From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [linux-pm] [PATCH] hibernation should work ok with memory hotplug Date: Tue, 4 Nov 2008 17:34:03 +0100 References: <20081029105956.GA16347@atrey.karlin.mff.cuni.cz> <200811041635.49932.rjw@sisk.pl> <1225813182.12673.587.camel@nimitz> In-Reply-To: <1225813182.12673.587.camel@nimitz> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200811041734.04802.rjw@sisk.pl> Sender: owner-linux-mm@kvack.org Return-Path: To: Dave Hansen Cc: Nigel Cunningham , Matt Tolentino , linux-pm@lists.osdl.org, Dave Hansen , linux-kernel@vger.kernel.org, linux-mm@kvack.org, pavel@suse.cz, Mel Gorman , Andy Whitcroft , Andrew Morton List-ID: On Tuesday, 4 of November 2008, Dave Hansen wrote: > On Tue, 2008-11-04 at 16:35 +0100, Rafael J. Wysocki wrote: > > On Tuesday, 4 of November 2008, Dave Hansen wrote: > > > On Tue, 2008-11-04 at 09:54 +0100, Rafael J. Wysocki wrote: > > > > To handle this, I need to know two things: > > > > 1) what changes of the zones are possible due to memory hotplugging > > > > (i.e. can they grow, shring, change boundaries etc.) > > > > > > All of the above. > > > > OK > > > > If I allocate a page frame corresponding to specific pfn, is it guaranteed to > > be associated with the same pfn in future? > > Page allocation is different. Since you hold a reference to a page, it > can not be removed until you release that reference. That's why every > normal alloc_pages() user in the kernel doesn't have to worry about > memory hotplug. Good. :-) So, if I allocate the image pages right prior to creating the image, they won't be touched by memory hotplug. Now, I need to do one more thing, which is to check how much memory has to be freed before creating the image. For this purpose I need to lock memory hotplug temporarily, count pages to free and unlock it. What interface should I use for this purpose? [I'll also need to lock memory hotplug temporarily during resume.] Rafael -- 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/ . Don't email: email@kvack.org