From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261189AbVFNNuI (ORCPT ); Tue, 14 Jun 2005 09:50:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261210AbVFNNuH (ORCPT ); Tue, 14 Jun 2005 09:50:07 -0400 Received: from gold.veritas.com ([143.127.12.110]:11385 "EHLO gold.veritas.com") by vger.kernel.org with ESMTP id S261189AbVFNNuB (ORCPT ); Tue, 14 Jun 2005 09:50:01 -0400 Date: Tue, 14 Jun 2005 14:51:05 +0100 (BST) From: Hugh Dickins X-X-Sender: hugh@goblin.wat.veritas.com To: li nux cc: William Lee Irwin III , linux-kernel@vger.kernel.org Subject: Re: rmap.c: try_to_unmap_file(): VM_LOCKED not respected In-Reply-To: <20050614051405.42342.qmail@web33307.mail.mud.yahoo.com> Message-ID: References: <20050614051405.42342.qmail@web33307.mail.mud.yahoo.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-OriginalArrivalTime: 14 Jun 2005 13:49:58.0780 (UTC) FILETIME=[F4444BC0:01C570E7] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 13 Jun 2005, li nux wrote: > My application is using remap_file_pages and mlocks > those pages. > So in the code of try_to_unmap_file (see below), > I should never reach the call to try_to_unmap_cluster, > because for those pages VM_LOCKED is always set. > But, under heavy load I am seeing try_to_unmap_cluster > is getting called. Stack: > try_to_unmap_cluster > try_to_unmap_file > try_to_unmap > shrink_list > > Any idea why VM_LOCKED is not being respected ? Does your application fork occasionally, probably to exec something? VM_LOCKED is masked off the flags of the child's copy vma (see dup_mmap), so you might be seeing page reclaim hitting the child in between fork and exec. The parent's should remain safely VM_LOCKED as you intended. Hugh