Re: [PATCH v2 1/7] mm/damon/api: introduce DAMOS_FILTER_TYPE_PROBE_HITS_WSUM

[SJ Park <sj@kernel.org>]

On Fri, 11 Sep 2026 06:55:03 -0700 SJ Park <sj@kernel.org> wrote:

> Update DAMON kernel API to introduce new DAMOS core filter type,
> PROBE_HITS_WSUM.  It will allow API callers to describe the DAMOS action
> target regions based on their probe_hits weighted sum.  For describing
> the filtering target weighted sum range, add two type-dependent union
> fields to damos_filter.
> 
> Signed-off-by: SJ Park <sj@kernel.org>
> ---
>  include/linux/damon.h | 20 ++++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/damon.h b/include/linux/damon.h
> index 16800b3dc379b..9e84bdeb5616d 100644
> --- a/include/linux/damon.h
> +++ b/include/linux/damon.h
> @@ -399,14 +399,15 @@ struct damos_stat {
>   * @DAMOS_FILTER_TYPE_UNMAPPED:	Unmapped pages.
>   * @DAMOS_FILTER_TYPE_ADDR:	Address range.
>   * @DAMOS_FILTER_TYPE_TARGET:	Data Access Monitoring target.
> + * @DAMOS_FILTER_TYPE_PROBE_HITS_WSUM:	probe_hits weighted sum range.
>   * @NR_DAMOS_FILTER_TYPES:	Number of filter types.
>   *
> - * All types except &DAMOS_FILTER_TYPE_ADDR and &DAMOS_FILTER_TYPE_TARGET
> - * are handled by the underlying &struct damon_operations as a part of scheme
> - * action trying, and therefore accounted as 'tried'.  In contrast,
> - * &DAMOS_FILTER_TYPE_ADDR and &DAMOS_FILTER_TYPE_TARGET filters are handled
> - * by the core layer before trying of the action, and therefore not accounted
> - * as 'tried'.
> + * All types except &DAMOS_FILTER_TYPE_ADDR, &DAMOS_FILTER_TYPE_TARGET and
> + * &DAMOS_FILTER_TYPE_PROBE_HITS_WSUM are handled by the underlying &struct
> + * damon_operations as a part of scheme action trying, and therefore accounted
> + * as 'tried'.  In contrast, &DAMOS_FILTER_TYPE_ADDR and
> + * &DAMOS_FILTER_TYPE_TARGET filters are handled by the core layer before
> + * trying of the action, and therefore not accounted as 'tried'.

Sashiko found [1] the second sentence is also better to be updated.  Reposting
this patch only for the trivial change feels too much to me.  Andrew, could you
please add attaching patch as a fixup?  Please let me know if you prefer
reposting the series.

[1] https://lore.kernel.org/20260911142049.97838-1-sj@kernel.org


Thanks,
SJ

[...]
=== >8 ===
From 8095628debba5ececa0664314ef4a3b777ef0fbf Mon Sep 17 00:00:00 2001
From: SJ Park <sj@kernel.org>
Date: Fri, 11 Sep 2026 07:20:01 -0700
Subject: [PATCH] mm/damon/api: clarify DAMOS_FILTER_TYPE_PROBE_HITS_WSUM
 behavior

Clarify it's behavior.

Signed-off-by: SJ Park <sj@kernel.org>
---
 include/linux/damon.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index 33929a400aa7a..23df189015198 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -440,9 +440,9 @@ struct damos_stat {
  * All types except &DAMOS_FILTER_TYPE_ADDR, &DAMOS_FILTER_TYPE_TARGET and
  * &DAMOS_FILTER_TYPE_PROBE_HITS_WSUM are handled by the underlying &struct
  * damon_operations as a part of scheme action trying, and therefore accounted
- * as 'tried'.  In contrast, &DAMOS_FILTER_TYPE_ADDR and
- * &DAMOS_FILTER_TYPE_TARGET filters are handled by the core layer before
- * trying of the action, and therefore not accounted as 'tried'.
+ * as 'tried'.  In contrast, &DAMOS_FILTER_TYPE_ADDR, &DAMOS_FILTER_TYPE_TARGET
+ * and &DAMOS_FILTER_TYPE_PROBE_HITS_WSUM filters are handled by the core layer
+ * before trying of the action, and therefore not accounted as 'tried'.
  *
  * Support for the operations-handled filters depends on the running
  * &struct damon_operations.
--
2.47.3