From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932078Ab3JIR0M (ORCPT ); Wed, 9 Oct 2013 13:26:12 -0400 Received: from terminus.zytor.com ([198.137.202.10]:55958 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755761Ab3JIR0J (ORCPT ); Wed, 9 Oct 2013 13:26:09 -0400 Date: Wed, 9 Oct 2013 10:25:32 -0700 From: tip-bot for Mel Gorman Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, peterz@infradead.org, hannes@cmpxchg.org, riel@redhat.com, aarcange@redhat.com, srikar@linux.vnet.ibm.com, mgorman@suse.de, tglx@linutronix.de Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, peterz@infradead.org, hannes@cmpxchg.org, riel@redhat.com, aarcange@redhat.com, srikar@linux.vnet.ibm.com, mgorman@suse.de, tglx@linutronix.de In-Reply-To: <1381141781-10992-11-git-send-email-mgorman@suse.de> References: <1381141781-10992-11-git-send-email-mgorman@suse.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] mm: Do not flush TLB during protection change if !pte_present && !migration_entry Git-Commit-ID: e920e14ca29b0b2a981cfc90e4e20edd6f078d19 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Wed, 09 Oct 2013 10:25:39 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: e920e14ca29b0b2a981cfc90e4e20edd6f078d19 Gitweb: http://git.kernel.org/tip/e920e14ca29b0b2a981cfc90e4e20edd6f078d19 Author: Mel Gorman AuthorDate: Mon, 7 Oct 2013 11:28:48 +0100 Committer: Ingo Molnar CommitDate: Wed, 9 Oct 2013 12:39:48 +0200 mm: Do not flush TLB during protection change if !pte_present && !migration_entry NUMA PTE scanning is expensive both in terms of the scanning itself and the TLB flush if there are any updates. Currently non-present PTEs are accounted for as an update and incurring a TLB flush where it is only necessary for anonymous migration entries. This patch addresses the problem and should reduce TLB flushes. Cc: Andrea Arcangeli Cc: Johannes Weiner Cc: Srikar Dronamraju Reviewed-by: Rik van Riel Signed-off-by: Mel Gorman Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1381141781-10992-11-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar --- mm/mprotect.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/mprotect.c b/mm/mprotect.c index 2bbb648..7bdbd4b 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -101,8 +101,9 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, make_migration_entry_read(&entry); set_pte_at(mm, addr, pte, swp_entry_to_pte(entry)); + + pages++; } - pages++; } } while (pte++, addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode();