[RFC PATCH 2/6] mm/damon/core: support probe_hits_wsum damos core filter

[SJ Park <sj@kernel.org>]

Implement probe_hits_wsum DAMOS core filter support in the core layer.
Make three small changes for the support.  First, update
damos_filter_for_ops() to treat probe_hits_wsum filter as core filter.
Second, Update destination damos_filter->range_{min,max} for
probe_hits_wsum type damos filter commits.  Third, extend
damos_filter_match() to handle probe_hits_wsum type filter. Calculate
the weighted sum of the given region and compare it with the given
filter's target weighted sum range.

Signed-off-by: SJ Park <sj@kernel.org>
---
 mm/damon/core.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index 1752afede01e2..5b976162c5eed 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -654,6 +654,7 @@ bool damos_filter_for_ops(enum damos_filter_type type)
 	switch (type) {
 	case DAMOS_FILTER_TYPE_ADDR:
 	case DAMOS_FILTER_TYPE_TARGET:
+	case DAMOS_FILTER_TYPE_PROBE_HITS_WSUM:
 		return false;
 	default:
 		break;
@@ -1328,6 +1329,10 @@ static void damos_commit_filter_arg(
 	case DAMOS_FILTER_TYPE_HUGEPAGE_SIZE:
 		dst->sz_range = src->sz_range;
 		break;
+	case DAMOS_FILTER_TYPE_PROBE_HITS_WSUM:
+		dst->range_min = src->range_min;
+		dst->range_max = src->range_max;
+		break;
 	default:
 		break;
 	}
@@ -2506,7 +2511,7 @@ static bool damos_filter_match(struct damon_ctx *ctx, struct damon_target *t,
 	bool matched = false;
 	struct damon_target *ti;
 	int target_idx = 0;
-	unsigned long start, end;
+	unsigned long start, end, wsum;
 
 	switch (filter->type) {
 	case DAMOS_FILTER_TYPE_TARGET:
@@ -2541,6 +2546,11 @@ static bool damos_filter_match(struct damon_ctx *ctx, struct damon_target *t,
 		damon_split_region_at(t, r, end - r->ar.start);
 		matched = true;
 		break;
+	case DAMOS_FILTER_TYPE_PROBE_HITS_WSUM:
+		wsum = damon_probe_hits_wsum(r, false, ctx);
+		matched = filter->range_min <= wsum &&
+			wsum <= filter->range_max;
+		break;
 	default:
 		return false;
 	}
-- 
2.47.3