfqd->prio_trees[cfqq->org_ioprio]; __cfqq = cfq_prio_tree_lookup(cfqd, cfqq->p_root, blk_rq_pos(cfqq->next_rq), &parent, &p); if (!__cfqq) { rb_link_node(&cfqq->p_node, parent, p); rb_insert_color(&cfqq->p_node, cfqq->p_root); } else cfqq->p_root = NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe13289.19%770.00%
Andrew Morton96.08%110.00%
Divyesh Shah42.70%110.00%
Tejun Heo32.03%110.00%
Total148100.00%10100.00%

/* * Update cfqq's position in the service tree. */
static void cfq_resort_rr_list(struct cfq_data *cfqd, struct cfq_queue *cfqq) { /* * Resorting requires the cfqq to be on the RR list already. */ if (cfq_cfqq_on_rr(cfqq)) { cfq_service_tree_add(cfqd, cfqq, 0); cfq_prio_tree_add(cfqd, cfqq); } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe3890.48%480.00%
Andrew Morton49.52%120.00%
Total42100.00%5100.00%

/* * add to busy list of queues for service, trying to be fair in ordering * the pending list according to last request service */
static void cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) { cfq_log_cfqq(cfqd, cfqq, "add_to_rr"); BUG_ON(cfq_cfqq_on_rr(cfqq)); cfq_mark_cfqq_on_rr(cfqq); cfqd->busy_queues++; if (cfq_cfqq_sync(cfqq)) cfqd->busy_sync_queues++; cfq_resort_rr_list(cfqd, cfqq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4369.35%571.43%
David Shaohua Li1219.35%114.29%
Andrew Morton711.29%114.29%
Total62100.00%7100.00%

/* * Called when the cfqq no longer has requests pending, remove it from * the service tree. */
static void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq) { cfq_log_cfqq(cfqd, cfqq, "del_from_rr"); BUG_ON(!cfq_cfqq_on_rr(cfqq)); cfq_clear_cfqq_on_rr(cfqq); if (!RB_EMPTY_NODE(&cfqq->rb_node)) { cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree); cfqq->service_tree = NULL; } if (cfqq->p_root) { rb_erase(&cfqq->p_node, cfqq->p_root); cfqq->p_root = NULL; } cfq_group_notify_queue_del(cfqd, cfqq->cfqg); BUG_ON(!cfqd->busy_queues); cfqd->busy_queues--; if (cfq_cfqq_sync(cfqq)) cfqd->busy_sync_queues--; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe9673.85%337.50%
David Shaohua Li129.23%112.50%
Corrado Zoccolo96.92%112.50%
Vivek Goyal86.15%112.50%
Andrew Morton43.08%112.50%
Justin TerAvest10.77%112.50%
Total130100.00%8100.00%

/* * rb tree support functions */
static void cfq_del_rq_rb(struct request *rq) { struct cfq_queue *cfqq = RQ_CFQQ(rq); const int sync = rq_is_sync(rq); BUG_ON(!cfqq->queued[sync]); cfqq->queued[sync]--; elv_rb_del(&cfqq->sort_list, rq); if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list)) { /* * Queue will be deleted from service tree when we actually * expire it later. Right now just remove it from prio tree * as it is empty. */ if (cfqq->p_root) { rb_erase(&cfqq->p_node, cfqq->p_root); cfqq->p_root = NULL; } } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe7976.70%150.00%
Vivek Goyal2423.30%150.00%
Total103100.00%2100.00%


static void cfq_add_rq_rb(struct request *rq) { struct cfq_queue *cfqq = RQ_CFQQ(rq); struct cfq_data *cfqd = cfqq->cfqd; struct request *prev; cfqq->queued[rq_is_sync(rq)]++; elv_rb_add(&cfqq->sort_list, rq); if (!cfq_cfqq_on_rr(cfqq)) cfq_add_cfqq_rr(cfqd, cfqq); /* * check if this request is a better next-serve candidate */ prev = cfqq->next_rq; cfqq->next_rq = cfq_choose_req(cfqd, cfqq->next_rq, rq, cfqd->last_position); /* * adjust priority tree position, if ->next_rq changes */ if (prev != cfqq->next_rq) cfq_prio_tree_add(cfqd, cfqq); BUG_ON(!cfqq->next_rq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe10990.08%880.00%
Andrew Morton86.61%110.00%
Corrado Zoccolo43.31%110.00%
Total121100.00%10100.00%


static void cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq) { elv_rb_del(&cfqq->sort_list, rq); cfqq->queued[rq_is_sync(rq)]--; cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags); cfq_add_rq_rb(rq); cfqg_stats_update_io_add(RQ_CFQG(rq), cfqq->cfqd->serving_group, rq->cmd_flags); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe2433.33%545.45%
Andrew Morton1825.00%19.09%
Divyesh Shah1318.06%19.09%
Tejun Heo912.50%327.27%
Vivek Goyal811.11%19.09%
Total72100.00%11100.00%


static struct request * cfq_find_rq_fmerge(struct cfq_data *cfqd, struct bio *bio) { struct task_struct *tsk = current; struct cfq_io_cq *cic; struct cfq_queue *cfqq; cic = cfq_cic_lookup(cfqd, tsk->io_context); if (!cic) return NULL; cfqq = cic_to_cfqq(cic, op_is_sync(bio->bi_opf)); if (cfqq) return elv_rb_find(&cfqq->sort_list, bio_end_sector(bio)); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe3235.96%550.00%
Andrew Morton2528.09%110.00%
Vasily Tarasov2426.97%110.00%
Kent Overstreet44.49%110.00%
Christoph Hellwig33.37%110.00%
Tejun Heo11.12%110.00%
Total89100.00%10100.00%


static void cfq_activate_request(struct request_queue *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; cfqd->rq_in_driver++; cfq_log_cfqq(cfqd, RQ_CFQQ(rq), "activate rq, drv=%d", cfqd->rq_in_driver); cfqd->last_position = blk_rq_pos(rq) + blk_rq_sectors(rq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4775.81%770.00%
Andrew Morton711.29%110.00%
Tejun Heo69.68%110.00%
Corrado Zoccolo23.23%110.00%
Total62100.00%10100.00%


static void cfq_deactivate_request(struct request_queue *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; WARN_ON(!cfqd->rq_in_driver); cfqd->rq_in_driver--; cfq_log_cfqq(cfqd, RQ_CFQQ(rq), "deactivate rq, drv=%d", cfqd->rq_in_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4783.93%675.00%
Andrew Morton712.50%112.50%
Corrado Zoccolo23.57%112.50%
Total56100.00%8100.00%


static void cfq_remove_request(struct request *rq) { struct cfq_queue *cfqq = RQ_CFQQ(rq); if (cfqq->next_rq == rq) cfqq->next_rq = cfq_find_next_rq(cfqq->cfqd, cfqq, rq); list_del_init(&rq->queuelist); cfq_del_rq_rb(rq); cfqq->cfqd->rq_queued--; cfqg_stats_update_io_remove(RQ_CFQG(rq), rq->cmd_flags); if (rq->cmd_flags & REQ_PRIO) { WARN_ON(!cfqq->prio_pending); cfqq->prio_pending--; } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe6060.61%436.36%
Andrew Morton1717.17%19.09%
Aaron Carroll77.07%19.09%
Vivek Goyal44.04%19.09%
Tejun Heo44.04%218.18%
Divyesh Shah44.04%19.09%
Christoph Hellwig33.03%19.09%
Total99100.00%11100.00%


static enum elv_merge cfq_merge(struct request_queue *q, struct request **req, struct bio *bio) { struct cfq_data *cfqd = q->elevator->elevator_data; struct request *__rq; __rq = cfq_find_rq_fmerge(cfqd, bio); if (__rq && elv_bio_merge_ok(__rq, bio)) { *req = __rq; return ELEVATOR_FRONT_MERGE; } return ELEVATOR_NO_MERGE; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe5475.00%770.00%
Andrew Morton1520.83%110.00%
Christoph Hellwig22.78%110.00%
Tahsin Erdogan11.39%110.00%
Total72100.00%10100.00%


static void cfq_merged_request(struct request_queue *q, struct request *req, enum elv_merge type) { if (type == ELEVATOR_FRONT_MERGE) { struct cfq_queue *cfqq = RQ_CFQQ(req); cfq_reposition_rq_rb(cfqq, req); } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4191.11%571.43%
Christoph Hellwig24.44%114.29%
Andrew Morton24.44%114.29%
Total45100.00%7100.00%


static void cfq_bio_merged(struct request_queue *q, struct request *req, struct bio *bio) { cfqg_stats_update_io_merged(RQ_CFQG(req), bio->bi_opf); }

Contributors

PersonTokensPropCommitsCommitProp
Divyesh Shah2575.76%120.00%
Vivek Goyal412.12%120.00%
Tejun Heo39.09%240.00%
Jens Axboe13.03%120.00%
Total33100.00%5100.00%


static void cfq_merged_requests(struct request_queue *q, struct request *rq, struct request *next) { struct cfq_queue *cfqq = RQ_CFQQ(rq); struct cfq_data *cfqd = q->elevator->elevator_data; /* * reposition in fifo if next is older than rq */ if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist) && next->fifo_time < rq->fifo_time && cfqq == RQ_CFQQ(next)) { list_move(&rq->queuelist, &next->queuelist); rq->fifo_time = next->fifo_time; } if (cfqq->next_rq == next) cfqq->next_rq = rq; cfq_remove_request(next); cfqg_stats_update_io_merged(RQ_CFQG(rq), next->cmd_flags); cfqq = RQ_CFQQ(next); /* * all requests of this queue are merged to other queues, delete it * from the service tree. If it's the active_queue, * cfq_dispatch_requests() will choose to expire it or do idle */ if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list) && cfqq != cfqd->active_queue) cfq_del_cfqq_rr(cfqd, cfqq); }

Contributors

PersonTokensPropCommitsCommitProp
David Shaohua Li4727.98%16.67%
Jens Axboe4325.60%533.33%
Andrew Morton2514.88%16.67%
Corrado Zoccolo2414.29%16.67%
Jan Kara95.36%16.67%
Shaohua Li74.17%16.67%
Tejun Heo42.38%213.33%
Divyesh Shah42.38%16.67%
Vivek Goyal42.38%16.67%
Jeff Moyer10.60%16.67%
Total168100.00%15100.00%


static int cfq_allow_bio_merge(struct request_queue *q, struct request *rq, struct bio *bio) { struct cfq_data *cfqd = q->elevator->elevator_data; bool is_sync = op_is_sync(bio->bi_opf); struct cfq_io_cq *cic; struct cfq_queue *cfqq; /* * Disallow merge of a sync bio into an async request. */ if (is_sync && !rq_is_sync(rq)) return false; /* * Lookup the cfqq that this bio will be queued with and allow * merge only if rq is queued there. */ cic = cfq_cic_lookup(cfqd, current->io_context); if (!cic) return false; cfqq = cic_to_cfqq(cic, is_sync); return cfqq == RQ_CFQQ(rq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe7168.93%654.55%
Vasily Tarasov1716.50%19.09%
Christoph Hellwig1211.65%19.09%
Tejun Heo21.94%218.18%
Tahsin Erdogan10.97%19.09%
Total103100.00%11100.00%


static int cfq_allow_rq_merge(struct request_queue *q, struct request *rq, struct request *next) { return RQ_CFQQ(rq) == RQ_CFQQ(next); }

Contributors

PersonTokensPropCommitsCommitProp
Tahsin Erdogan32100.00%1100.00%
Total32100.00%1100.00%


static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq) { hrtimer_try_to_cancel(&cfqd->idle_slice_timer); cfqg_stats_update_idle_time(cfqq->cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Divyesh Shah2887.50%125.00%
Tejun Heo39.38%250.00%
Jan Kara13.12%125.00%
Total32100.00%4100.00%


static void __cfq_set_active_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (cfqq) { cfq_log_cfqq(cfqd, cfqq, "set_active wl_class:%d wl_type:%d", cfqd->serving_wl_class, cfqd->serving_wl_type); cfqg_stats_update_avg_queue_size(cfqq->cfqg); cfqq->slice_start = 0; cfqq->dispatch_start = ktime_get_ns(); cfqq->allocated_slice = 0; cfqq->slice_end = 0; cfqq->slice_dispatch = 0; cfqq->nr_sectors = 0; cfq_clear_cfqq_wait_request(cfqq); cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_must_alloc_slice(cfqq); cfq_clear_cfqq_fifo_expire(cfqq); cfq_mark_cfqq_slice_new(cfqq); cfq_del_timer(cfqd, cfqq); } cfqd->active_queue = cfqq; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe5142.15%736.84%
Vivek Goyal2621.49%526.32%
Justin TerAvest2016.53%15.26%
Andrew Morton129.92%15.26%
Divyesh Shah75.79%210.53%
Tejun Heo32.48%210.53%
Jeff Moyer21.65%15.26%
Total121100.00%19100.00%

/* * current cfqq expired its slice (or was too idle), select new one */
static void __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, bool timed_out) { cfq_log_cfqq(cfqd, cfqq, "slice expired t=%d", timed_out); if (cfq_cfqq_wait_request(cfqq)) cfq_del_timer(cfqd, cfqq); cfq_clear_cfqq_wait_request(cfqq); cfq_clear_cfqq_wait_busy(cfqq); /* * If this cfqq is shared between multiple processes, check to * make sure that those processes are still issuing I/Os within * the mean seek distance. If not, it may be time to break the * queues apart again. */ if (cfq_cfqq_coop(cfqq) && CFQQ_SEEKY(cfqq)) cfq_mark_cfqq_split_coop(cfqq); /* * store what was left of this slice, if the queue idled/timed out */ if (timed_out) { if (cfq_cfqq_slice_new(cfqq)) cfqq->slice_resid = cfq_scaled_cfqq_slice(cfqd, cfqq); else cfqq->slice_resid = cfqq->slice_end - ktime_get_ns(); cfq_log_cfqq(cfqd, cfqq, "resid=%lld", cfqq->slice_resid); } cfq_group_served(cfqd, cfqq->cfqg, cfqq); if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY_ROOT(&cfqq->sort_list)) cfq_del_cfqq_rr(cfqd, cfqq); cfq_resort_rr_list(cfqd, cfqq); if (cfqq == cfqd->active_queue) cfqd->active_queue = NULL; if (cfqd->active_cic) { put_io_context(cfqd->active_cic->icq.ioc); cfqd->active_cic = NULL; } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe12160.20%947.37%
Vivek Goyal3919.40%421.05%
David Shaohua Li3316.42%210.53%
Divyesh Shah31.49%15.26%
Tejun Heo21.00%15.26%
Jeff Moyer21.00%15.26%
Jan Kara10.50%15.26%
Total201100.00%19100.00%


static inline void cfq_slice_expired(struct cfq_data *cfqd, bool timed_out) { struct cfq_queue *cfqq = cfqd->active_queue; if (cfqq) __cfq_slice_expired(cfqd, cfqq, timed_out); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe37100.00%4100.00%
Total37100.00%4100.00%

/* * Get next queue for service. Unless we have a queue preemption, * we'll simply select the first cfqq in the service tree. */
static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd) { struct cfq_rb_root *st = st_for(cfqd->serving_group, cfqd->serving_wl_class, cfqd->serving_wl_type); if (!cfqd->rq_queued) return NULL; /* There is nothing to dispatch */ if (!st) return NULL; if (RB_EMPTY_ROOT(&st->rb)) return NULL; return cfq_rb_first(st); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal2940.85%535.71%
Jens Axboe2738.03%642.86%
Corrado Zoccolo1318.31%214.29%
Andrew Morton22.82%17.14%
Total71100.00%14100.00%


static struct cfq_queue *cfq_get_next_queue_forced(struct cfq_data *cfqd) { struct cfq_group *cfqg; struct cfq_queue *cfqq; int i, j; struct cfq_rb_root *st; if (!cfqd->rq_queued) return NULL; cfqg = cfq_get_next_cfqg(cfqd); if (!cfqg) return NULL; for_each_cfqg_st(cfqg, i, j, st) { cfqq = cfq_rb_first(st); if (cfqq) return cfqq; } return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal8193.10%266.67%
SF Markus Elfring66.90%133.33%
Total87100.00%3100.00%

/* * Get and set a new active queue for service. */
static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (!cfqq) cfqq = cfq_get_next_queue(cfqd); __cfq_set_active_queue(cfqd, cfqq); return cfqq; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe40100.00%1100.00%
Total40100.00%1100.00%


static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd, struct request *rq) { if (blk_rq_pos(rq) >= cfqd->last_position) return blk_rq_pos(rq) - cfqd->last_position; else return cfqd->last_position - blk_rq_pos(rq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4081.63%150.00%
Tejun Heo918.37%150.00%
Total49100.00%2100.00%


static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct request *rq) { return cfq_dist_from_last(cfqd, rq) <= CFQQ_CLOSE_THR; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe2681.25%133.33%
Jeff Moyer515.62%133.33%
David Shaohua Li13.12%133.33%
Total32100.00%3100.00%


static struct cfq_queue *cfqq_close(struct cfq_data *cfqd, struct cfq_queue *cur_cfqq) { struct rb_root *root = &cfqd->prio_trees[cur_cfqq->org_ioprio]; struct rb_node *parent, *node; struct cfq_queue *__cfqq; sector_t sector = cfqd->last_position; if (RB_EMPTY_ROOT(root)) return NULL; /* * First, if we find a request starting at the end of the last * request, choose it. */ __cfqq = cfq_prio_tree_lookup(cfqd, root, sector, &parent, NULL); if (__cfqq) return __cfqq; /* * If the exact sector wasn't found, the parent of the NULL leaf * will contain the closest sector. */ __cfqq = rb_entry(parent, struct cfq_queue, p_node); if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq)) return __cfqq; if (blk_rq_pos(__cfqq->next_rq) < sector) node = rb_next(&__cfqq->p_node); else node = rb_prev(&__cfqq->p_node); if (!node) return NULL; __cfqq = rb_entry(node, struct cfq_queue, p_node); if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq)) return __cfqq; return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe18096.26%571.43%
Jeff Moyer42.14%114.29%
Tejun Heo31.60%114.29%
Total187100.00%7100.00%

/* * cfqd - obvious * cur_cfqq - passed in so that we don't decide that the current queue is * closely cooperating with itself. * * So, basically we're assuming that that cur_cfqq has dispatched at least * one request, and that cfqd->last_position reflects a position on the disk * associated with the I/O issued by cur_cfqq. I'm not sure this is a valid * assumption. */
static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd, struct cfq_queue *cur_cfqq) { struct cfq_queue *cfqq; if (cfq_class_idle(cur_cfqq)) return NULL; if (!cfq_cfqq_sync(cur_cfqq)) return NULL; if (CFQQ_SEEKY(cur_cfqq)) return NULL; /* * Don't search priority tree if it's the only queue in the group. */ if (cur_cfqq->cfqg->nr_cfqq == 1) return NULL; /* * We should notice if some of the queues are cooperating, eg * working closely on the same area of the disk. In that case, * we can group them together and don't waste time idling. */ cfqq = cfqq_close(cfqd, cur_cfqq); if (!cfqq) return NULL; /* If new queue belongs to different cfq_group, don't choose it */ if (cur_cfqq->cfqg != cfqq->cfqg) return NULL; /* * It only makes sense to merge sync queues. */ if (!cfq_cfqq_sync(cfqq)) return NULL; if (CFQQ_SEEKY(cfqq)) return NULL; /* * Do not merge queues of different priority classes */ if (cfq_class_rt(cfqq) != cfq_class_rt(cur_cfqq)) return NULL; return cfqq; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4431.21%545.45%
Jeff Moyer4330.50%218.18%
Corrado Zoccolo1611.35%19.09%
Gui Jianfeng149.93%19.09%
Vivek Goyal149.93%19.09%
Divyesh Shah107.09%19.09%
Total141100.00%11100.00%

/* * Determine whether we should enforce idle window for this queue. */
static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq) { enum wl_class_t wl_class = cfqq_class(cfqq); struct cfq_rb_root *st = cfqq->service_tree; BUG_ON(!st); BUG_ON(!st->count); if (!cfqd->cfq_slice_idle) return false; /* We never do for idle class queues. */ if (wl_class == IDLE_WORKLOAD) return false; /* We do for queues that were marked with idle window flag. */ if (cfq_cfqq_idle_window(cfqq) && !(blk_queue_nonrot(cfqd->queue) && cfqd->hw_tag)) return true; /* * Otherwise, we do only if they are the last ones * in their service tree. */ if (st->count == 1 && cfq_cfqq_sync(cfqq) && !cfq_io_thinktime_big(cfqd, &st->ttime, false)) return true; cfq_log_cfqq(cfqd, cfqq, "Not idling. st->count:%d", st->count); return false; }

Contributors

PersonTokensPropCommitsCommitProp
Corrado Zoccolo5438.85%216.67%
Vivek Goyal3726.62%541.67%
David Shaohua Li2820.14%325.00%
Divyesh Shah1812.95%18.33%
Jens Axboe21.44%18.33%
Total139100.00%12100.00%


static void cfq_arm_slice_timer(struct cfq_data *cfqd) { struct cfq_queue *cfqq = cfqd->active_queue; struct cfq_rb_root *st = cfqq->service_tree; struct cfq_io_cq *cic; u64 sl, group_idle = 0; u64 now = ktime_get_ns(); /* * SSD device without seek penalty, disable idling. But only do so * for devices that support queuing, otherwise we still have a problem * with sync vs async workloads. */ if (blk_queue_nonrot(cfqd->queue) && cfqd->hw_tag) return; WARN_ON(!RB_EMPTY_ROOT(&cfqq->sort_list)); WARN_ON(cfq_cfqq_slice_new(cfqq)); /* * idle is disabled, either manually or by past process history */ if (!cfq_should_idle(cfqd, cfqq)) { /* no queue idling. Check for group idling */ if (cfqd->cfq_group_idle) group_idle = cfqd->cfq_group_idle; else return; } /* * still active requests from this queue, don't idle */ if (cfqq->dispatched) return; /* * task has exited, don't wait */ cic = cfqd->active_cic; if (!cic || !atomic_read(&cic->icq.ioc->active_ref)) return; /* * If our average think time is larger than the remaining time * slice, then don't idle. This avoids overrunning the allotted * time slice. */ if (sample_valid(cic->ttime.ttime_samples) && (cfqq->slice_end - now < cic->ttime.ttime_mean)) { cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%llu", cic->ttime.ttime_mean); return; } /* * There are other queues in the group or this is the only group and * it has too big thinktime, don't do group idle. */ if (group_idle && (cfqq->cfqg->nr_cfqq > 1 || cfq_io_thinktime_big(cfqd, &st->ttime, true))) return; cfq_mark_cfqq_wait_request(cfqq); if (group_idle) sl = cfqd->cfq_group_idle; else sl = cfqd->cfq_slice_idle; hrtimer_start(&cfqd->idle_slice_timer, ns_to_ktime(sl), HRTIMER_MODE_REL); cfqg_stats_set_start_idle_time(cfqq->cfqg); cfq_log_cfqq(cfqd, cfqq, "arm_idle: %llu group_idle: %d", sl, group_idle ? 1 : 0); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe10939.35%1242.86%
Vivek Goyal5018.05%13.57%
Jan Kara3010.83%27.14%
Corrado Zoccolo2910.47%310.71%
Divyesh Shah186.50%27.14%
Andrew Morton145.05%13.57%
Jeff Moyer103.61%13.57%
Tejun Heo72.53%414.29%
David Shaohua Li62.17%13.57%
Nikanth Karthikesan41.44%13.57%
Total277100.00%28100.00%

/* * Move request from internal lists to the request queue dispatch list. */
static void cfq_dispatch_insert(struct request_queue *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_queue *cfqq = RQ_CFQQ(rq); cfq_log_cfqq(cfqd, cfqq, "dispatch_insert"); cfqq->next_rq = cfq_find_next_rq(cfqd, cfqq, rq); cfq_remove_request(rq); cfqq->dispatched++; (RQ_CFQG(rq))->dispatched++; elv_dispatch_sort(q, rq); cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++; cfqq->nr_sectors += blk_rq_sectors(rq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe5955.66%1066.67%
Vivek Goyal1917.92%213.33%
Jeff Moyer1312.26%16.67%
Andrew Morton109.43%16.67%
Corrado Zoccolo54.72%16.67%
Total106100.00%15100.00%

/* * return expired entry, or NULL to just start from scratch in rbtree */
static struct request *cfq_check_fifo(struct cfq_queue *cfqq) { struct request *rq = NULL; if (cfq_cfqq_fifo_expire(cfqq)) return NULL; cfq_mark_cfqq_fifo_expire(cfqq); if (list_empty(&cfqq->fifo)) return NULL; rq = rq_entry_fifo(cfqq->fifo.next); if (ktime_get_ns() < rq->fifo_time) rq = NULL; return rq; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe6586.67%1178.57%
Andrew Morton56.67%17.14%
Jeff Moyer34.00%17.14%
Jan Kara22.67%17.14%
Total75100.00%14100.00%


static inline int cfq_prio_to_maxrq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { const int base_rq = cfqd->cfq_slice_async_rq; WARN_ON(cfqq->ioprio >= IOPRIO_BE_NR); return 2 * base_rq * (IOPRIO_BE_NR - cfqq->ioprio); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4595.74%250.00%
Namhyung Kim12.13%125.00%
Andrew Morton12.13%125.00%
Total47100.00%4100.00%

/* * Must be called with the queue_lock held. */
static int cfqq_process_refs(struct cfq_queue *cfqq) { int process_refs, io_refs; io_refs = cfqq->allocated[READ] + cfqq->allocated[WRITE]; process_refs = cfqq->ref - io_refs; BUG_ON(process_refs < 0); return process_refs; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Moyer50100.00%1100.00%
Total50100.00%1100.00%


static void cfq_setup_merge(struct cfq_queue *cfqq, struct cfq_queue *new_cfqq) { int process_refs, new_process_refs; struct cfq_queue *__cfqq; /* * If there are no process references on the new_cfqq, then it is * unsafe to follow the ->new_cfqq chain as other cfqq's in the * chain may have dropped their last reference (not just their * last process reference). */ if (!cfqq_process_refs(new_cfqq)) return; /* Avoid a circular list and skip interim queue merges */ while ((__cfqq = new_cfqq->new_cfqq)) { if (__cfqq == cfqq) return; new_cfqq = __cfqq; } process_refs = cfqq_process_refs(cfqq); new_process_refs = cfqq_process_refs(new_cfqq); /* * If the process for the cfqq has gone away, there is no * sense in merging the queues. */ if (process_refs == 0 || new_process_refs == 0) return; /* * Merge in the direction of the lesser amount of work. */ if (new_process_refs >= process_refs) { cfqq->new_cfqq = new_cfqq; new_cfqq->ref += process_refs; } else { new_cfqq->new_cfqq = cfqq; cfqq->ref += new_process_refs; } }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Moyer7460.66%360.00%
Corrado Zoccolo4436.07%120.00%
David Shaohua Li43.28%120.00%
Total122100.00%5100.00%


static enum wl_type_t cfq_choose_wl_type(struct cfq_data *cfqd, struct cfq_group *cfqg, enum wl_class_t wl_class) { struct cfq_queue *queue; int i; bool key_valid = false; u64 lowest_key = 0; enum wl_type_t cur_best = SYNC_NOIDLE_WORKLOAD; for (i = 0; i <= SYNC_WORKLOAD; ++i) { /* select the one with lowest rb_key */ queue = cfq_rb_first(st_for(cfqg, wl_class, i)); if (queue && (!key_valid || queue->rb_key < lowest_key)) { lowest_key = queue->rb_key; cur_best = i; key_valid = true; } } return cur_best; }

Contributors

PersonTokensPropCommitsCommitProp
Corrado Zoccolo9284.40%114.29%
Vivek Goyal1513.76%571.43%
Jeff Moyer21.83%114.29%
Total109100.00%7100.00%


static void choose_wl_class_and_type(struct cfq_data *cfqd, struct cfq_group *cfqg) { u64 slice; unsigned count; struct cfq_rb_root *st; u64 group_slice; enum wl_class_t original_class = cfqd->serving_wl_class; u64 now = ktime_get_ns(); /* Choose next priority. RT > BE > IDLE */ if (cfq_group_busy_queues_wl(RT_WORKLOAD, cfqd, cfqg)) cfqd->serving_wl_class = RT_WORKLOAD; else if (cfq_group_busy_queues_wl(BE_WORKLOAD, cfqd, cfqg)) cfqd->serving_wl_class = BE_WORKLOAD; else { cfqd->serving_wl_class = IDLE_WORKLOAD; cfqd->workload_expires = now + jiffies_to_nsecs(1); return; } if (original_class != cfqd->serving_wl_class) goto new_workload; /* * For RT and BE, we have to choose also the type * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload * expiration time */ st = st_for(cfqg, cfqd->serving_wl_class, cfqd->serving_wl_type); count = st->count; /* * check workload expiration, and that we still have other queues ready */ if (count && !(now > cfqd->workload_expires)) return; new_workload: /* otherwise select new workload type */ cfqd->serving_wl_type = cfq_choose_wl_type(cfqd, cfqg, cfqd->serving_wl_class); st = st_for(cfqg, cfqd->serving_wl_class, cfqd->serving_wl_type); count = st->count; /* * the workload slice is computed as a fraction of target latency * proportional to the number of queues in that workload, over * all the queues in the same priority class */ group_slice = cfq_group_slice(cfqd, cfqg); slice = div_u64(group_slice * count, max_t(unsigned, cfqg->busy_queues_avg[cfqd->serving_wl_class], cfq_group_busy_queues_wl(cfqd->serving_wl_class, cfqd, cfqg))); if (cfqd->serving_wl_type == ASYNC_WORKLOAD) { u64 tmp; /* * Async queues are currently system wide. Just taking * proportion of queues with-in same group will lead to higher * async ratio system wide as generally root group is going * to have higher weight. A more accurate thing would be to * calculate system wide asnc/sync ratio. */ tmp = cfqd->cfq_target_latency * cfqg_busy_async_queues(cfqd, cfqg); tmp = div_u64(tmp, cfqd->busy_queues); slice = min_t(u64, slice, tmp); /* async workload slice is scaled down according to * the sync/async slice ratio. */ slice = div64_u64(slice*cfqd->cfq_slice[0], cfqd->cfq_slice[1]); } else /* sync workload slice is at least 2 * cfq_slice_idle */ slice = max(slice, 2 * cfqd->cfq_slice_idle); slice = max_t(u64, slice, CFQ_MIN_TT); cfq_log(cfqd, "workload slice:%llu", slice); cfqd->workload_expires = now + slice; }

Contributors

PersonTokensPropCommitsCommitProp
Corrado Zoccolo15544.80%16.25%
Vivek Goyal10530.35%956.25%
Jeff Moyer6217.92%318.75%
David Shaohua Li144.05%16.25%
Divyesh Shah82.31%16.25%
Tao Ma20.58%16.25%
Total346100.00%16100.00%


static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd) { struct cfq_rb_root *st = &cfqd->grp_service_tree; struct cfq_group *cfqg; if (RB_EMPTY_ROOT(&st->rb)) return NULL; cfqg = cfq_rb_first_group(st); update_min_vdisktime(st); return cfqg; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal56100.00%2100.00%
Total56100.00%2100.00%


static void cfq_choose_cfqg(struct cfq_data *cfqd) { struct cfq_group *cfqg = cfq_get_next_cfqg(cfqd); u64 now = ktime_get_ns(); cfqd->serving_group = cfqg; /* Restore the workload type data */ if (cfqg->saved_wl_slice) { cfqd->workload_expires = now + cfqg->saved_wl_slice; cfqd->serving_wl_type = cfqg->saved_wl_type; cfqd->serving_wl_class = cfqg->saved_wl_class; } else cfqd->workload_expires = now - 1; choose_wl_class_and_type(cfqd, cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal6880.95%571.43%
Gui Jianfeng89.52%114.29%
Jeff Moyer89.52%114.29%
Total84100.00%7100.00%

/* * Select a queue for service. If we have a current active queue, * check whether to continue servicing it, or retrieve and set a new one. */
static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) { struct cfq_queue *cfqq, *new_cfqq = NULL; u64 now = ktime_get_ns(); cfqq = cfqd->active_queue; if (!cfqq) goto new_queue; if (!cfqd->rq_queued) return NULL; /* * We were waiting for group to get backlogged. Expire the queue */ if (cfq_cfqq_wait_busy(cfqq) && !RB_EMPTY_ROOT(&cfqq->sort_list)) goto expire; /* * The active queue has run out of time, expire it and select new. */ if (cfq_slice_used(cfqq) && !cfq_cfqq_must_dispatch(cfqq)) { /* * If slice had not expired at the completion of last request * we might not have turned on wait_busy flag. Don't expire * the queue yet. Allow the group to get backlogged. * * The very fact that we have used the slice, that means we * have been idling all along on this queue and it should be * ok to wait for this request to complete. */ if (cfqq->cfqg->nr_cfqq == 1 && RB_EMPTY_ROOT(&cfqq->sort_list) && cfqq->dispatched && cfq_should_idle(cfqd, cfqq)) { cfqq = NULL; goto keep_queue; } else goto check_group_idle; } /* * The active queue has requests and isn't expired, allow it to * dispatch. */ if (!RB_EMPTY_ROOT(&cfqq->sort_list)) goto keep_queue; /* * If another queue has a request waiting within our mean seek * distance, let it run. The expire code will check for close * cooperators and put the close queue at the front of the service * tree. If possible, merge the expiring queue with the new cfqq. */ new_cfqq = cfq_close_cooperator(cfqd, cfqq); if (new_cfqq) { if (!cfqq->new_cfqq) cfq_setup_merge(cfqq, new_cfqq); goto expire; } /* * No requests pending. If the active queue still has requests in * flight or is idling for a new request, allow either of these * conditions to happen (or time out) before selecting a new queue. */ if (hrtimer_active(&cfqd->idle_slice_timer)) { cfqq = NULL; goto keep_queue; } /* * This is a deep seek queue, but the device is much faster than * the queue can deliver, don't idle **/ if (CFQQ_SEEKY(cfqq) && cfq_cfqq_idle_window(cfqq) && (cfq_cfqq_slice_new(cfqq) || (cfqq->slice_end - now > now - cfqq->slice_start))) { cfq_clear_cfqq_deep(cfqq); cfq_clear_cfqq_idle_window(cfqq); } if (cfqq->dispatched && cfq_should_idle(cfqd, cfqq)) { cfqq = NULL; goto keep_queue; } /* * If group idle is enabled and there are requests dispatched from * this group, wait for requests to complete. */ check_group_idle: if (cfqd->cfq_group_idle && cfqq->cfqg->nr_cfqq == 1 && cfqq->cfqg->dispatched && !cfq_io_thinktime_big(cfqd, &cfqq->cfqg->ttime, true)) { cfqq = NULL; goto keep_queue; } expire: cfq_slice_expired(cfqd, 0); new_queue: /* * Current queue expired. Check if we have to switch to a new * service tree */ if (!new_cfqq) cfq_choose_cfqg(cfqd); cfqq = cfq_set_active_queue(cfqd, new_cfqq); keep_queue: return cfqq; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe13337.89%937.50%
Vivek Goyal12034.19%729.17%
David Shaohua Li5916.81%28.33%
Jeff Moyer257.12%28.33%
Corrado Zoccolo133.70%312.50%
Jan Kara10.28%14.17%
Total351100.00%24100.00%


static int __cfq_forced_dispatch_cfqq(struct cfq_queue *cfqq) { int dispatched = 0; while (cfqq->next_rq) { cfq_dispatch_insert(cfqq->cfqd->queue, cfqq->next_rq); dispatched++; } BUG_ON(!list_empty(&cfqq->fifo)); /* By default cfqq is not expired if it is empty. Do it explicitly */ __cfq_slice_expired(cfqq->cfqd, cfqq, 0); return dispatched; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo4161.19%114.29%
Jens Axboe1420.90%571.43%
Vivek Goyal1217.91%114.29%
Total67100.00%7100.00%

/* * Drain our current requests. Used for barriers and when switching * io schedulers on-the-fly. */
static int cfq_forced_dispatch(struct cfq_data *cfqd) { struct cfq_queue *cfqq; int dispatched = 0; /* Expire the timeslice of the current active queue first */ cfq_slice_expired(cfqd, 0); while ((cfqq = cfq_get_next_queue_forced(cfqd)) != NULL) { __cfq_set_active_queue(cfqd, cfqq); dispatched += __cfq_forced_dispatch_cfqq(cfqq); } BUG_ON(cfqd->busy_queues); cfq_log(cfqd, "forced_dispatch=%d", dispatched); return dispatched; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo2937.66%112.50%
Jens Axboe2228.57%337.50%
Divyesh Shah1722.08%112.50%
Corrado Zoccolo67.79%112.50%
Vivek Goyal22.60%112.50%
Jeff Moyer11.30%112.50%
Total77100.00%8100.00%


static inline bool cfq_slice_used_soon(struct cfq_data *cfqd, struct cfq_queue *cfqq) { u64 now = ktime_get_ns(); /* the queue hasn't finished any request, can't estimate */ if (cfq_cfqq_slice_new(cfqq)) return true; if (now + cfqd->cfq_slice_idle * cfqq->dispatched > cfqq->slice_end) return true; return false; }

Contributors

PersonTokensPropCommitsCommitProp
David Shaohua Li4885.71%266.67%
Jeff Moyer814.29%133.33%
Total56100.00%3100.00%


static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq) { unsigned int max_dispatch; if (cfq_cfqq_must_dispatch(cfqq)) return true; /* * Drain async requests before we start sync IO */ if (cfq_should_idle(cfqd, cfqq) && cfqd->rq_in_flight[BLK_RW_ASYNC]) return false; /* * If this is an async queue and we have sync IO in flight, let it wait */ if (cfqd->rq_in_flight[BLK_RW_SYNC] && !cfq_cfqq_sync(cfqq)) return false; max_dispatch = max_t(unsigned int, cfqd->cfq_quantum / 2, 1); if (cfq_class_idle(cfqq)) max_dispatch = 1; /* * Does this cfqq already have too much IO in flight? */ if (cfqq->dispatched >= max_dispatch) { bool promote_sync = false; /* * idle queue must always only have a single IO in flight */ if (cfq_class_idle(cfqq)) return false; /* * If there is only one sync queue * we can ignore async queue here and give the sync * queue no dispatch limit. The reason is a sync queue can * preempt async queue, limiting the sync queue doesn't make * sense. This is useful for aiostress test. */ if (cfq_cfqq_sync(cfqq) && cfqd->busy_sync_queues == 1) promote_sync = true; /* * We have other queues, don't allow more IO from this one */ if (cfqd->busy_queues > 1 && cfq_slice_used_soon(cfqd, cfqq) && !promote_sync) return false; /* * Sole queue user, no limit */ if (cfqd->busy_queues == 1 || promote_sync) max_dispatch = -1; else /* * Normally we start throttling cfqq when cfq_quantum/2 * requests have been dispatched. But we can drive * deeper queue depths at the beginning of slice * subjected to upper limit of cfq_quantum. * */ max_dispatch = cfqd->cfq_quantum; } /* * Async queues must wait a bit before being allowed dispatch. * We also ramp up the dispatch depth gradually for async IO, * based on the last sync IO we serviced */ if (!cfq_cfqq_sync(cfqq) && cfqd->cfq_latency) { u64 last_sync = ktime_get_ns() - cfqd->last_delayed_sync; unsigned int depth; depth = div64_u64(last_sync, cfqd->cfq_slice[1]); if (!depth && !cfqq->dispatched) depth = 1; if (depth < max_dispatch) max_dispatch = depth; } /* * If we're below the current max, allow a dispatch */ return cfqq->dispatched < max_dispatch; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe16865.12%110.00%
David Shaohua Li6424.81%440.00%
Glauber de Oliveira Costa103.88%110.00%
Corrado Zoccolo93.49%330.00%
Jeff Moyer72.71%110.00%
Total258100.00%10100.00%

/* * Dispatch a request from cfqq, moving them to the request queue * dispatch list. */
static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq) { struct request *rq; BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list)); rq = cfq_check_fifo(cfqq); if (rq) cfq_mark_cfqq_must_dispatch(cfqq); if (!cfq_may_dispatch(cfqd, cfqq)) return false; /* * follow expired path, else get first next available */ if (!rq) rq = cfqq->next_rq; else cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq); /* * insert request into driver dispatch list */ cfq_dispatch_insert(cfqd->queue, rq); if (!cfqd->active_cic) { struct cfq_io_cq *cic = RQ_CIC(rq); atomic_long_inc(&cic->icq.ioc->refcount); cfqd->active_cic = cic; } return true; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe10375.18%240.00%
Glauber de Oliveira Costa3021.90%120.00%
Tejun Heo32.19%120.00%
Nikanth Karthikesan10.73%120.00%
Total137100.00%5100.00%

/* * Find the cfqq that we need to service and move a request from that to the * dispatch list */
static int cfq_dispatch_requests(struct request_queue *q, int force) { struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_queue *cfqq; if (!cfqd->busy_queues) return 0; if (unlikely(force)) return cfq_forced_dispatch(cfqd); cfqq = cfq_select_queue(cfqd); if (!cfqq) return 0; /* * Dispatch a request from this cfqq, if it is allowed */ if (!cfq_dispatch_request(cfqd, cfqq)) return 0; cfqq->slice_dispatch++; cfq_clear_cfqq_must_dispatch(cfqq); /* * expire an async queue immediately if it has used up its slice. idle * queue always expire after 1 dispatch round. */ if (cfqd->busy_queues > 1 && ((!cfq_cfqq_sync(cfqq) && cfqq->slice_dispatch >= cfq_prio_to_maxrq(cfqd, cfqq)) || cfq_class_idle(cfqq))) { cfqq->slice_end = ktime_get_ns() + 1; cfq_slice_expired(cfqd, 0); } cfq_log_cfqq(cfqd, cfqq, "dispatched a request"); return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe13585.99%1477.78%
Tejun Heo159.55%15.56%
Shan Wei31.91%15.56%
Vivek Goyal21.27%15.56%
Jeff Moyer21.27%15.56%
Total157100.00%18100.00%

/* * task holds one reference to the queue, dropped when task exits. each rq * in-flight on this queue also holds a reference, dropped when rq is freed. * * Each cfq queue took a reference on the parent group. Drop it now. * queue lock must be held here. */
static void cfq_put_queue(struct cfq_queue *cfqq) { struct cfq_data *cfqd = cfqq->cfqd; struct cfq_group *cfqg; BUG_ON(cfqq->ref <= 0); cfqq->ref--; if (cfqq->ref) return; cfq_log_cfqq(cfqd, cfqq, "put_queue"); BUG_ON(rb_first(&cfqq->sort_list)); BUG_ON(cfqq->allocated[READ] + cfqq->allocated[WRITE]); cfqg = cfqq->cfqg; if (unlikely(cfqd->active_queue == cfqq)) { __cfq_slice_expired(cfqd, cfqq, 0); cfq_schedule_dispatch(cfqd); } BUG_ON(cfq_cfqq_on_rr(cfqq)); kmem_cache_free(cfq_pool, cfqq); cfqg_put(cfqg); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe8159.56%550.00%
Vasily Tarasov2619.12%110.00%
Vivek Goyal2316.91%220.00%
David Shaohua Li53.68%110.00%
Tejun Heo10.74%110.00%
Total136100.00%10100.00%


static void cfq_put_cooperator(struct cfq_queue *cfqq) { struct cfq_queue *__cfqq, *next; /* * If this queue was scheduled to merge with another queue, be * sure to drop the reference taken on that queue (and others in * the merge chain). See cfq_setup_merge and cfq_merge_cfqqs. */ __cfqq = cfqq->new_cfqq; while (__cfqq) { if (__cfqq == cfqq) { WARN(1, "cfqq->new_cfqq loop detected\n"); break; } next = __cfqq->new_cfqq; cfq_put_queue(__cfqq); __cfqq = next; } }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Moyer5282.54%120.00%
Jens Axboe711.11%240.00%
Al Viro23.17%120.00%
David Shaohua Li23.17%120.00%
Total63100.00%5100.00%


static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (unlikely(cfqq == cfqd->active_queue)) { __cfq_slice_expired(cfqd, cfqq, 0); cfq_schedule_dispatch(cfqd); } cfq_put_cooperator(cfqq); cfq_put_queue(cfqq); }

Contributors

PersonTokensPropCommitsCommitProp
David Shaohua Li4788.68%133.33%
Jens Axboe47.55%133.33%
Al Viro23.77%133.33%
Total53100.00%3100.00%


static void cfq_init_icq(struct io_cq *icq) { struct cfq_io_cq *cic = icq_to_cic(icq); cic->ttime.last_end_request = ktime_get_ns(); }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo2893.33%150.00%
Jeff Moyer26.67%150.00%
Total30100.00%2100.00%


static void cfq_exit_icq(struct io_cq *icq) { struct cfq_io_cq *cic = icq_to_cic(icq); struct cfq_data *cfqd = cic_to_cfqd(cic); if (cic_to_cfqq(cic, false)) { cfq_exit_cfqq(cfqd, cic_to_cfqq(cic, false)); cic_set_cfqq(cic, NULL, false); } if (cic_to_cfqq(cic, true)) { cfq_exit_cfqq(cfqd, cic_to_cfqq(cic, true)); cic_set_cfqq(cic, NULL, true); } }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo5456.84%333.33%
Jens Axboe2526.32%444.44%
Al Viro1313.68%111.11%
Fabio Checconi33.16%111.11%
Total95100.00%9100.00%


static void cfq_init_prio_data(struct cfq_queue *cfqq, struct cfq_io_cq *cic) { struct task_struct *tsk = current; int ioprio_class; if (!cfq_cfqq_prio_changed(cfqq)) return; ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); switch (ioprio_class) { default: printk(KERN_ERR "cfq: bad prio %x\n", ioprio_class); case IOPRIO_CLASS_NONE: /* * no prio set, inherit CPU scheduling settings */ cfqq->ioprio = task_nice_ioprio(tsk); cfqq->ioprio_class = task_nice_ioclass(tsk); break; case IOPRIO_CLASS_RT: cfqq->ioprio = IOPRIO_PRIO_DATA(cic->ioprio); cfqq->ioprio_class = IOPRIO_CLASS_RT; break; case IOPRIO_CLASS_BE: cfqq->ioprio = IOPRIO_PRIO_DATA(cic->ioprio); cfqq->ioprio_class = IOPRIO_CLASS_BE; break; case IOPRIO_CLASS_IDLE: cfqq->ioprio_class = IOPRIO_CLASS_IDLE; cfqq->ioprio = 7; cfq_clear_cfqq_idle_window(cfqq); break; } /* * keep track of original prio settings in case we have to temporarily * elevate the priority of this queue */ cfqq->org_ioprio = cfqq->ioprio; cfqq->org_ioprio_class = cfqq->ioprio_class; cfq_clear_cfqq_prio_changed(cfqq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe15592.81%675.00%
Tejun Heo127.19%225.00%
Total167100.00%8100.00%


static void check_ioprio_changed(struct cfq_io_cq *cic, struct bio *bio) { int ioprio = cic->icq.ioc->ioprio; struct cfq_data *cfqd = cic_to_cfqd(cic); struct cfq_queue *cfqq; /* * Check whether ioprio has changed. The condition may trigger * spuriously on a newly created cic but there's no harm. */ if (unlikely(!cfqd) || likely(cic->ioprio == ioprio)) return; cfqq = cic_to_cfqq(cic, false); if (cfqq) { cfq_put_queue(cfqq); cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic, bio); cic_set_cfqq(cic, cfqq, false); } cfqq = cic_to_cfqq(cic, true); if (cfqq) cfq_mark_cfqq_prio_changed(cfqq); cic->ioprio = ioprio; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo5644.09%430.77%
Al Viro4333.86%323.08%
Jens Axboe2519.69%538.46%
Konstantin Khlebnikov32.36%17.69%
Total127100.00%13100.00%


static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq, pid_t pid, bool is_sync) { RB_CLEAR_NODE(&cfqq->rb_node); RB_CLEAR_NODE(&cfqq->p_node); INIT_LIST_HEAD(&cfqq->fifo); cfqq->ref = 0; cfqq->cfqd = cfqd; cfq_mark_cfqq_prio_changed(cfqq); if (is_sync) { if (!cfq_class_idle(cfqq)) cfq_mark_cfqq_idle_window(cfqq); cfq_mark_cfqq_sync(cfqq); } cfqq->pid = pid; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe9298.92%266.67%
David Shaohua Li11.08%133.33%
Total93100.00%3100.00%

#ifdef CONFIG_CFQ_GROUP_IOSCHED
static void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio) { struct cfq_data *cfqd = cic_to_cfqd(cic); struct cfq_queue *cfqq; uint64_t serial_nr; rcu_read_lock(); serial_nr = bio_blkcg(bio)->css.serial_nr; rcu_read_unlock(); /* * Check whether blkcg has changed. The condition may trigger * spuriously on a newly created cic but there's no harm. */ if (unlikely(!cfqd) || likely(cic->blkcg_serial_nr == serial_nr)) return; /* * Drop reference to queues. New queues will be assigned in new * group upon arrival of fresh requests. */ cfqq = cic_to_cfqq(cic, false); if (cfqq) { cfq_log_cfqq(cfqd, cfqq, "changed cgroup"); cic_set_cfqq(cic, NULL, false); cfq_put_queue(cfqq); } cfqq = cic_to_cfqq(cic, true); if (cfqq) { cfq_log_cfqq(cfqd, cfqq, "changed cgroup"); cic_set_cfqq(cic, NULL, true); cfq_put_queue(cfqq); } cic->blkcg_serial_nr = serial_nr; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo9562.09%562.50%
Vivek Goyal5334.64%112.50%
Konstantin Khlebnikov31.96%112.50%
Jan Kara21.31%112.50%
Total153100.00%8100.00%

#else
static inline void check_blkcg_changed(struct cfq_io_cq *cic, struct bio *bio) { }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo1487.50%150.00%
Jan Kara212.50%150.00%
Total16100.00%2100.00%

#endif /* CONFIG_CFQ_GROUP_IOSCHED */
static struct cfq_queue ** cfq_async_queue_prio(struct cfq_group *cfqg, int ioprio_class, int ioprio) { switch (ioprio_class) { case IOPRIO_CLASS_RT: return &cfqg->async_cfqq[0][ioprio]; case IOPRIO_CLASS_NONE: ioprio = IOPRIO_NORM; /* fall through */ case IOPRIO_CLASS_BE: return &cfqg->async_cfqq[1][ioprio]; case IOPRIO_CLASS_IDLE: return &cfqg->async_idle_cfqq; default: BUG(); } }

Contributors

PersonTokensPropCommitsCommitProp
Vasily Tarasov6077.92%120.00%
Tejun Heo1316.88%240.00%
Jens Axboe45.19%240.00%
Total77100.00%5100.00%


static struct cfq_queue * cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, struct bio *bio) { int ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); int ioprio = IOPRIO_PRIO_DATA(cic->ioprio); struct cfq_queue **async_cfqq = NULL; struct cfq_queue *cfqq; struct cfq_group *cfqg; rcu_read_lock(); cfqg = cfq_lookup_cfqg(cfqd, bio_blkcg(bio)); if (!cfqg) { cfqq = &cfqd->oom_cfqq; goto out; } if (!is_sync) { if (!ioprio_valid(cic->ioprio)) { struct task_struct *tsk = current; ioprio = task_nice_ioprio(tsk); ioprio_class = task_nice_ioclass(tsk); } async_cfqq = cfq_async_queue_prio(cfqg, ioprio_class, ioprio); cfqq = *async_cfqq; if (cfqq) goto out; } cfqq = kmem_cache_alloc_node(cfq_pool, GFP_NOWAIT | __GFP_ZERO | __GFP_NOWARN, cfqd->queue->node); if (!cfqq) { cfqq = &cfqd->oom_cfqq; goto out; } /* cfq_init_cfqq() assumes cfqq->ioprio_class is initialized. */ cfqq->ioprio_class = IOPRIO_CLASS_NONE; cfq_init_cfqq(cfqd, cfqq, current->pid, is_sync); cfq_init_prio_data(cfqq, cic); cfq_link_cfqq_cfqg(cfqq, cfqg); cfq_log_cfqq(cfqd, cfqq, "alloced"); if (async_cfqq) { /* a new async queue is created, pin and remember */ cfqq->ref++; *async_cfqq = cfqq; } out: cfqq->ref++; rcu_read_unlock(); return cfqq; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo13148.88%1062.50%
Jens Axboe6624.63%212.50%
Jeff Moyer3312.31%16.25%
Vasily Tarasov2910.82%16.25%
Alexander Potapenko72.61%16.25%
David Shaohua Li20.75%16.25%
Total268100.00%16100.00%


static void __cfq_update_io_thinktime(struct cfq_ttime *ttime, u64 slice_idle) { u64 elapsed = ktime_get_ns() - ttime->last_end_request; elapsed = min(elapsed, 2UL * slice_idle); ttime->ttime_samples = (7*ttime->ttime_samples + 256) / 8; ttime->ttime_total = div_u64(7*ttime->ttime_total + 256*elapsed, 8); ttime->ttime_mean = div64_ul(ttime->ttime_total + 128, ttime->ttime_samples); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe5866.67%250.00%
David Shaohua Li1719.54%125.00%
Jeff Moyer1213.79%125.00%
Total87100.00%4100.00%


static void cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct cfq_io_cq *cic) { if (cfq_cfqq_sync(cfqq)) { __cfq_update_io_thinktime(&cic->ttime, cfqd->cfq_slice_idle); __cfq_update_io_thinktime(&cfqq->service_tree->ttime, cfqd->cfq_slice_idle); } #ifdef CONFIG_CFQ_GROUP_IOSCHED __cfq_update_io_thinktime(&cfqq->cfqg->ttime, cfqd->cfq_group_idle); #endif }

Contributors

PersonTokensPropCommitsCommitProp
David Shaohua Li7296.00%360.00%
Jens Axboe22.67%120.00%
Tejun Heo11.33%120.00%
Total75100.00%5100.00%


static void cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct request *rq) { sector_t sdist = 0; sector_t n_sec = blk_rq_sectors(rq); if (cfqq->last_request_pos) { if (cfqq->last_request_pos < blk_rq_pos(rq)) sdist = blk_rq_pos(rq) - cfqq->last_request_pos; else sdist = cfqq->last_request_pos - blk_rq_pos(rq); } cfqq->seek_history <<= 1; if (blk_queue_nonrot(cfqd->queue)) cfqq->seek_history |= (n_sec < CFQQ_SECT_THR_NONROT); else cfqq->seek_history |= (sdist > CFQQ_SEEK_THR); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4943.75%440.00%
Corrado Zoccolo3934.82%220.00%
Jeff Moyer1311.61%220.00%
Tejun Heo98.04%110.00%
David Shaohua Li21.79%110.00%
Total112100.00%10100.00%


static inline bool req_noidle(struct request *req) { return req_op(req) == REQ_OP_WRITE && (req->cmd_flags & (REQ_SYNC | REQ_IDLE)) == REQ_SYNC; }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig34100.00%1100.00%
Total34100.00%1100.00%

/* * Disable idle window if the process thinks too long or seeks so much that * it doesn't matter */
static void cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct cfq_io_cq *cic) { int old_idle, enable_idle; /* * Don't idle for async or idle io prio class */ if (!cfq_cfqq_sync(cfqq) || cfq_class_idle(cfqq)) return; enable_idle = old_idle = cfq_cfqq_idle_window(cfqq); if (cfqq->queued[0] + cfqq->queued[1] >= 4) cfq_mark_cfqq_deep(cfqq); if (cfqq->next_rq && req_noidle(cfqq->next_rq)) enable_idle = 0; else if (!atomic_read(&cic->icq.ioc->active_ref) || !cfqd->cfq_slice_idle || (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq))) enable_idle = 0; else if (sample_valid(cic->ttime.ttime_samples)) { if (cic->ttime.ttime_mean > cfqd->cfq_slice_idle) enable_idle = 0; else enable_idle = 1; } if (old_idle != enable_idle) { cfq_log_cfqq(cfqd, cfqq, "idle=%d", enable_idle); if (enable_idle) cfq_mark_cfqq_idle_window(cfqq); else cfq_clear_cfqq_idle_window(cfqq); } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe13367.51%847.06%
Corrado Zoccolo4723.86%317.65%
Tejun Heo42.03%211.76%
David Shaohua Li42.03%15.88%
Nikanth Karthikesan42.03%15.88%
Christoph Hellwig31.52%15.88%
Jeff Moyer21.02%15.88%
Total197100.00%17100.00%

/* * Check if new_cfqq should preempt the currently active queue. Return 0 for * no or if we aren't sure, a 1 will cause a preempt. */
static bool cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq, struct request *rq) { struct cfq_queue *cfqq; cfqq = cfqd->active_queue; if (!cfqq) return false; if (cfq_class_idle(new_cfqq)) return false; if (cfq_class_idle(cfqq)) return true; /* * Don't allow a non-RT request to preempt an ongoing RT cfqq timeslice. */ if (cfq_class_rt(cfqq) && !cfq_class_rt(new_cfqq)) return false; /* * if the new request is sync, but the currently running queue is * not, let the sync request have priority. */ if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq) && !cfq_cfqq_must_dispatch(cfqq)) return true; /* * Treat ancestors of current cgroup the same way as current cgroup. * For anybody else we disallow preemption to guarantee service * fairness among cgroups. */ if (!cfqg_is_descendant(cfqq->cfqg, new_cfqq->cfqg)) return false; if (cfq_slice_used(cfqq)) return true; /* * Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice. */ if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq)) return true; WARN_ON_ONCE(cfqq->ioprio_class != new_cfqq->ioprio_class); /* Allow preemption only if we are idling on sync-noidle tree */ if (cfqd->serving_wl_type == SYNC_NOIDLE_WORKLOAD && cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD && RB_EMPTY_ROOT(&cfqq->sort_list)) return true; /* * So both queues are sync. Let the new request get disk time if * it's a metadata request and the current queue is doing regular IO. */ if ((rq->cmd_flags & REQ_PRIO) && !cfqq->prio_pending) return true; /* An idle queue should not be idle now for some reason */ if (RB_EMPTY_ROOT(&cfqq->sort_list) && !cfq_should_idle(cfqd, cfqq)) return true; if (!cfqd->active_cic || !cfq_cfqq_wait_request(cfqq)) return false; /* * if this request is as-good as one we would expect from the * current cfqq, let it preempt */ if (cfq_rq_close(cfqd, cfqq, rq)) return true; return false; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe11544.57%633.33%
Vivek Goyal4015.50%316.67%
Jan Kara3613.95%211.11%
David Shaohua Li228.53%15.56%
Corrado Zoccolo186.98%211.11%
Divyesh Shah176.59%15.56%
Glauber de Oliveira Costa62.33%15.56%
Christoph Hellwig20.78%15.56%
Jeff Moyer20.78%15.56%
Total258100.00%18100.00%

/* * cfqq preempts the active queue. if we allowed preempt with no slice left, * let it have half of its nominal slice. */
static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq) { enum wl_type_t old_type = cfqq_type(cfqd->active_queue); cfq_log_cfqq(cfqd, cfqq, "preempt"); cfq_slice_expired(cfqd, 1); /* * workload type is changed, don't save slice, otherwise preempt * doesn't happen */ if (old_type != cfqq_type(cfqq)) cfqq->cfqg->saved_wl_slice = 0; /* * Put the new queue at the front of the of the current list, * so we know that it will be selected next. */ BUG_ON(!cfq_cfqq_on_rr(cfqq)); cfq_service_tree_add(cfqd, cfqq, 1); cfqq->slice_end = 0; cfq_mark_cfqq_slice_new(cfqq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4953.85%660.00%
David Shaohua Li3437.36%220.00%
Justin TerAvest77.69%110.00%
Vivek Goyal11.10%110.00%
Total91100.00%10100.00%

/* * Called when a new fs request (rq) is added (to cfqq). Check if there's * something we should do about it */
static void cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct request *rq) { struct cfq_io_cq *cic = RQ_CIC(rq); cfqd->rq_queued++; if (rq->cmd_flags & REQ_PRIO) cfqq->prio_pending++; cfq_update_io_thinktime(cfqd, cfqq, cic); cfq_update_io_seektime(cfqd, cfqq, rq); cfq_update_idle_window(cfqd, cfqq, cic); cfqq->last_request_pos = blk_rq_pos(rq) + blk_rq_sectors(rq); if (cfqq == cfqd->active_queue) { /* * Remember that we saw a request from this process, but * don't start queuing just yet. Otherwise we risk seeing lots * of tiny requests, because we disrupt the normal plugging * and merging. If the request is already larger than a single * page, let it rip immediately. For that case we assume that * merging is already done. Ditto for a busy system that * has other work pending, don't risk delaying until the * idle timer unplug to continue working. */ if (cfq_cfqq_wait_request(cfqq)) { if (blk_rq_bytes(rq) > PAGE_SIZE || cfqd->busy_queues > 1) { cfq_del_timer(cfqd, cfqq); cfq_clear_cfqq_wait_request(cfqq); __blk_run_queue(cfqd->queue); } else { cfqg_stats_update_idle_time(cfqq->cfqg); cfq_mark_cfqq_must_dispatch(cfqq); } } } else if (cfq_should_preempt(cfqd, cfqq, rq)) { /* * not the active queue - expire current slice if it is * idle and has expired it's mean thinktime or this new queue * has some old slice time left and is of higher priority or * this new queue is RT and the current one is BE */ cfq_preempt_queue(cfqd, cfqq); __blk_run_queue(cfqd->queue); } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe15078.95%1346.43%
Tejun Heo126.32%517.86%
Divyesh Shah105.26%310.71%
Gui Jianfeng52.63%13.57%
Aaron Carroll52.63%13.57%
Jeff Moyer21.05%13.57%
Christoph Hellwig21.05%13.57%
David Shaohua Li21.05%13.57%
Vivek Goyal10.53%13.57%
Kirill A. Shutemov10.53%13.57%
Total190100.00%28100.00%


static void cfq_insert_request(struct request_queue *q, struct request *rq) { struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_queue *cfqq = RQ_CFQQ(rq); cfq_log_cfqq(cfqd, cfqq, "insert_request"); cfq_init_prio_data(cfqq, RQ_CIC(rq)); rq->fifo_time = ktime_get_ns() + cfqd->cfq_fifo_expire[rq_is_sync(rq)]; list_add_tail(&rq->queuelist, &cfqq->fifo); cfq_add_rq_rb(rq); cfqg_stats_update_io_add(RQ_CFQG(rq), cfqd->serving_group, rq->cmd_flags); cfq_rq_enqueued(cfqd, cfqq, rq); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe9077.59%746.67%
Divyesh Shah76.03%16.67%
Corrado Zoccolo54.31%16.67%
Tejun Heo54.31%320.00%
Vivek Goyal43.45%16.67%
Jan Kara32.59%16.67%
Jeff Moyer21.72%16.67%
Total116100.00%15100.00%

/* * Update hw_tag based on peak queue depth over 50 samples under * sufficient load. */
static void cfq_update_hw_tag(struct cfq_data *cfqd) { struct cfq_queue *cfqq = cfqd->active_queue; if (cfqd->rq_in_driver > cfqd->hw_tag_est_depth) cfqd->hw_tag_est_depth = cfqd->rq_in_driver; if (cfqd->hw_tag == 1) return; if (cfqd->rq_queued <= CFQ_HW_QUEUE_MIN && cfqd->rq_in_driver <= CFQ_HW_QUEUE_MIN) return; /* * If active queue hasn't enough requests and can idle, cfq might not * dispatch sufficient requests to hardware. Don't zero hw_tag in this * case */ if (cfqq && cfq_cfqq_idle_window(cfqq) && cfqq->dispatched + cfqq->queued[0] + cfqq->queued[1] < CFQ_HW_QUEUE_MIN && cfqd->rq_in_driver < CFQ_HW_QUEUE_MIN) return; if (cfqd->hw_tag_samples++ < 50) return; if (cfqd->hw_tag_est_depth >= CFQ_HW_QUEUE_MIN) cfqd->hw_tag = 1; else cfqd->hw_tag = 0; }

Contributors

PersonTokensPropCommitsCommitProp
Aaron Carroll6348.46%120.00%
David Shaohua Li4433.85%120.00%
Corrado Zoccolo2015.38%240.00%
Jens Axboe32.31%120.00%
Total130100.00%5100.00%


static bool cfq_should_wait_busy(struct cfq_data *cfqd, struct cfq_queue *cfqq) { struct cfq_io_cq *cic = cfqd->active_cic; u64 now = ktime_get_ns(); /* If the queue already has requests, don't wait */ if (!RB_EMPTY_ROOT(&cfqq->sort_list)) return false; /* If there are other queues in the group, don't wait */ if (cfqq->cfqg->nr_cfqq > 1) return false; /* the only queue in the group, but think time is big */ if (cfq_io_thinktime_big(cfqd, &cfqq->cfqg->ttime, true)) return false; if (cfq_slice_used(cfqq)) return true; /* if slice left is less than think time, wait busy */ if (cic && sample_valid(cic->ttime.ttime_samples) && (cfqq->slice_end - now < cic->ttime.ttime_mean)) return true; /* * If think times is less than a jiffy than ttime_mean=0 and above * will not be true. It might happen that slice has not expired yet * but will expire soon (4-5 ns) during select_queue(). To cover the * case where think time is less than a jiffy, mark the queue wait * busy if only 1 jiffy is left in the slice. */ if (cfqq->slice_end - now <= jiffies_to_nsecs(1)) return true; return false; }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal8963.12%116.67%
David Shaohua Li2417.02%233.33%
Justin TerAvest1510.64%116.67%
Jeff Moyer128.51%116.67%
Tejun Heo10.71%116.67%
Total141100.00%6100.00%


static void cfq_completed_request(struct request_queue *q, struct request *rq) { struct cfq_queue *cfqq = RQ_CFQQ(rq); struct cfq_data *cfqd = cfqq->cfqd; const int sync = rq_is_sync(rq); u64 now = ktime_get_ns(); cfq_log_cfqq(cfqd, cfqq, "complete rqnoidle %d", req_noidle(rq)); cfq_update_hw_tag(cfqd); WARN_ON(!cfqd->rq_in_driver); WARN_ON(!cfqq->dispatched); cfqd->rq_in_driver--; cfqq->dispatched--; (RQ_CFQG(rq))->dispatched--; cfqg_stats_update_completion(cfqq->cfqg, rq_start_time_ns(rq), rq_io_start_time_ns(rq), rq->cmd_flags); cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--; if (sync) { struct cfq_rb_root *st; RQ_CIC(rq)->ttime.last_end_request = now; if (cfq_cfqq_on_rr(cfqq)) st = cfqq->service_tree; else st = st_for(cfqq->cfqg, cfqq_class(cfqq), cfqq_type(cfqq)); st->ttime.last_end_request = now; /* * We have to do this check in jiffies since start_time is in * jiffies and it is not trivial to convert to ns. If * cfq_fifo_expire[1] ever comes close to 1 jiffie, this test * will become problematic but so far we are fine (the default * is 128 ms). */ if (!time_after(rq->start_time + nsecs_to_jiffies(cfqd->cfq_fifo_expire[1]), jiffies)) cfqd->last_delayed_sync = now; } #ifdef CONFIG_CFQ_GROUP_IOSCHED cfqq->cfqg->ttime.last_end_request = now; #endif /* * If this is the active queue, check if it needs to be expired, * or if we want to idle in case it has no pending requests. */ if (cfqd->active_queue == cfqq) { const bool cfqq_empty = RB_EMPTY_ROOT(&cfqq->sort_list); if (cfq_cfqq_slice_new(cfqq)) { cfq_set_prio_slice(cfqd, cfqq); cfq_clear_cfqq_slice_new(cfqq); } /* * Should we wait for next request to come in before we expire * the queue. */ if (cfq_should_wait_busy(cfqd, cfqq)) { u64 extend_sl = cfqd->cfq_slice_idle; if (!cfqd->cfq_slice_idle) extend_sl = cfqd->cfq_group_idle; cfqq->slice_end = now + extend_sl; cfq_mark_cfqq_wait_busy(cfqq); cfq_log_cfqq(cfqd, cfqq, "will busy wait"); } /* * Idling is not enabled on: * - expired queues * - idle-priority queues * - async queues * - queues with still some requests queued * - when there is a close cooperator */ if (cfq_slice_used(cfqq) || cfq_class_idle(cfqq)) cfq_slice_expired(cfqd, 1); else if (sync && cfqq_empty && !cfq_close_cooperator(cfqd, cfqq)) { cfq_arm_slice_timer(cfqd); } } if (!cfqd->rq_in_driver) cfq_schedule_dispatch(cfqd); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe18947.73%1641.03%
Vivek Goyal6917.42%717.95%
David Shaohua Li5714.39%37.69%
Corrado Zoccolo287.07%37.69%
Divyesh Shah256.31%37.69%
Jan Kara92.27%12.56%
Jeff Moyer61.52%12.56%
Aaron Carroll51.26%12.56%
Tejun Heo51.26%37.69%
Christoph Hellwig30.76%12.56%
Total396100.00%39100.00%


static void cfqq_boost_on_prio(struct cfq_queue *cfqq, unsigned int op) { /* * If REQ_PRIO is set, boost class and prio level, if it's below * BE/NORM. If prio is not set, restore the potentially boosted * class/prio level. */ if (!(op & REQ_PRIO)) { cfqq->ioprio_class = cfqq->org_ioprio_class; cfqq->ioprio = cfqq->org_ioprio; } else { if (cfq_class_idle(cfqq)) cfqq->ioprio_class = IOPRIO_CLASS_BE; if (cfqq->ioprio > IOPRIO_NORM) cfqq->ioprio = IOPRIO_NORM; } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe7095.89%150.00%
Christoph Hellwig34.11%150.00%
Total73100.00%2100.00%


static inline int __cfq_may_queue(struct cfq_queue *cfqq) { if (cfq_cfqq_wait_request(cfqq) && !cfq_cfqq_must_alloc_slice(cfqq)) { cfq_mark_cfqq_must_alloc_slice(cfqq); return ELV_MQUEUE_MUST; } return ELV_MQUEUE_MAY; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe3592.11%266.67%
Andrew Morton37.89%133.33%
Total38100.00%3100.00%


static int cfq_may_queue(struct request_queue *q, unsigned int op) { struct cfq_data *cfqd = q->elevator->elevator_data; struct task_struct *tsk = current; struct cfq_io_cq *cic; struct cfq_queue *cfqq; /* * don't force setup of a queue from here, as a call to may_queue * does not necessarily imply that a request actually will be queued. * so just lookup a possibly existing queue, or return 'may queue' * if that fails */ cic = cfq_cic_lookup(cfqd, tsk->io_context); if (!cic) return ELV_MQUEUE_MAY; cfqq = cic_to_cfqq(cic, op_is_sync(op)); if (cfqq) { cfq_init_prio_data(cfqq, cic); cfqq_boost_on_prio(cfqq, op); return __cfq_may_queue(cfqq); } return ELV_MQUEUE_MAY; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe7875.00%866.67%
Vasily Tarasov2019.23%18.33%
Christoph Hellwig32.88%18.33%
Michael Christie21.92%18.33%
Tejun Heo10.96%18.33%
Total104100.00%12100.00%

/* * queue lock held here */
static void cfq_put_request(struct request *rq) { struct cfq_queue *cfqq = RQ_CFQQ(rq); if (cfqq) { const int rw = rq_data_dir(rq); BUG_ON(!cfqq->allocated[rw]); cfqq->allocated[rw]--; /* Put down rq reference on cfqg */ cfqg_put(RQ_CFQG(rq)); rq->elv.priv[0] = NULL; rq->elv.priv[1] = NULL; cfq_put_queue(cfqq); } }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe6065.93%342.86%
Tejun Heo1617.58%228.57%
Vivek Goyal1314.29%114.29%
Mike Snitzer22.20%114.29%
Total91100.00%7100.00%


static struct cfq_queue * cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_cq *cic, struct cfq_queue *cfqq) { cfq_log_cfqq(cfqd, cfqq, "merging with queue %p", cfqq->new_cfqq); cic_set_cfqq(cic, cfqq->new_cfqq, 1); cfq_mark_cfqq_coop(cfqq->new_cfqq); cfq_put_queue(cfqq); return cic_to_cfqq(cic, 1); }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Moyer6698.51%266.67%
Tejun Heo11.49%133.33%
Total67100.00%3100.00%

/* * Returns NULL if a new cfqq should be allocated, or the old cfqq if this * was the last process referring to said cfqq. */
static struct cfq_queue * split_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq) { if (cfqq_process_refs(cfqq) == 1) { cfqq->pid = current->pid; cfq_clear_cfqq_coop(cfqq); cfq_clear_cfqq_split_coop(cfqq); return cfqq; } cic_set_cfqq(cic, NULL, 1); cfq_put_cooperator(cfqq); cfq_put_queue(cfqq); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Jeff Moyer6184.72%125.00%
David Shaohua Li1013.89%250.00%
Tejun Heo11.39%125.00%
Total72100.00%4100.00%

/* * Allocate cfq data structures associated with this request. */
static int cfq_set_request(struct request_queue *q, struct request *rq, struct bio *bio, gfp_t gfp_mask) { struct cfq_data *cfqd = q->elevator->elevator_data; struct cfq_io_cq *cic = icq_to_cic(rq->elv.icq); const int rw = rq_data_dir(rq); const bool is_sync = rq_is_sync(rq); struct cfq_queue *cfqq; spin_lock_irq(q->queue_lock); check_ioprio_changed(cic, bio); check_blkcg_changed(cic, bio); new_queue: cfqq = cic_to_cfqq(cic, is_sync); if (!cfqq || cfqq == &cfqd->oom_cfqq) { if (cfqq) cfq_put_queue(cfqq); cfqq = cfq_get_queue(cfqd, is_sync, cic, bio); cic_set_cfqq(cic, cfqq, is_sync); } else { /* * If the queue was seeky for too long, break it apart. */ if (cfq_cfqq_coop(cfqq) && cfq_cfqq_split_coop(cfqq)) { cfq_log_cfqq(cfqd, cfqq, "breaking apart cfqq"); cfqq = split_cfqq(cic, cfqq); if (!cfqq) goto new_queue; } /* * Check to see if this queue is scheduled to merge with * another, closely cooperating queue. The merging of * queues happens here as it must be done in process context. * The reference on new_cfqq was taken in merge_cfqqs. */ if (cfqq->new_cfqq) cfqq = cfq_merge_cfqqs(cfqd, cic, cfqq); } cfqq->allocated[rw]++; cfqq->ref++; cfqg_get(cfqq->cfqg); rq->elv.priv[0] = cfqq; rq->elv.priv[1] = cfqq->cfqg; spin_unlock_irq(q->queue_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe10539.62%931.03%
Jeff Moyer6323.77%26.90%
Tejun Heo6022.64%1034.48%
Vasily Tarasov155.66%13.45%
Vivek Goyal145.28%26.90%
Mike Snitzer41.51%13.45%
Al Viro20.75%26.90%
David Shaohua Li20.75%26.90%
Total265100.00%29100.00%


static void cfq_kick_queue(struct work_struct *work) { struct cfq_data *cfqd = container_of(work, struct cfq_data, unplug_work); struct request_queue *q = cfqd->queue; spin_lock_irq(q->queue_lock); __blk_run_queue(cfqd->queue); spin_unlock_irq(q->queue_lock); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe3155.36%466.67%
David Howells2137.50%116.67%
Tejun Heo47.14%116.67%
Total56100.00%6100.00%

/* * Timer running if the active_queue is currently idling inside its time slice */
static enum hrtimer_restart cfq_idle_slice_timer(struct hrtimer *timer) { struct cfq_data *cfqd = container_of(timer, struct cfq_data, idle_slice_timer); struct cfq_queue *cfqq; unsigned long flags; int timed_out = 1; cfq_log(cfqd, "idle timer fired"); spin_lock_irqsave(cfqd->queue->queue_lock, flags); cfqq = cfqd->active_queue; if (cfqq) { timed_out = 0; /* * We saw a request before the queue expired, let it through */ if (cfq_cfqq_must_dispatch(cfqq)) goto out_kick; /* * expired */ if (cfq_slice_used(cfqq)) goto expire; /* * only expire and reinvoke request handler, if there are * other queues with pending requests */ if (!cfqd->busy_queues) goto out_cont; /* * not expired and it has a request pending, let it dispatch */ if (!RB_EMPTY_ROOT(&cfqq->sort_list)) goto out_kick; /* * Queue depth flag is reset only when the idle didn't succeed */ cfq_clear_cfqq_deep(cfqq); } expire: cfq_slice_expired(cfqd, timed_out); out_kick: cfq_schedule_dispatch(cfqd); out_cont: spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); return HRTIMER_NORESTART; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe13986.34%1184.62%
Jan Kara169.94%17.69%
Corrado Zoccolo63.73%17.69%
Total161100.00%13100.00%


static void cfq_shutdown_timer_wq(struct cfq_data *cfqd) { hrtimer_cancel(&cfqd->idle_slice_timer); cancel_work_sync(&cfqd->unplug_work); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe2488.89%250.00%
Oleg Nesterov27.41%125.00%
Jan Kara13.70%125.00%
Total27100.00%4100.00%


static void cfq_exit_queue(struct elevator_queue *e) { struct cfq_data *cfqd = e->elevator_data; struct request_queue *q = cfqd->queue; cfq_shutdown_timer_wq(cfqd); spin_lock_irq(q->queue_lock); if (cfqd->active_queue) __cfq_slice_expired(cfqd, cfqd->active_queue, 0); spin_unlock_irq(q->queue_lock); cfq_shutdown_timer_wq(cfqd); #ifdef CONFIG_CFQ_GROUP_IOSCHED blkcg_deactivate_policy(q, &blkcg_policy_cfq); #else kfree(cfqd->root_group); #endif kfree(cfqd); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro3839.18%215.38%
Jens Axboe2929.90%538.46%
Tejun Heo1919.59%323.08%
Vivek Goyal1111.34%323.08%
Total97100.00%13100.00%


static int cfq_init_queue(struct request_queue *q, struct elevator_type *e) { struct cfq_data *cfqd; struct blkcg_gq *blkg __maybe_unused; int i, ret; struct elevator_queue *eq; eq = elevator_alloc(q, e); if (!eq) return -ENOMEM; cfqd = kzalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node); if (!cfqd) { kobject_put(&eq->kobj); return -ENOMEM; } eq->elevator_data = cfqd; cfqd->queue = q; spin_lock_irq(q->queue_lock); q->elevator = eq; spin_unlock_irq(q->queue_lock); /* Init root service tree */ cfqd->grp_service_tree = CFQ_RB_ROOT; /* Init root group and prefer root group over other groups by default */ #ifdef CONFIG_CFQ_GROUP_IOSCHED ret = blkcg_activate_policy(q, &blkcg_policy_cfq); if (ret) goto out_free; cfqd->root_group = blkg_to_cfqg(q->root_blkg); #else ret = -ENOMEM; cfqd->root_group = kzalloc_node(sizeof(*cfqd->root_group), GFP_KERNEL, cfqd->queue->node); if (!cfqd->root_group) goto out_free; cfq_init_cfqg_base(cfqd->root_group); cfqd->root_group->weight = 2 * CFQ_WEIGHT_LEGACY_DFL; cfqd->root_group->leaf_weight = 2 * CFQ_WEIGHT_LEGACY_DFL; #endif /* * Not strictly needed (since RB_ROOT just clears the node and we * zeroed cfqd on alloc), but better be safe in case someone decides * to add magic to the rb code */ for (i = 0; i < CFQ_PRIO_LISTS; i++) cfqd->prio_trees[i] = RB_ROOT; /* * Our fallback cfqq if cfq_get_queue() runs into OOM issues. * Grab a permanent reference to it, so that the normal code flow * will not attempt to free it. oom_cfqq is linked to root_group * but shouldn't hold a reference as it'll never be unlinked. Lose * the reference from linking right away. */ cfq_init_cfqq(cfqd, &cfqd->oom_cfqq, 1, 0); cfqd->oom_cfqq.ref++; spin_lock_irq(q->queue_lock); cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, cfqd->root_group); cfqg_put(cfqd->root_group); spin_unlock_irq(q->queue_lock); hrtimer_init(&cfqd->idle_slice_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); cfqd->idle_slice_timer.function = cfq_idle_slice_timer; INIT_WORK(&cfqd->unplug_work, cfq_kick_queue); cfqd->cfq_quantum = cfq_quantum; cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0]; cfqd->cfq_fifo_expire[1] = cfq_fifo_expire[1]; cfqd->cfq_back_max = cfq_back_max; cfqd->cfq_back_penalty = cfq_back_penalty; cfqd->cfq_slice[0] = cfq_slice_async; cfqd->cfq_slice[1] = cfq_slice_sync; cfqd->cfq_target_latency = cfq_target_latency; cfqd->cfq_slice_async_rq = cfq_slice_async_rq; cfqd->cfq_slice_idle = cfq_slice_idle; cfqd->cfq_group_idle = cfq_group_idle; cfqd->cfq_latency = 1; cfqd->hw_tag = -1; /* * we optimistically start assuming sync ops weren't delayed in last * second, in order to have larger depth for async operations. */ cfqd->last_delayed_sync = ktime_get_ns() - NSEC_PER_SEC; return 0; out_free: kfree(cfqd); kobject_put(&eq->kobj); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe19040.69%922.50%
Tejun Heo13128.05%1230.00%
Jianpeng Ma (马建朋)6714.35%12.50%
Vivek Goyal5311.35%922.50%
Aaron Carroll61.28%12.50%
Tao Ma61.28%12.50%
Jan Kara51.07%12.50%
Corrado Zoccolo40.86%37.50%
Jeff Moyer30.64%12.50%
David Shaohua Li10.21%12.50%
Joe Perches10.21%12.50%
Total467100.00%40100.00%


static void cfq_registered_queue(struct request_queue *q) { struct elevator_queue *e = q->elevator; struct cfq_data *cfqd = e->elevator_data; /* * Default to IOPS mode with no idling for SSDs */ if (blk_queue_nonrot(q)) cfqd->cfq_slice_idle = 0; wbt_disable_default(q); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe4389.58%150.00%
Jan Kara510.42%150.00%
Total48100.00%2100.00%

/* * sysfs parts below --> */
static ssize_t cfq_var_show(unsigned int var, char *page) { return sprintf(page, "%u\n", var); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe2395.83%150.00%
Masanari Iida14.17%150.00%
Total24100.00%2100.00%


static ssize_t cfq_var_store(unsigned int *var, const char *page, size_t count) { char *p = (char *) page; *var = simple_strtoul(p, &p, 10); return count; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe45100.00%1100.00%
Total45100.00%1100.00%

#define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ static ssize_t __FUNC(struct elevator_queue *e, char *page) \ { \ struct cfq_data *cfqd = e->elevator_data; \ u64 __data = __VAR; \ if (__CONV) \ __data = div_u64(__data, NSEC_PER_MSEC); \ return cfq_var_show(__data, (page)); \ } SHOW_FUNCTION(cfq_quantum_show, cfqd->cfq_quantum, 0); SHOW_FUNCTION(cfq_fifo_expire_sync_show, cfqd->cfq_fifo_expire[1], 1); SHOW_FUNCTION(cfq_fifo_expire_async_show, cfqd->cfq_fifo_expire[0], 1); SHOW_FUNCTION(cfq_back_seek_max_show, cfqd->cfq_back_max, 0); SHOW_FUNCTION(cfq_back_seek_penalty_show, cfqd->cfq_back_penalty, 0); SHOW_FUNCTION(cfq_slice_idle_show, cfqd->cfq_slice_idle, 1); SHOW_FUNCTION(cfq_group_idle_show, cfqd->cfq_group_idle, 1); SHOW_FUNCTION(cfq_slice_sync_show, cfqd->cfq_slice[1], 1); SHOW_FUNCTION(cfq_slice_async_show, cfqd->cfq_slice[0], 1); SHOW_FUNCTION(cfq_slice_async_rq_show, cfqd->cfq_slice_async_rq, 0); SHOW_FUNCTION(cfq_low_latency_show, cfqd->cfq_latency, 0); SHOW_FUNCTION(cfq_target_latency_show, cfqd->cfq_target_latency, 1); #undef SHOW_FUNCTION #define USEC_SHOW_FUNCTION(__FUNC, __VAR) \ static ssize_t __FUNC(struct elevator_queue *e, char *page) \ { \ struct cfq_data *cfqd = e->elevator_data; \ u64 __data = __VAR; \ __data = div_u64(__data, NSEC_PER_USEC); \ return cfq_var_show(__data, (page)); \ } USEC_SHOW_FUNCTION(cfq_slice_idle_us_show, cfqd->cfq_slice_idle); USEC_SHOW_FUNCTION(cfq_group_idle_us_show, cfqd->cfq_group_idle); USEC_SHOW_FUNCTION(cfq_slice_sync_us_show, cfqd->cfq_slice[1]); USEC_SHOW_FUNCTION(cfq_slice_async_us_show, cfqd->cfq_slice[0]); USEC_SHOW_FUNCTION(cfq_target_latency_us_show, cfqd->cfq_target_latency); #undef USEC_SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count) \ { \ struct cfq_data *cfqd = e->elevator_data; \ unsigned int __data; \ int ret = cfq_var_store(&__data, (page), count); \ if (__data < (MIN)) \ __data = (MIN); \ else if (__data > (MAX)) \ __data = (MAX); \ if (__CONV) \ *(__PTR) = (u64)__data * NSEC_PER_MSEC; \ else \ *(__PTR) = __data; \ return ret; \ } STORE_FUNCTION(cfq_quantum_store, &cfqd->cfq_quantum, 1, UINT_MAX, 0); STORE_FUNCTION(cfq_fifo_expire_sync_store, &cfqd->cfq_fifo_expire[1], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_fifo_expire_async_store, &cfqd->cfq_fifo_expire[0], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_back_seek_max_store, &cfqd->cfq_back_max, 0, UINT_MAX, 0); STORE_FUNCTION(cfq_back_seek_penalty_store, &cfqd->cfq_back_penalty, 1, UINT_MAX, 0); STORE_FUNCTION(cfq_slice_idle_store, &cfqd->cfq_slice_idle, 0, UINT_MAX, 1); STORE_FUNCTION(cfq_group_idle_store, &cfqd->cfq_group_idle, 0, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_sync_store, &cfqd->cfq_slice[1], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_async_store, &cfqd->cfq_slice[0], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_async_rq_store, &cfqd->cfq_slice_async_rq, 1, UINT_MAX, 0); STORE_FUNCTION(cfq_low_latency_store, &cfqd->cfq_latency, 0, 1, 0); STORE_FUNCTION(cfq_target_latency_store, &cfqd->cfq_target_latency, 1, UINT_MAX, 1); #undef STORE_FUNCTION #define USEC_STORE_FUNCTION(__FUNC, __PTR, MIN, MAX) \ static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count) \ { \ struct cfq_data *cfqd = e->elevator_data; \ unsigned int __data; \ int ret = cfq_var_store(&__data, (page), count); \ if (__data < (MIN)) \ __data = (MIN); \ else if (__data > (MAX)) \ __data = (MAX); \ *(__PTR) = (u64)__data * NSEC_PER_USEC; \ return ret; \ } USEC_STORE_FUNCTION(cfq_slice_idle_us_store, &cfqd->cfq_slice_idle, 0, UINT_MAX); USEC_STORE_FUNCTION(cfq_group_idle_us_store, &cfqd->cfq_group_idle, 0, UINT_MAX); USEC_STORE_FUNCTION(cfq_slice_sync_us_store, &cfqd->cfq_slice[1], 1, UINT_MAX); USEC_STORE_FUNCTION(cfq_slice_async_us_store, &cfqd->cfq_slice[0], 1, UINT_MAX); USEC_STORE_FUNCTION(cfq_target_latency_us_store, &cfqd->cfq_target_latency, 1, UINT_MAX); #undef USEC_STORE_FUNCTION #define CFQ_ATTR(name) \ __ATTR(name, S_IRUGO|S_IWUSR, cfq_##name##_show, cfq_##name##_store) static struct elv_fs_entry cfq_attrs[] = { CFQ_ATTR(quantum), CFQ_ATTR(fifo_expire_sync), CFQ_ATTR(fifo_expire_async), CFQ_ATTR(back_seek_max), CFQ_ATTR(back_seek_penalty), CFQ_ATTR(slice_sync), CFQ_ATTR(slice_sync_us), CFQ_ATTR(slice_async), CFQ_ATTR(slice_async_us), CFQ_ATTR(slice_async_rq), CFQ_ATTR(slice_idle), CFQ_ATTR(slice_idle_us), CFQ_ATTR(group_idle), CFQ_ATTR(group_idle_us), CFQ_ATTR(low_latency), CFQ_ATTR(target_latency), CFQ_ATTR(target_latency_us), __ATTR_NULL }; static struct elevator_type iosched_cfq = { .ops.sq = { .elevator_merge_fn = cfq_merge, .elevator_merged_fn = cfq_merged_request, .elevator_merge_req_fn = cfq_merged_requests, .elevator_allow_bio_merge_fn = cfq_allow_bio_merge, .elevator_allow_rq_merge_fn = cfq_allow_rq_merge, .elevator_bio_merged_fn = cfq_bio_merged, .elevator_dispatch_fn = cfq_dispatch_requests, .elevator_add_req_fn = cfq_insert_request, .elevator_activate_req_fn = cfq_activate_request, .elevator_deactivate_req_fn = cfq_deactivate_request, .elevator_completed_req_fn = cfq_completed_request, .elevator_former_req_fn = elv_rb_former_request, .elevator_latter_req_fn = elv_rb_latter_request, .elevator_init_icq_fn = cfq_init_icq, .elevator_exit_icq_fn = cfq_exit_icq, .elevator_set_req_fn = cfq_set_request, .elevator_put_req_fn = cfq_put_request, .elevator_may_queue_fn = cfq_may_queue, .elevator_init_fn = cfq_init_queue, .elevator_exit_fn = cfq_exit_queue, .elevator_registered_fn = cfq_registered_queue, }, .icq_size = sizeof(struct cfq_io_cq), .icq_align = __alignof__(struct cfq_io_cq), .elevator_attrs = cfq_attrs, .elevator_name = "cfq", .elevator_owner = THIS_MODULE, }; #ifdef CONFIG_CFQ_GROUP_IOSCHED static struct blkcg_policy blkcg_policy_cfq = { .dfl_cftypes = cfq_blkcg_files, .legacy_cftypes = cfq_blkcg_legacy_files, .cpd_alloc_fn = cfq_cpd_alloc, .cpd_init_fn = cfq_cpd_init, .cpd_free_fn = cfq_cpd_free, .cpd_bind_fn = cfq_cpd_bind, .pd_alloc_fn = cfq_pd_alloc, .pd_init_fn = cfq_pd_init, .pd_offline_fn = cfq_pd_offline, .pd_free_fn = cfq_pd_free, .pd_reset_stats_fn = cfq_pd_reset_stats, }; #endif
static int __init cfq_init(void) { int ret; #ifdef CONFIG_CFQ_GROUP_IOSCHED ret = blkcg_policy_register(&blkcg_policy_cfq); if (ret) return ret; #else cfq_group_idle = 0; #endif ret = -ENOMEM; cfq_pool = KMEM_CACHE(cfq_queue, 0); if (!cfq_pool) goto err_pol_unreg; ret = elv_register(&iosched_cfq); if (ret) goto err_free_pool; return 0; err_free_pool: kmem_cache_destroy(cfq_pool); err_pol_unreg: #ifdef CONFIG_CFQ_GROUP_IOSCHED blkcg_policy_unregister(&blkcg_policy_cfq); #endif return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Tejun Heo7473.27%555.56%
Jens Axboe1817.82%111.11%
Vivek Goyal76.93%222.22%
Andries E. Brouwer21.98%111.11%
Total101100.00%9100.00%


static void __exit cfq_exit(void) { #ifdef CONFIG_CFQ_GROUP_IOSCHED blkcg_policy_unregister(&blkcg_policy_cfq); #endif elv_unregister(&iosched_cfq); kmem_cache_destroy(cfq_pool); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe1445.16%337.50%
Tejun Heo1135.48%337.50%
Vivek Goyal412.90%112.50%
Christoph Hellwig26.45%112.50%
Total31100.00%8100.00%

module_init(cfq_init); module_exit(cfq_exit); MODULE_AUTHOR("Jens Axboe"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Completely Fair Queueing IO scheduler");

Overall Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe655632.25%10828.57%
Tejun Heo596729.35%9124.07%
Vivek Goyal248012.20%4211.11%
Corrado Zoccolo11165.49%184.76%
Jeff Moyer10054.94%112.91%
David Shaohua Li8023.94%215.56%
Andrew Morton3851.89%20.53%
Vasily Tarasov2501.23%20.53%
Divyesh Shah2311.14%112.91%
Justin TerAvest2121.04%41.06%
Jan Kara1910.94%92.38%
Arianna Avanzini1800.89%10.26%
Al Viro1670.82%92.38%
Peter Zijlstra1000.49%10.26%
Aaron Carroll990.49%10.26%
Christoph Hellwig860.42%61.59%
Jianpeng Ma (马建朋)670.33%10.26%
Andreas Mohr550.27%10.26%
Glauber de Oliveira Costa460.23%10.26%
Hou Tao420.21%10.26%
Tao Ma420.21%10.26%
Tahsin Erdogan410.20%10.26%
Gui Jianfeng360.18%51.32%
Toshiaki Makita310.15%20.53%
Konstantin Khlebnikov220.11%10.26%
David Howells210.10%10.26%
Michael Christie200.10%20.53%
Nikanth Karthikesan90.04%20.53%
Shaohua Li70.03%10.26%
Alexander Potapenko70.03%10.26%
Mike Snitzer60.03%10.26%
Arjan van de Ven60.03%10.26%
SF Markus Elfring60.03%10.26%
Richard Kennedy50.02%10.26%
Namhyung Kim50.02%20.53%
Kent Overstreet40.02%10.26%
Fabio Checconi30.01%10.26%
Anatol Pomozov30.01%10.26%
Shan Wei30.01%10.26%
Ingo Molnar30.01%10.26%
Christoph Lameter20.01%10.26%
Randy Dunlap20.01%10.26%
Oleg Nesterov20.01%10.26%
Andries E. Brouwer20.01%10.26%
Kyungmin Park10.00%10.26%
Kirill A. Shutemov10.00%10.26%
Joe Perches10.00%10.26%
Masanari Iida10.00%10.26%
Lucas De Marchi10.00%10.26%
Total20330100.00%378100.00%
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