Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751398AbbEZEbf (ORCPT ); Tue, 26 May 2015 00:31:35 -0400 Received: from mail.phunq.net ([184.71.0.62]:50762 "EHLO starbase.phunq.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751142AbbEZEbd convert rfc822-to-8bit (ORCPT ); Tue, 26 May 2015 00:31:33 -0400 From: Daniel Phillips To: Rik van Riel Cc: David Lang , Jan Kara , , , , OGAWA Hirofumi Subject: Re: [FYI] tux3: Core changes Date: Mon, 25 May 2015 21:30:41 -0700 User-Agent: Trojita/v0.5-14-g8a2496c; Qt/4.8.6; X11; Linux; Ubuntu 14.04.2 LTS MIME-Version: 1.0 Message-ID: In-Reply-To: <5563F5C8.2040806@redhat.com> References: <8f886f13-6550-4322-95be-93244ae61045@phunq.net> <55545C2F.8040207@phunq.net> <20150519140045.GA16313@quack.suse.cz> <555B8C79.4090909@phunq.net> <20150520144429.GA17783@quack.suse.cz> <555CB4B6.8050305@phunq.net> <555CE62C.5030202@redhat.com> <555D0FDF.3070303@phunq.net> <555D500B.4080901@phunq.net> <13c8bcdf-70e8-43d5-a05f-58ad839dbfd0@phunq.net> <5563F5C8.2040806@redhat.com> Organization: tux3.org Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1269 Lines: 32 On Monday, May 25, 2015 9:25:44 PM PDT, Rik van Riel wrote: > On 05/21/2015 03:53 PM, Daniel Phillips wrote: >> On Wednesday, May 20, 2015 8:51:46 PM PDT, David Lang wrote: >>> how do you prevent it from continuing to interact with the old version >>> of the page and never see updates or have it's changes reflected on >>> the current page? >> >> Why would it do that, and what would be surprising about it? Did >> you have a specific case in mind? > > After a get_page(), page_cache_get(), or other equivalent > function, a piece of code has the expectation that it can > continue using that page until after it has released the > reference count. > > This can be an arbitrarily long period of time. It is perfectly welcome to keep using that page as long as it wants, Tux3 does not care. When it lets go of the last reference (and Tux3 has finished with it) then the page is freeable. Did you have a more specific example where this would be an issue? Are you talking about kernel or userspace code? Regards, Daniel -- 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/