From f755f1a2bc6160162398694aff1281a2fe92bd10 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Fri, 14 Jan 2022 14:10:20 -0800 Subject: [PATCH] UPSTREAM: mm/damon/schemes: account how many times quota limit has exceeded If the time/space quotas of a given DAMON-based operation scheme is too small, the scheme could show unexpectedly slow progress. However, there is no good way to notice the case in runtime. This commit extends the DAMOS stat to provide how many times the quota limits exceeded so that the users can easily notice the case and tune the scheme. Link: https://lkml.kernel.org/r/20211210150016.35349-3-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds (cherry picked from commit 6268eac34ca30af7f6313504d556ec7fcd295621) Bug: 228223814 Signed-off-by: Hailong Tu Change-Id: I36184dc51917810c81ac8d576b144e33a4454dc1 --- include/linux/damon.h | 2 ++ mm/damon/core.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/include/linux/damon.h b/include/linux/damon.h index 59fcb5f89594..9dbb2210a286 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -195,12 +195,14 @@ struct damos_watermarks { * @sz_tried: Total size of regions that the scheme is tried to be applied. * @nr_applied: Total number of regions that the scheme is applied. * @sz_applied: Total size of regions that the scheme is applied. + * @qt_exceeds: Total number of times the quota of the scheme has exceeded. */ struct damos_stat { unsigned long nr_tried; unsigned long sz_tried; unsigned long nr_applied; unsigned long sz_applied; + unsigned long qt_exceeds; }; /** diff --git a/mm/damon/core.c b/mm/damon/core.c index d745bf28509f..d5120b326e1b 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -693,6 +693,8 @@ static void kdamond_apply_schemes(struct damon_ctx *c) if (time_after_eq(jiffies, quota->charged_from + msecs_to_jiffies( quota->reset_interval))) { + if (quota->esz && quota->charged_sz >= quota->esz) + s->stat.qt_exceeds++; quota->total_charged_sz += quota->charged_sz; quota->charged_from = jiffies; quota->charged_sz = 0;