mm: Add PGREUSE counter

This accounts for wp_page_reuse() case, where we reused a page for COW. Signed-off-by: Peter Xu <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
LoveHeat · Sep 4, 2020 · 798a6b8 · 798a6b8
1 parent a308c71
commit 798a6b8
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diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
@@ -30,6 +30,7 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
 		PGFAULT, PGMAJFAULT,
 		PGLAZYFREED,
 		PGREFILL,
+		PGREUSE,
 		PGSTEAL_KSWAPD,
 		PGSTEAL_DIRECT,
 		PGSCAN_KSWAPD,

diff --git a/mm/memory.c b/mm/memory.c
@@ -2619,6 +2619,7 @@ static inline void wp_page_reuse(struct vm_fault *vmf)
 	if (ptep_set_access_flags(vma, vmf->address, vmf->pte, entry, 1))
 		update_mmu_cache(vma, vmf->address, vmf->pte);
 	pte_unmap_unlock(vmf->pte, vmf->ptl);
+	count_vm_event(PGREUSE);
 }
 
 /*

diff --git a/mm/vmstat.c b/mm/vmstat.c
@@ -1198,6 +1198,7 @@ const char * const vmstat_text[] = {
 	"pglazyfreed",
 
 	"pgrefill",
+	"pgreuse",
 	"pgsteal_kswapd",
 	"pgsteal_direct",
 	"pgscan_kswapd",