Release 4.12 include/linux/ioprio.h
#ifndef IOPRIO_H
#define IOPRIO_H
#include <linux/sched.h>
#include <linux/iocontext.h>
/*
* Gives us 8 prio classes with 13-bits of data for each class
*/
#define IOPRIO_CLASS_SHIFT (13)
#define IOPRIO_PRIO_MASK ((1UL << IOPRIO_CLASS_SHIFT) - 1)
#define IOPRIO_PRIO_CLASS(mask) ((mask) >> IOPRIO_CLASS_SHIFT)
#define IOPRIO_PRIO_DATA(mask) ((mask) & IOPRIO_PRIO_MASK)
#define IOPRIO_PRIO_VALUE(class, data) (((class) << IOPRIO_CLASS_SHIFT) | data)
#define ioprio_valid(mask) (IOPRIO_PRIO_CLASS((mask)) != IOPRIO_CLASS_NONE)
/*
* These are the io priority groups as implemented by CFQ. RT is the realtime
* class, it always gets premium service. BE is the best-effort scheduling
* class, the default for any process. IDLE is the idle scheduling class, it
* is only served when no one else is using the disk.
*/
enum {
IOPRIO_CLASS_NONE,
IOPRIO_CLASS_RT,
IOPRIO_CLASS_BE,
IOPRIO_CLASS_IDLE,
};
/*
* 8 best effort priority levels are supported
*/
#define IOPRIO_BE_NR (8)
enum {
IOPRIO_WHO_PROCESS = 1,
IOPRIO_WHO_PGRP,
IOPRIO_WHO_USER,
};
/*
* Fallback BE priority
*/
#define IOPRIO_NORM (4)
/*
* if process has set io priority explicitly, use that. if not, convert
* the cpu scheduler nice value to an io priority
*/
static inline int task_nice_ioprio(struct task_struct *task)
{
return (task_nice(task) + 20) / 5;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Jens Axboe | 24 | 100.00% | 1 | 100.00% |
Total | 24 | 100.00% | 1 | 100.00% |
/*
* This is for the case where the task hasn't asked for a specific IO class.
* Check for idle and rt task process, and return appropriate IO class.
*/
static inline int task_nice_ioclass(struct task_struct *task)
{
if (task->policy == SCHED_IDLE)
return IOPRIO_CLASS_IDLE;
else if (task->policy == SCHED_FIFO || task->policy == SCHED_RR)
return IOPRIO_CLASS_RT;
else
return IOPRIO_CLASS_BE;
}
Contributors
Person | Tokens | Prop | Commits | CommitProp |
Jens Axboe | 45 | 100.00% | 1 | 100.00% |
Total | 45 | 100.00% | 1 | 100.00% |
/*
* For inheritance, return the highest of the two given priorities
*/
extern int ioprio_best(unsigned short aprio, unsigned short bprio);
extern int set_task_ioprio(struct task_struct *task, int ioprio);
#endif
Overall Contributors
Person | Tokens | Prop | Commits | CommitProp |
Jens Axboe | 167 | 90.76% | 4 | 57.14% |
Theodore Y. Ts'o | 13 | 7.07% | 1 | 14.29% |
Oleg Nesterov | 2 | 1.09% | 1 | 14.29% |
Tejun Heo | 2 | 1.09% | 1 | 14.29% |
Total | 184 | 100.00% | 7 | 100.00% |
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