Re: [RFC PATCH v2 02/10] mm/damon/core: allow quota goals set zero effective size quota

SeongJae Park
2026-03-04T14:51:42Z

On Wed, 4 Mar 2026 13:18:16 +0300 Gutierrez Asier <gutierrez.asier@huawei-partners.com> wrote:

>
>
> On 3/4/2026 7:41 AM, SeongJae Park wrote:
>
> I find the name of this function confusing. The function doesn't
> actually set anything. Maybe better damos_quota_is_set()
> > +/*
> > + * damos_quota_set() - Return if the given quota is actually set.
> > + * @quota: The quota to check.
> > + *
> > + * Returns true if the quota is set, false otherwise.
> > + */
> > +static bool damos_quota_set(struct damos_quota *quota)
> > +{
> > + return quota->esz || quota->sz || quota->ms ||
> > + !damos_quota_goals_empty(quota);
> > +}
> > +

Thank you for the nice suggestion, I agree your points and like the suggested
name!

Andrew, if you pick this patch to mm-new for more reviews, could you please add
below attaching fixup together?

Thanks,
SJ

[...]
=== >8 ===
From 9599524cc5e5bbe8263c847b6f20f0aa919b3853 Mon Sep 17 00:00:00 2001
From: SeongJae Park <sj@kernel.org>
Date: Wed, 4 Mar 2026 06:46:55 -0800
Subject: [PATCH] mm/damon/core: rename damos_quota_set() to
damos_quota_is_set()

damos_quota_set() can be confused as a sort of setter function. Rename.

Suggested-by: Gutierrez Asier <gutierrez.asier@huawei-partners.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
---
mm/damon/core.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index d657b87dd99e8..c58430a4cd6ef 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1788,12 +1788,12 @@ static bool __damos_valid_target(struct damon_region *r, struct damos *s)
}

/*
- * damos_quota_set() - Return if the given quota is actually set.
+ * damos_quota_is_set() - Return if the given quota is actually set.
* @quota: The quota to check.
*
* Returns true if the quota is set, false otherwise.
*/
-static bool damos_quota_set(struct damos_quota *quota)
+static bool damos_quota_is_set(struct damos_quota *quota)
{
return quota->esz || quota->sz || quota->ms ||
!damos_quota_goals_empty(quota);
@@ -1804,7 +1804,7 @@ static bool damos_valid_target(struct damon_ctx *c, struct damon_region *r,
{
bool ret = __damos_valid_target(r, s);

- if (!ret || !damos_quota_set(&s->quota) || !c->ops.get_scheme_score)
+ if (!ret || !damos_quota_is_set(&s->quota) || !c->ops.get_scheme_score)
return ret;

return c->ops.get_scheme_score(c, r, s) >= s->quota.min_score;
@@ -2074,7 +2074,7 @@ static void damos_apply_scheme(struct damon_ctx *c, struct damon_target *t,
}

if (c->ops.apply_scheme) {
- if (damos_quota_set(quota) &&
+ if (damos_quota_is_set(quota) &&
quota->charged_sz + sz > quota->esz) {
sz = ALIGN_DOWN(quota->esz - quota->charged_sz,
c->min_region_sz);
@@ -2094,7 +2094,7 @@ static void damos_apply_scheme(struct damon_ctx *c, struct damon_target *t,
quota->total_charged_ns += timespec64_to_ns(&end) -
timespec64_to_ns(&begin);
quota->charged_sz += sz;
- if (damos_quota_set(quota) &&
+ if (damos_quota_is_set(quota) &&
quota->charged_sz >= quota->esz) {
quota->charge_target_from = t;
quota->charge_addr_from = r->ar.end + 1;
@@ -2123,7 +2123,8 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
continue;

/* Check the quota */
- if (damos_quota_set(quota) && quota->charged_sz >= quota->esz)
+ if (damos_quota_is_set(quota) &&
+ quota->charged_sz >= quota->esz)
continue;

if (damos_skip_charged_region(t, r, s, c->min_region_sz))
@@ -2408,7 +2409,8 @@ static void damos_adjust_quota(struct damon_ctx *c, struct damos *s)
/* New charge window starts */
if (time_after_eq(jiffies, quota->charged_from +
msecs_to_jiffies(quota->reset_interval))) {
- if (damos_quota_set(quota) && quota->charged_sz >= quota->esz)
+ if (damos_quota_is_set(quota) &&
+ quota->charged_sz >= quota->esz)
s->stat.qt_exceeds++;
quota->total_charged_sz += quota->charged_sz;
quota->charged_from = jiffies;
--
2.47.3