mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-13 01:36:55 +07:00
sched/core: Separate out io_schedule_prepare() and io_schedule_finish()
Now that IO schedule accounting is done inside __schedule(), io_schedule() can be split into three steps - prep, schedule, and finish - where the schedule part doesn't need any special annotation. This allows marking a sleep as iowait by simply wrapping an existing blocking function with io_schedule_prepare() and io_schedule_finish(). Because task_struct->in_iowait is single bit, the caller of io_schedule_prepare() needs to record and the pass its state to io_schedule_finish() to be safe regarding nesting. While this isn't the prettiest, these functions are mostly gonna be used by core functions and we don't want to use more space for ->in_iowait. While at it, as it's simple to do now, reimplement io_schedule() without unnecessarily going through io_schedule_timeout(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adilger.kernel@dilger.ca Cc: jack@suse.com Cc: kernel-team@fb.com Cc: mingbo@fb.com Cc: tytso@mit.edu Link: http://lkml.kernel.org/r/1477673892-28940-3-git-send-email-tj@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
parent
e33a9bba85
commit
10ab56434f
@ -461,12 +461,10 @@ extern signed long schedule_timeout_idle(signed long timeout);
|
||||
asmlinkage void schedule(void);
|
||||
extern void schedule_preempt_disabled(void);
|
||||
|
||||
extern int __must_check io_schedule_prepare(void);
|
||||
extern void io_schedule_finish(int token);
|
||||
extern long io_schedule_timeout(long timeout);
|
||||
|
||||
static inline void io_schedule(void)
|
||||
{
|
||||
io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
|
||||
}
|
||||
extern void io_schedule(void);
|
||||
|
||||
void __noreturn do_task_dead(void);
|
||||
|
||||
|
@ -5128,25 +5128,48 @@ int __sched yield_to(struct task_struct *p, bool preempt)
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(yield_to);
|
||||
|
||||
int io_schedule_prepare(void)
|
||||
{
|
||||
int old_iowait = current->in_iowait;
|
||||
|
||||
current->in_iowait = 1;
|
||||
blk_schedule_flush_plug(current);
|
||||
|
||||
return old_iowait;
|
||||
}
|
||||
|
||||
void io_schedule_finish(int token)
|
||||
{
|
||||
current->in_iowait = token;
|
||||
}
|
||||
|
||||
/*
|
||||
* This task is about to go to sleep on IO. Increment rq->nr_iowait so
|
||||
* that process accounting knows that this is a task in IO wait state.
|
||||
*/
|
||||
long __sched io_schedule_timeout(long timeout)
|
||||
{
|
||||
int old_iowait = current->in_iowait;
|
||||
int token;
|
||||
long ret;
|
||||
|
||||
current->in_iowait = 1;
|
||||
blk_schedule_flush_plug(current);
|
||||
|
||||
token = io_schedule_prepare();
|
||||
ret = schedule_timeout(timeout);
|
||||
current->in_iowait = old_iowait;
|
||||
io_schedule_finish(token);
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(io_schedule_timeout);
|
||||
|
||||
void io_schedule(void)
|
||||
{
|
||||
int token;
|
||||
|
||||
token = io_schedule_prepare();
|
||||
schedule();
|
||||
io_schedule_finish(token);
|
||||
}
|
||||
EXPORT_SYMBOL(io_schedule);
|
||||
|
||||
/**
|
||||
* sys_sched_get_priority_max - return maximum RT priority.
|
||||
* @policy: scheduling class.
|
||||
|
Loading…
Reference in New Issue
Block a user