mm/damon/paddr: increment pa_stat damon address range by folio size

This is to avoid going through all the pages in a folio.  For folio_size >
PAGE_SIZE, damon_get_folio will return NULL for tail pages, so the for
loop in those instances will be a nop.  Have a more efficient loop by just
incrementing the address by folio_size.

Link: https://lkml.kernel.org/r/20250113190738.1156381-1-usamaarif642@gmail.com
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 6b4397de419952546a43ae21941dee12cd434af4..bd8cfe10121bab033aa582d317bc275a9545601a 100644 (file)
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -504,17 +504,21 @@ static unsigned long damon_pa_stat(struct damon_region *r, struct damos *s,
        if (!damon_pa_scheme_has_filter(s))
                return 0;
 
-       for (addr = r->ar.start; addr < r->ar.end; addr += PAGE_SIZE) {
+       addr = r->ar.start;
+       while (addr < r->ar.end) {
                struct folio *folio = damon_get_folio(PHYS_PFN(addr));
 
-               if (!folio)
+               if (!folio) {
+                       addr += PAGE_SIZE;
                        continue;
+               }
 
                if (damos_pa_filter_out(s, folio))
                        goto put_folio;
                else
                        *sz_filter_passed += folio_size(folio);
 put_folio:
+               addr += folio_size(folio);
                folio_put(folio);
        }
        return 0;