From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id 2457B8D0040 for ; Mon, 28 Mar 2011 20:55:18 -0400 (EDT) Subject: Re: [PATCH]mmap: add alignment for some variables From: Shaohua Li In-Reply-To: References: <1301277536.3981.27.camel@sli10-conroe> Content-Type: text/plain; charset="UTF-8" Date: Tue, 29 Mar 2011 08:54:14 +0800 Message-ID: <1301360054.3981.31.camel@sli10-conroe> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andi Kleen Cc: Andrew Morton , linux-mm , lkml , Rik van Riel , Hugh Dickins On Tue, 2011-03-29 at 00:55 +0800, Andi Kleen wrote: > Shaohua Li writes: > > > Make some variables have correct alignment. > > Nit: __read_mostly doesn't change alignment, just the section. > Please fix the description. Other than that it looks good. sure. Make some variables have correct alignment/section to avoid cache issue. In a workload which heavily does mmap/munmap, the variables will be used frequently. Signed-off-by: Shaohua Li --- mm/mmap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) Index: linux/mm/mmap.c =================================================================== --- linux.orig/mm/mmap.c 2011-03-29 08:30:12.000000000 +0800 +++ linux/mm/mmap.c 2011-03-29 08:30:54.000000000 +0800 @@ -84,10 +84,10 @@ pgprot_t vm_get_page_prot(unsigned long } EXPORT_SYMBOL(vm_get_page_prot); -int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */ -int sysctl_overcommit_ratio = 50; /* default is 50% */ +int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_GUESS; /* heuristic overcommit */ +int sysctl_overcommit_ratio __read_mostly = 50; /* default is 50% */ int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT; -struct percpu_counter vm_committed_as; +struct percpu_counter vm_committed_as ____cacheline_internodealigned_in_smp; /* * Check that a process has enough memory to allocate a new virtual -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org