From c01a885e94b6edb8545113d3ba43248b4b75e90c Mon Sep 17 00:00:00 2001
From: Alex Lapenkou <lapenkov@fb.com>
Date: Thu, 19 Aug 2021 15:16:11 -0700
Subject: [PATCH] HPA: Correctly calculate retained pages

Retained pages are those which haven't been touched and are unbacked from OS
perspective. For a pageslab their number should equal "total pages in slab"
minus "touched pages".
---
 include/jemalloc/internal/hpdata.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/jemalloc/internal/hpdata.h b/include/jemalloc/internal/hpdata.h
index c2ed692b..1fb534db 100644
--- a/include/jemalloc/internal/hpdata.h
+++ b/include/jemalloc/internal/hpdata.h
@@ -292,7 +292,7 @@ hpdata_ndirty_get(hpdata_t *hpdata) {
 
 static inline size_t
 hpdata_nretained_get(hpdata_t *hpdata) {
-	return hpdata->h_nactive - hpdata->h_ntouched;
+	return HUGEPAGE_PAGES - hpdata->h_ntouched;
 }
 
 static inline void