Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 25 Sep 2002 12:30:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 25 Sep 2002 12:30:33 -0400 Received: from packet.digeo.com ([12.110.80.53]:3526 "EHLO packet.digeo.com") by vger.kernel.org with ESMTP id ; Wed, 25 Sep 2002 12:30:32 -0400 Message-ID: <3D91E5DC.665EB3AC@digeo.com> Date: Wed, 25 Sep 2002 09:35:40 -0700 From: Andrew Morton X-Mailer: Mozilla 4.79 [en] (X11; U; Linux 2.4.19-rc5 i686) X-Accept-Language: en MIME-Version: 1.0 To: frankeh@watson.ibm.com CC: Mark_H_Johnson@raytheon.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] recognize MAP_LOCKED in mmap() call References: <3D88D9DE.2FB9A23D@digeo.com> <200209251142.29341.frankeh@watson.ibm.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 25 Sep 2002 16:35:41.0236 (UTC) FILETIME=[963CEF40:01C264B1] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1438 Lines: 33 Hubertus Franke wrote: > > ... > This is what the manpage says... > > mlockall disables paging for all pages mapped into the > address space of the calling process. This includes the > pages of the code, data and stack segment, as well as > shared libraries, user space kernel data, shared memory > and memory mapped files. All mapped pages are guaranteed > to be resident in RAM when the mlockall system call > returns successfully and they are guaranteed to stay in > RAM until the pages are unlocked again by munlock or > munlockall or until the process terminates or starts > another program with exec. Child processes do not inherit > page locks across a fork. > > Do you read that all pages must be faulted in apriori ? For MCL_FUTURE. > Or is it sufficient to to make sure non of the currently mapped > pages are swapped out and future swapout is prohibited. I'd say that we should try to make all the pages present. But if it's a problem for (say) a hugepage implementation then it's unlikely that the world would end if these things were still demand paged in. - 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/