From: SeongJae Park sj@kernel.org
mainline inclusion from mainline-v5.17-rc1 commit 6268eac34ca30af7f6313504d556ec7fcd295621 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4RTX9
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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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 sj@kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org (cherry picked from commit 6268eac34ca30af7f6313504d556ec7fcd295621) Signed-off-by: Yue Zou zouyue3@huawei.com Reviewed-by: Kefeng Wangwangkefeng.wang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- 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 e0ad3d9aaeed..af648388e759 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -198,12 +198,14 @@ 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;