From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f177.google.com (mail-pd0-f177.google.com [209.85.192.177]) by kanga.kvack.org (Postfix) with ESMTP id 2564D6B0031 for ; Thu, 12 Dec 2013 08:42:03 -0500 (EST) Received: by mail-pd0-f177.google.com with SMTP id q10so518199pdj.8 for ; Thu, 12 Dec 2013 05:42:02 -0800 (PST) Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) by mx.google.com with ESMTPS id 2si14865011pax.167.2013.12.12.05.41.59 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 12 Dec 2013 05:42:00 -0800 (PST) Received: by mail-pd0-f178.google.com with SMTP id y10so525884pdj.9 for ; Thu, 12 Dec 2013 05:41:59 -0800 (PST) Message-ID: <52A9BD23.9010902@linaro.org> Date: Thu, 12 Dec 2013 21:41:55 +0800 From: Alex Shi MIME-Version: 1.0 Subject: Re: [PATCH 3/3] x86: mm: Account for the of CPUs that must be flushed during a TLB range flush References: <1386849309-22584-1-git-send-email-mgorman@suse.de> <1386849309-22584-4-git-send-email-mgorman@suse.de> In-Reply-To: <1386849309-22584-4-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: H Peter Anvin , Linux-X86 , Linux-MM , LKML On 12/12/2013 07:55 PM, Mel Gorman wrote: > X86 TLB range flushing uses a balance point to decide if a single global TLB > flush or multiple single page flushes would perform best. This patch takes into > account how many CPUs must be flushed. > > Signed-off-by: Mel Gorman > --- > arch/x86/mm/tlb.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c > index 09b8cb8..0cababa 100644 > --- a/arch/x86/mm/tlb.c > +++ b/arch/x86/mm/tlb.c > @@ -217,6 +217,9 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, > act_entries = mm->total_vm > act_entries ? act_entries : mm->total_vm; > nr_base_pages = (end - start) >> PAGE_SHIFT; > > + /* Take the number of CPUs to range flush into account */ > + nr_base_pages *= cpumask_weight(mm_cpumask(mm)); > + flush range calculation base on per cpu, since no matter how many cpus in the process, tlb flush and refill time won't change. > /* tlb_flushall_shift is on balance point, details in commit log */ > if (nr_base_pages > act_entries || has_large_page(mm, start, end)) { > count_vm_event(NR_TLB_LOCAL_FLUSH_ALL); > -- Thanks Alex -- 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