From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263664AbUHTHzh (ORCPT ); Fri, 20 Aug 2004 03:55:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267620AbUHTHzh (ORCPT ); Fri, 20 Aug 2004 03:55:37 -0400 Received: from mail1.kontent.de ([81.88.34.36]:8870 "EHLO Mail1.KONTENT.De") by vger.kernel.org with ESMTP id S263664AbUHTHzc (ORCPT ); Fri, 20 Aug 2004 03:55:32 -0400 From: Oliver Neukum To: Nick Piggin Subject: Re: PF_MEMALLOC in 2.6 Date: Fri, 20 Aug 2004 09:56:50 +0200 User-Agent: KMail/1.6.2 Cc: Hugh Dickins , Pete Zaitcev , arjanv@redhat.com, alan@redhat.com, greg@kroah.com, linux-kernel@vger.kernel.org, riel@redhat.com, sct@redhat.com References: <200408192025.53536.oliver@neukum.org> <412563F6.1080202@yahoo.com.au> In-Reply-To: <412563F6.1080202@yahoo.com.au> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <200408200956.50972.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Freitag, 20. August 2004 04:37 schrieb Nick Piggin: > So if this thing allocates memory on behalf of a read request, then > it is basically a bug. In practice you could probably get away with > servicing all writes with PF_MEMALLOC, however that could still lead > to situations where it consumes all your low memory on behalf of > highmem IO (though perhaps this won't deadlock if that memory is > going to be released as a matter of course?) > > Another thing, having it always use PF_MEMALLOC means it can easily > wipe out the GFP_ATOMIC reserve. > > So I'd say try to find a way to only use PF_MEMALLOC on behalf of > a PF_MEMALLOC thread or use a mempool or something. Then the SCSI layer should pass down the flag. Regards Oliver