cregit-Linux how code gets into the kernel

Release 4.7 kernel/sched/cpuacct.c

Directory: kernel/sched
#include <linux/cgroup.h>
#include <linux/slab.h>
#include <linux/percpu.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/seq_file.h>
#include <linux/rcupdate.h>
#include <linux/kernel_stat.h>
#include <linux/err.h>

#include "sched.h"

/*
 * CPU accounting code for task groups.
 *
 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
 * (balbir@in.ibm.com).
 */

/* Time spent by the tasks of the cpu accounting group executing in ... */

enum cpuacct_stat_index {
	
CPUACCT_STAT_USER,	/* ... user mode */
	
CPUACCT_STAT_SYSTEM,	/* ... kernel mode */

	
CPUACCT_STAT_NSTATS,
};


enum cpuacct_usage_index {
	
CPUACCT_USAGE_USER,	/* ... user mode */
	
CPUACCT_USAGE_SYSTEM,	/* ... kernel mode */

	
CPUACCT_USAGE_NRUSAGE,
};


struct cpuacct_usage {
	
u64	usages[CPUACCT_USAGE_NRUSAGE];
};

/* track cpu usage of a group of tasks and its child groups */

struct cpuacct {
	
struct cgroup_subsys_state css;
	/* cpuusage holds pointer to a u64-type object on every cpu */
	
struct cpuacct_usage __percpu *cpuusage;
	
struct kernel_cpustat __percpu *cpustat;
};


static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css) { return css ? container_of(css, struct cpuacct, css) : NULL; }

Contributors

PersonTokensPropCommitsCommitProp
tejun heotejun heo29100.00%1100.00%
Total29100.00%1100.00%

/* return cpu accounting group to which this task belongs */
static inline struct cpuacct *task_ca(struct task_struct *tsk) { return css_ca(task_css(tsk, cpuacct_cgrp_id)); }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan2288.00%125.00%
tejun heotejun heo312.00%375.00%
Total25100.00%4100.00%


static inline struct cpuacct *parent_ca(struct cpuacct *ca) { return css_ca(ca->css.parent); }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan2083.33%133.33%
tejun heotejun heo416.67%266.67%
Total24100.00%3100.00%

static DEFINE_PER_CPU(struct cpuacct_usage, root_cpuacct_cpuusage); static struct cpuacct root_cpuacct = { .cpustat = &kernel_cpustat, .cpuusage = &root_cpuacct_cpuusage, }; /* create a new cpu accounting group */
static struct cgroup_subsys_state * cpuacct_css_alloc(struct cgroup_subsys_state *parent_css) { struct cpuacct *ca; if (!parent_css) return &root_cpuacct.css; ca = kzalloc(sizeof(*ca), GFP_KERNEL); if (!ca) goto out; ca->cpuusage = alloc_percpu(struct cpuacct_usage); if (!ca->cpuusage) goto out_free_ca; ca->cpustat = alloc_percpu(struct kernel_cpustat); if (!ca->cpustat) goto out_free_cpuusage; return &ca->css; out_free_cpuusage: free_percpu(ca->cpuusage); out_free_ca: kfree(ca); out: return ERR_PTR(-ENOMEM); }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan11695.87%133.33%
tejun heotejun heo32.48%133.33%
dongsheng yangdongsheng yang21.65%133.33%
Total121100.00%3100.00%

/* destroy an existing cpu accounting group */
static void cpuacct_css_free(struct cgroup_subsys_state *css) { struct cpuacct *ca = css_ca(css); free_percpu(ca->cpustat); free_percpu(ca->cpuusage); kfree(ca); }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan3690.00%150.00%
tejun heotejun heo410.00%150.00%
Total40100.00%2100.00%


static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu, enum cpuacct_usage_index index) { struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); u64 data; /* * We allow index == CPUACCT_USAGE_NRUSAGE here to read * the sum of suages. */ BUG_ON(index > CPUACCT_USAGE_NRUSAGE); #ifndef CONFIG_64BIT /* * Take rq->lock to make 64-bit read safe on 32-bit platforms. */ raw_spin_lock_irq(&cpu_rq(cpu)->lock); #endif if (index == CPUACCT_USAGE_NRUSAGE) { int i = 0; data = 0; for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++) data += cpuusage->usages[i]; } else { data = cpuusage->usages[index]; } #ifndef CONFIG_64BIT raw_spin_unlock_irq(&cpu_rq(cpu)->lock); #endif return data; }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang6650.77%150.00%
li zefanli zefan6449.23%150.00%
Total130100.00%2100.00%


static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val) { struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); int i; #ifndef CONFIG_64BIT /* * Take rq->lock to make 64-bit write safe on 32-bit platforms. */ raw_spin_lock_irq(&cpu_rq(cpu)->lock); #endif for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++) cpuusage->usages[i] = val; #ifndef CONFIG_64BIT raw_spin_unlock_irq(&cpu_rq(cpu)->lock); #endif }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan6168.54%150.00%
dongsheng yangdongsheng yang2831.46%150.00%
Total89100.00%2100.00%

/* return total cpu usage (in nanoseconds) of a group */
static u64 __cpuusage_read(struct cgroup_subsys_state *css, enum cpuacct_usage_index index) { struct cpuacct *ca = css_ca(css); u64 totalcpuusage = 0; int i; for_each_possible_cpu(i) totalcpuusage += cpuacct_cpuusage_read(ca, i, index); return totalcpuusage; }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan4078.43%125.00%
dongsheng yangdongsheng yang611.76%125.00%
tejun heotejun heo47.84%125.00%
zhao leizhao lei11.96%125.00%
Total51100.00%4100.00%


static u64 cpuusage_user_read(struct cgroup_subsys_state *css, struct cftype *cft) { return __cpuusage_read(css, CPUACCT_USAGE_USER); }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang24100.00%1100.00%
Total24100.00%1100.00%


static u64 cpuusage_sys_read(struct cgroup_subsys_state *css, struct cftype *cft) { return __cpuusage_read(css, CPUACCT_USAGE_SYSTEM); }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang24100.00%1100.00%
Total24100.00%1100.00%


static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft) { return __cpuusage_read(css, CPUACCT_USAGE_NRUSAGE); }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang24100.00%1100.00%
Total24100.00%1100.00%


static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft, u64 val) { struct cpuacct *ca = css_ca(css); int cpu; /* * Only allow '0' here to do a reset. */ if (val) return -EINVAL; for_each_possible_cpu(cpu) cpuacct_cpuusage_write(ca, cpu, 0); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan4273.68%120.00%
dongsheng yangdongsheng yang915.79%240.00%
tejun heotejun heo58.77%120.00%
zhao leizhao lei11.75%120.00%
Total57100.00%5100.00%


static int __cpuacct_percpu_seq_show(struct seq_file *m, enum cpuacct_usage_index index) { struct cpuacct *ca = css_ca(seq_css(m)); u64 percpu; int i; for_each_possible_cpu(i) { percpu = cpuacct_cpuusage_read(ca, i, index); seq_printf(m, "%llu ", (unsigned long long) percpu); } seq_printf(m, "\n"); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan6282.67%120.00%
tejun heotejun heo68.00%240.00%
dongsheng yangdongsheng yang68.00%120.00%
zhao leizhao lei11.33%120.00%
Total75100.00%5100.00%


static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V) { return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_USER); }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang23100.00%1100.00%
Total23100.00%1100.00%


static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V) { return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_SYSTEM); }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang23100.00%1100.00%
Total23100.00%1100.00%


static int cpuacct_percpu_seq_show(struct seq_file *m, void *V) { return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_NRUSAGE); }

Contributors

PersonTokensPropCommitsCommitProp
dongsheng yangdongsheng yang23100.00%1100.00%
Total23100.00%1100.00%

static const char * const cpuacct_stat_desc[] = { [CPUACCT_STAT_USER] = "user", [CPUACCT_STAT_SYSTEM] = "system", };
static int cpuacct_stats_show(struct seq_file *sf, void *v) { struct cpuacct *ca = css_ca(seq_css(sf)); int cpu; s64 val = 0; for_each_possible_cpu(cpu) { struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); val += kcpustat->cpustat[CPUTIME_USER]; val += kcpustat->cpustat[CPUTIME_NICE]; } val = cputime64_to_clock_t(val); seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val); val = 0; for_each_possible_cpu(cpu) { struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); val += kcpustat->cpustat[CPUTIME_SYSTEM]; val += kcpustat->cpustat[CPUTIME_IRQ]; val += kcpustat->cpustat[CPUTIME_SOFTIRQ]; } val = cputime64_to_clock_t(val); seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan14987.65%120.00%
tejun heotejun heo1911.18%360.00%
zhao leizhao lei21.18%120.00%
Total170100.00%5100.00%

static struct cftype files[] = { { .name = "usage", .read_u64 = cpuusage_read, .write_u64 = cpuusage_write, }, { .name = "usage_user", .read_u64 = cpuusage_user_read, }, { .name = "usage_sys", .read_u64 = cpuusage_sys_read, }, { .name = "usage_percpu", .seq_show = cpuacct_percpu_seq_show, }, { .name = "usage_percpu_user", .seq_show = cpuacct_percpu_user_seq_show, }, { .name = "usage_percpu_sys", .seq_show = cpuacct_percpu_sys_seq_show, }, { .name = "stat", .seq_show = cpuacct_stats_show, }, { } /* terminate */ }; /* * charge this task's execution time to its accounting group. * * called with rq->lock held. */
void cpuacct_charge(struct task_struct *tsk, u64 cputime) { struct cpuacct *ca; int index = CPUACCT_USAGE_SYSTEM; struct pt_regs *regs = task_pt_regs(tsk); if (regs && user_mode(regs)) index = CPUACCT_USAGE_USER; rcu_read_lock(); for (ca = task_ca(tsk); ca; ca = parent_ca(ca)) this_cpu_ptr(ca->cpuusage)->usages[index] += cputime; rcu_read_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan3845.24%350.00%
dongsheng yangdongsheng yang1821.43%116.67%
anton blanchardanton blanchard1517.86%116.67%
zhao leizhao lei1315.48%116.67%
Total84100.00%6100.00%

/* * Add user/system time to cpuacct. * * Note: it's the caller that updates the account of the root cgroup. */
void cpuacct_account_field(struct task_struct *tsk, int index, u64 val) { struct cpuacct *ca; rcu_read_lock(); for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca)) this_cpu_ptr(ca->cpustat)->cpustat[index] += val; rcu_read_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan5080.65%266.67%
zhao leizhao lei1219.35%133.33%
Total62100.00%3100.00%

struct cgroup_subsys cpuacct_cgrp_subsys = { .css_alloc = cpuacct_css_alloc, .css_free = cpuacct_css_free, .legacy_cftypes = files, .early_init = true, };

Overall Contributors

PersonTokensPropCommitsCommitProp
li zefanli zefan88864.82%729.17%
dongsheng yangdongsheng yang35125.62%28.33%
tejun heotejun heo836.06%1145.83%
zhao leizhao lei302.19%28.33%
anton blanchardanton blanchard151.09%14.17%
ingo molnaringo molnar30.22%14.17%
Total1370100.00%24100.00%
Directory: kernel/sched
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}