From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from digeo-nav01.digeo.com (digeo-nav01.digeo.com [192.168.1.233]) by packet.digeo.com (8.9.3+Sun/8.9.3) with SMTP id JAA00362 for ; Wed, 25 Sep 2002 09:35:41 -0700 (PDT) Message-ID: <3D91E5DC.665EB3AC@digeo.com> Date: Wed, 25 Sep 2002 09:35:40 -0700 From: Andrew Morton MIME-Version: 1.0 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 Sender: owner-linux-mm@kvack.org Return-Path: To: frankeh@watson.ibm.com Cc: Mark_H_Johnson@raytheon.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: 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, 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/