mm/damon/paddr: report filter-passed bytes back for normal actions

damon_operations->apply_scheme() implementations are requested to report
back how many bytes of the given region has passed DAMOS filter.  'paddr'
operations set implementation supports some of region-internal DAMOS
filter handling for normal DAMOS actions except DAMOS_STAT action.  But,
those are not respecting the request.  Report the region-internal DAMOS
filter-passed bytes back for the actions.

Link: https://lkml.kernel.org/r/20250106193401.109161-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 3530ef9c80bd76bdc8272e32d2dbe96d419a6b79..5944316a0b4cdd08bc111cd59bacddb5b8624127 100644 (file)
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -243,7 +243,8 @@ static bool damos_pa_filter_out(struct damos *scheme, struct folio *folio)
        return false;
 }
 
-static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s)
+static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s,
+               unsigned long *sz_filter_passed)
 {
        unsigned long addr, applied;
        LIST_HEAD(folio_list);
@@ -272,6 +273,8 @@ static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s)
 
                if (damos_pa_filter_out(s, folio))
                        goto put_folio;
+               else
+                       *sz_filter_passed += folio_size(folio);
 
                folio_clear_referenced(folio);
                folio_test_clear_young(folio);
@@ -292,7 +295,8 @@ put_folio:
 }
 
 static inline unsigned long damon_pa_mark_accessed_or_deactivate(
-               struct damon_region *r, struct damos *s, bool mark_accessed)
+               struct damon_region *r, struct damos *s, bool mark_accessed,
+               unsigned long *sz_filter_passed)
 {
        unsigned long addr, applied = 0;
 
@@ -304,6 +308,8 @@ static inline unsigned long damon_pa_mark_accessed_or_deactivate(
 
                if (damos_pa_filter_out(s, folio))
                        goto put_folio;
+               else
+                       *sz_filter_passed += folio_size(folio);
 
                if (mark_accessed)
                        folio_mark_accessed(folio);
@@ -317,15 +323,17 @@ put_folio:
 }
 
 static unsigned long damon_pa_mark_accessed(struct damon_region *r,
-       struct damos *s)
+       struct damos *s, unsigned long *sz_filter_passed)
 {
-       return damon_pa_mark_accessed_or_deactivate(r, s, true);
+       return damon_pa_mark_accessed_or_deactivate(r, s, true,
+                       sz_filter_passed);
 }
 
 static unsigned long damon_pa_deactivate_pages(struct damon_region *r,
-       struct damos *s)
+       struct damos *s, unsigned long *sz_filter_passed)
 {
-       return damon_pa_mark_accessed_or_deactivate(r, s, false);
+       return damon_pa_mark_accessed_or_deactivate(r, s, false,
+                       sz_filter_passed);
 }
 
 static unsigned int __damon_pa_migrate_folio_list(
@@ -449,7 +457,8 @@ static unsigned long damon_pa_migrate_pages(struct list_head *folio_list,
        return nr_migrated;
 }
 
-static unsigned long damon_pa_migrate(struct damon_region *r, struct damos *s)
+static unsigned long damon_pa_migrate(struct damon_region *r, struct damos *s,
+               unsigned long *sz_filter_passed)
 {
        unsigned long addr, applied;
        LIST_HEAD(folio_list);
@@ -462,6 +471,8 @@ static unsigned long damon_pa_migrate(struct damon_region *r, struct damos *s)
 
                if (damos_pa_filter_out(s, folio))
                        goto put_folio;
+               else
+                       *sz_filter_passed += folio_size(folio);
 
                if (!folio_isolate_lru(folio))
                        goto put_folio;
@@ -481,14 +492,14 @@ static unsigned long damon_pa_apply_scheme(struct damon_ctx *ctx,
 {
        switch (scheme->action) {
        case DAMOS_PAGEOUT:
-               return damon_pa_pageout(r, scheme);
+               return damon_pa_pageout(r, scheme, sz_filter_passed);
        case DAMOS_LRU_PRIO:
-               return damon_pa_mark_accessed(r, scheme);
+               return damon_pa_mark_accessed(r, scheme, sz_filter_passed);
        case DAMOS_LRU_DEPRIO:
-               return damon_pa_deactivate_pages(r, scheme);
+               return damon_pa_deactivate_pages(r, scheme, sz_filter_passed);
        case DAMOS_MIGRATE_HOT:
        case DAMOS_MIGRATE_COLD:
-               return damon_pa_migrate(r, scheme);
+               return damon_pa_migrate(r, scheme, sz_filter_passed);
        case DAMOS_STAT:
                break;
        default: