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(). Thanks, SJ [...]
