Commit 9667a23d authored by Thomas Gleixner's avatar Thomas Gleixner Committed by John Stultz
Browse files

delayacct: Make accounting nanosecond based 



Kill the timespec juggling and calculate with plain nanoseconds.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
parent ccbf62d8

include/linux/sched.h

+2 −2
Original line number Diff line number Diff line
@@ -813,7 +813,7 @@ struct task_delay_info { 
	 * associated with the operation is added to XXX_delay.

	 * XXX_delay contains the accumulated delay time in nanoseconds.

	 */

	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */

	u64 blkio_start;	/* Shared by blkio, swapin */

	u64 blkio_delay;	/* wait for sync block io completion */

	u64 swapin_delay;	/* wait for swapin block io completion */

	u32 blkio_count;	/* total count of the number of sync block */
@@ -821,7 +821,7 @@ struct task_delay_info { 
	u32 swapin_count;	/* total count of the number of swapin block */

				/* io operations performed */



	struct timespec freepages_start, freepages_end;

	u64 freepages_start;

	u64 freepages_delay;	/* wait for memory reclaim */

	u32 freepages_count;	/* total count of memory reclaim */

};

kernel/delayacct.c

+12 −22
Original line number Diff line number Diff line
@@ -46,32 +46,25 @@ void __delayacct_tsk_init(struct task_struct *tsk) 
}



/*

 * Finish delay accounting for a statistic using

 * its timestamps (@start, @end), accumalator (@total) and @count

 * Finish delay accounting for a statistic using its timestamps (@start),

 * accumalator (@total) and @count

 */



static void delayacct_end(struct timespec *start, struct timespec *end,

				u64 *total, u32 *count)

static void delayacct_end(u64 *start, u64 *total, u32 *count)

{

	struct timespec ts;

	s64 ns;

	s64 ns = ktime_get_ns() - *start;

	unsigned long flags;



	ktime_get_ts(end);

	ts = timespec_sub(*end, *start);

	ns = timespec_to_ns(&ts);

	if (ns < 0)

		return;



	if (ns > 0) {

		spin_lock_irqsave(&current->delays->lock, flags);

		*total += ns;

		(*count)++;

		spin_unlock_irqrestore(&current->delays->lock, flags);

	}

}



void __delayacct_blkio_start(void)

{

	ktime_get_ts(&current->delays->blkio_start);

	current->delays->blkio_start = ktime_get_ns();

}



void __delayacct_blkio_end(void)
@@ -79,12 +72,10 @@ void __delayacct_blkio_end(void) 
	if (current->delays->flags & DELAYACCT_PF_SWAPIN)

		/* Swapin block I/O */

		delayacct_end(&current->delays->blkio_start,

			&current->delays->blkio_end,

			&current->delays->swapin_delay,

			&current->delays->swapin_count);

	else	/* Other block I/O */

		delayacct_end(&current->delays->blkio_start,

			&current->delays->blkio_end,

			&current->delays->blkio_delay,

			&current->delays->blkio_count);

}
@@ -159,13 +150,12 @@ __u64 __delayacct_blkio_ticks(struct task_struct *tsk) 


void __delayacct_freepages_start(void)

{

	ktime_get_ts(&current->delays->freepages_start);

	current->delays->freepages_start = ktime_get_ns();

}



void __delayacct_freepages_end(void)

{

	delayacct_end(&current->delays->freepages_start,

			&current->delays->freepages_end,

			&current->delays->freepages_delay,

			&current->delays->freepages_count);

}