Commit 19fb518c authored by Dmitry Adamushko's avatar Dmitry Adamushko Committed by Ingo Molnar
Browse files

latencytop: optimize LT_BACKTRACEDEPTH loops a bit 



There is no need to loop any longer when 'same == 0'.

Signed-off-by: default avatarDmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 50df5d6a

kernel/latencytop.c

+17 −10
Original line number Diff line number Diff line
@@ -64,8 +64,8 @@ account_global_scheduler_latency(struct task_struct *tsk, struct latency_record 
		return;



	for (i = 0; i < MAXLR; i++) {

		int q;

		int same = 1;

		int q, same = 1;



		/* Nothing stored: */

		if (!latency_record[i].backtrace[0]) {

			if (firstnonnull > i)
@@ -73,12 +73,15 @@ account_global_scheduler_latency(struct task_struct *tsk, struct latency_record 
			continue;

		}

		for (q = 0 ; q < LT_BACKTRACEDEPTH ; q++) {

			if (latency_record[i].backtrace[q] !=

				lat->backtrace[q])

			unsigned long record = lat->backtrace[q];



			if (latency_record[i].backtrace[q] != record) {

				same = 0;

			if (same && lat->backtrace[q] == 0)

				break;

			if (same && lat->backtrace[q] == ULONG_MAX)

			}



			/* 0 and ULONG_MAX entries mean end of backtrace: */

			if (record == 0 || record == ULONG_MAX)

				break;

		}

		if (same) {
@@ -143,14 +146,18 @@ account_scheduler_latency(struct task_struct *tsk, int usecs, int inter) 
	for (i = 0; i < LT_SAVECOUNT ; i++) {

		struct latency_record *mylat;

		int same = 1;



		mylat = &tsk->latency_record[i];

		for (q = 0 ; q < LT_BACKTRACEDEPTH ; q++) {

			if (mylat->backtrace[q] !=

				lat.backtrace[q])

			unsigned long record = lat.backtrace[q];



			if (mylat->backtrace[q] != record) {

				same = 0;

			if (same && lat.backtrace[q] == 0)

				break;

			if (same && lat.backtrace[q] == ULONG_MAX)

			}



			/* 0 and ULONG_MAX entries mean end of backtrace: */

			if (record == 0 || record == ULONG_MAX)

				break;

		}

		if (same) {