From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 25 Sep 2000 13:08:05 -0300 (BRST) From: Rik van Riel Subject: Re: refill_inactive() In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Ingo Molnar Cc: Roger Larsson , Linus Torvalds , MM mailing list , linux-kernel@vger.kernel.org List-ID: On Mon, 25 Sep 2000, Ingo Molnar wrote: > > On Mon, 25 Sep 2000, Rik van Riel wrote: > > > 2) you are right, we /can/ schedule when __GFP_IO isn't set, this is > > mistake ... now I'm getting confused about what __GFP_IO is all > > about, does anybody know the _exact_ meaning of __GFP_IO ? > > __GFP_IO set to 1 means that the allocator can afford doing IO implicitly > by the page allocator. Most allocations dont care at all wether swap IO is > started as part of gfp() or not. But a prominent counter-example is > GFP_BUFFER, which is used by the buffer-cache/fs layer, and which cannot > do any IO implicitly. (because it *is* the IO layer already, and it is > already trying to do IO.) The other reason are legacy lowlevel-filesystem > locks like the ext2fs lock, which cannot be taken recursively. Hmmm, doesn't GFP_BUFFER simply imply that we cannot allocate new buffer heads to do IO with?? (from reading buffer.c, I can't see much of a reason why we couldn't start write IO on already allocated buffers...) regards, Rik -- "What you're running that piece of shit Gnome?!?!" -- Miguel de Icaza, UKUUG 2000 http://www.conectiva.com/ http://www.surriel.com/ -- 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.eu.org/Linux-MM/