From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 5267E6B0078 for ; Tue, 21 Sep 2010 12:18:24 -0400 (EDT) Date: Tue, 21 Sep 2010 12:18:18 -0400 From: Rik van Riel Subject: [PATCH] mm: do not print backtraces on GFP_ATOMIC failures Message-ID: <20100921121818.4745f038@annuminas.surriel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, KOSAKI Motohiro List-ID: Atomic allocations cannot fall back to the page eviction code and are expected to fail. In fact, in some network intensive workloads, it is common to experience hundreds of GFP_ATOMIC allocation failures. Printing out a backtrace for every one of those expected allocation failures accomplishes nothing good. At multi-gigabit network speeds with jumbo frames, a burst of allocation failure backtraces could even slow down the system. We're better off not printing out backtraces on GFP_ATOMIC allocation failures. Signed-off-by: Rik van Riel diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 975609c..5a0bddb 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -72,7 +72,7 @@ struct vm_area_struct; /* This equals 0, but use constants in case they ever change */ #define GFP_NOWAIT (GFP_ATOMIC & ~__GFP_HIGH) /* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */ -#define GFP_ATOMIC (__GFP_HIGH) +#define GFP_ATOMIC (__GFP_HIGH | __GFP_NOWARN) #define GFP_NOIO (__GFP_WAIT) #define GFP_NOFS (__GFP_WAIT | __GFP_IO) #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org