lkml.org 
[lkml]   [2021]   [Oct]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC 2/8] mm/hugetlb: remove useless set_page_count()
Date
prep_compound_gigantic_page() calls set_page_count(0, p), but it is not
needed because page_ref_freeze(p, 1) already sets refcount to 0.

Using, set_page_count() is dangerous, because it unconditionally resets
refcount from the current value to unrestrained value, and therefore
should be minimized.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
---
mm/hugetlb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 95dc7b83381f..7e3996c8b696 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1707,7 +1707,7 @@ static bool prep_compound_gigantic_page(struct page *page, unsigned int order)
pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n");
goto out_error;
}
- set_page_count(p, 0);
+ VM_BUG_ON_PAGE(page_count(p), p);
set_compound_head(p, page);
}
atomic_set(compound_mapcount_ptr(page), -1);
--
2.33.0.1079.g6e70778dc9-goog
\
 
 \ /
  Last update: 2021-10-26 19:39    [W:0.239 / U:0.080 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site