Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754979Ab0GHJCy (ORCPT ); Thu, 8 Jul 2010 05:02:54 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:53893 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752979Ab0GHJCw convert rfc822-to-8bit (ORCPT ); Thu, 8 Jul 2010 05:02:52 -0400 Subject: Re: FYI: mmap_sem OOM patch From: Peter Zijlstra To: Michel Lespinasse Cc: linux-mm , KOSAKI Motohiro , LKML , Divyesh Shah In-Reply-To: <20100707231134.GA26555@google.com> References: <20100707231134.GA26555@google.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Thu, 08 Jul 2010 11:02:48 +0200 Message-ID: <1278579768.1900.14.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 916 Lines: 25 On Wed, 2010-07-07 at 16:11 -0700, Michel Lespinasse wrote: > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > index f627779..4b3a1c7 100644 > --- a/arch/x86/mm/fault.c > +++ b/arch/x86/mm/fault.c > @@ -1062,7 +1062,10 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code) > bad_area_nosemaphore(regs, error_code, address); > return; > } > - down_read(&mm->mmap_sem); > + if (test_thread_flag(TIF_MEMDIE)) > + down_read_unfair(&mm->mmap_sem); > + else > + down_read(&mm->mmap_sem); > } else { > /* > * The above down_read_trylock() might have succeeded in I still think adding that _unfair interface is asking for trouble. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/