From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 5FE306003C1 for ; Tue, 26 Jan 2010 10:56:22 -0500 (EST) Date: Tue, 26 Jan 2010 09:55:43 -0600 (CST) From: Christoph Lameter Subject: Re: [PATCH 00 of 30] Transparent Hugepage support #3 In-Reply-To: <20100126123533.GF30452@random.random> Message-ID: References: <20100122151947.GA3690@random.random> <20100123175847.GC6494@random.random> <4B5E3CC0.2060006@redhat.com> <20100126065303.GJ8483@redhat.com> <20100126123533.GF30452@random.random> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Andrea Arcangeli Cc: Gleb Natapov , Rik van Riel , linux-mm@kvack.org, Marcelo Tosatti , Adam Litke , Avi Kivity , Izik Eidus , Hugh Dickins , Nick Piggin , Mel Gorman , Andi Kleen , Dave Hansen , Benjamin Herrenschmidt , Ingo Molnar , Mike Travis , KAMEZAWA Hiroyuki , Chris Wright , Andrew Morton List-ID: On Tue, 26 Jan 2010, Andrea Arcangeli wrote: > gup already does the trick of preventing swapping of only the pieces > that are pinned. But it's ok only for temporary direct access like > DMA, ideally if the access to the page can be stopped synchronously > and the mapping is longstanding (not something dma can do, so O_DIRECT > can't do) mmu notifier should be used to allow paging of the page and > teardown the secondary mmu mapping. How does it do that? Take a reference on each of the 512 pieces? Or does it take one reference? -- 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