On 2023/5/27 9:46, SeongJae Park wrote:
Hi Kefeng,
On Sat, 27 May 2023 09:15:01 +0800 Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
[...]
Nice and effective fix! Nevertheless, I think aggregation interval smaller
than sample interval is just a wrong input. How about adding the check in
damon_set_attrs()'s already existing attributes validation, like below?
Yes, move the check into damon_set_attrs() is better
Thank you for this kind comment!
, and it seems that
we could move all the check into it, and drop the old_attrs check in
damon_update_monitoring_results(), what's you option?
diff --git a/mm/damon/core.c b/mm/damon/core.c
index d9ef62047bf5..1647f7f1f708 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -523,12 +523,6 @@ static void damon_update_monitoring_results(struct
damon_ctx *ctx,
struct damon_target *t;
struct damon_region *r;
- /* if any interval is zero, simply forgive conversion */
- if (!old_attrs->sample_interval || !old_attrs->aggr_interval ||
- !new_attrs->sample_interval ||
- !new_attrs->aggr_interval)
- return;
-
damon_for_each_target(t, ctx)
damon_for_each_region(r, t)
damon_update_monitoring_result(
@@ -551,6 +545,10 @@ int damon_set_attrs(struct damon_ctx *ctx, struct
damon_attrs *attrs)
return -EINVAL;
if (attrs->min_nr_regions > attrs->max_nr_regions)
return -EINVAL;
+ if (attrs->sample_interval > attrs->aggr_interval)
+ return -EINVAL;
+ if (!attrs->sample_interval || !attrs->aggr_interval)
+ return -EINVAL;
In my humble opinion, the validation for monitoring results and for general
monitoring could be different. For example, zero aggreation/sampling intervals
might make sense for fixed granularity working set size monitoring. Hence, I'd
prefer keeping those checks in the damon_update_monitoring_results().
ok, will keep that, I check the damon_set_attrs() called by
lru_sort/reclaim monitor and sysfs/dbgfs, the above changes should be
ok, maybe missing something, the working set size monitoring is not
public for now?
Thanks,
SJ
[...]
