linux-kernel - [PATCH 12/35] Remove a branch by assuming __GFP_HIGH == ALLOC

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 16 Mar 2009 09:46:07 +0000
From:	Mel Gorman <mel@....ul.ie>
To:	Mel Gorman <mel@....ul.ie>,
	Linux Memory Management List <linux-mm@...ck.org>
Cc:	Pekka Enberg <penberg@...helsinki.fi>,
	Rik van Riel <riel@...hat.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Christoph Lameter <cl@...ux-foundation.org>,
	Johannes Weiner <hannes@...xchg.org>,
	Nick Piggin <npiggin@...e.de>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Lin Ming <ming.m.lin@...el.com>,
	Zhang Yanmin <yanmin_zhang@...ux.intel.com>,
	Peter Zijlstra <peterz@...radead.org>
Subject: [PATCH 12/35] Remove a branch by assuming __GFP_HIGH == ALLOC_HIGH

Allocations that specify __GFP_HIGH get the ALLOC_HIGH flag. If these
flags are equal to each other, we can eliminate a branch.

[akpm@...ux-foundation.org: Suggested the hack]
Signed-off-by: Mel Gorman <mel@....ul.ie>
---
 mm/page_alloc.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ad26052..1e8b4b6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1640,8 +1640,8 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
 	 * policy or is asking for __GFP_HIGH memory.  GFP_ATOMIC requests will
 	 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
 	 */
-	if (gfp_mask & __GFP_HIGH)
-		alloc_flags |= ALLOC_HIGH;
+	VM_BUG_ON(__GFP_HIGH != ALLOC_HIGH);
+	alloc_flags |= (gfp_mask & __GFP_HIGH);
 
 	if (!wait) {
 		alloc_flags |= ALLOC_HARDER;
-- 
1.5.6.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/