[RFC PATCH 1/6] mm/damon/api: introduce DAMOS_FILTER_TYPE_PROBE_HITS_WSUM

[SJ Park <sj@kernel.org>]

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 | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index 871d26adf6ae5..59d57131d8327 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -399,6 +399,7 @@ 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
@@ -420,6 +421,7 @@ enum damos_filter_type {
 	DAMOS_FILTER_TYPE_UNMAPPED,
 	DAMOS_FILTER_TYPE_ADDR,
 	DAMOS_FILTER_TYPE_TARGET,
+	DAMOS_FILTER_TYPE_PROBE_HITS_WSUM,
 	NR_DAMOS_FILTER_TYPES,
 };
 
@@ -434,6 +436,8 @@ enum damos_filter_type {
  *		&damon_ctx->adaptive_targets if @type is
  *		DAMOS_FILTER_TYPE_TARGET.
  * @sz_range:	Size range if @type is DAMOS_FILTER_TYPE_HUGEPAGE_SIZE.
+ * @range_min:	Minimum value of range arguments.
+ * @range_mx:	Maximum value of range arguments.
  *
  * Before applying the &damos->action to a memory region, DAMOS checks if each
  * byte of the region matches to this given condition and avoid applying the
@@ -450,6 +454,10 @@ struct damos_filter {
 		struct damon_addr_range addr_range;
 		int target_idx;
 		struct damon_size_range sz_range;
+		struct {
+			unsigned long range_min;
+			unsigned long range_max;
+		};
 	};
 /* private: */
 	/* List head for siblings. */
-- 
2.47.3