From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx158.postini.com [74.125.245.158]) by kanga.kvack.org (Postfix) with SMTP id 9033F6B004A for ; Tue, 24 Apr 2012 20:07:07 -0400 (EDT) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id 2DEED3EE0AE for ; Wed, 25 Apr 2012 09:07:06 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 11C4845DE7E for ; Wed, 25 Apr 2012 09:07:06 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id E7A2245DEB7 for ; Wed, 25 Apr 2012 09:07:05 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id D48A61DB8044 for ; Wed, 25 Apr 2012 09:07:05 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.240.81.134]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 89D991DB803F for ; Wed, 25 Apr 2012 09:07:05 +0900 (JST) Message-ID: <4F973FB8.6050103@jp.fujitsu.com> Date: Wed, 25 Apr 2012 09:05:12 +0900 From: KAMEZAWA Hiroyuki MIME-Version: 1.0 Subject: Re: [RFC] propagate gfp_t to page table alloc functions References: <1335171318-4838-1-git-send-email-minchan@kernel.org> <4F963742.2030607@jp.fujitsu.com> <4F963B8E.9030105@kernel.org> <4F965413.9010305@kernel.org> <20120424143015.99fd8d4a.akpm@linux-foundation.org> <4F973BF2.4080406@jp.fujitsu.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: KOSAKI Motohiro Cc: Andrew Morton , Nick Piggin , Minchan Kim , Ingo Molnar , x86@kernel.org, Hugh Dickins , Johannes Weiner , Rik van Riel , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org (2012/04/25 8:55), KOSAKI Motohiro wrote: > On Tue, Apr 24, 2012 at 7:49 PM, KAMEZAWA Hiroyuki > wrote: >> (2012/04/25 6:30), Andrew Morton wrote: >> >>> On Tue, 24 Apr 2012 17:48:29 +1000 >>> Nick Piggin wrote: >>> >>>>> Hmm, there are several places to use GFP_NOIO and GFP_NOFS even, GFP_ATOMIC. >>>>> I believe it's not trivial now. >>>> >>>> They're all buggy then. Unfortunately not through any real fault of their own. >>> >>> There are gruesome problems in block/blk-throttle.c (thread "mempool, >>> percpu, blkcg: fix percpu stat allocation and remove stats_lock"). It >>> wants to do an alloc_percpu()->vmalloc() from the IO submission path, >>> under GFP_NOIO. >>> >>> Changing vmalloc() to take a gfp_t does make lots of sense, although I >>> worry a bit about making vmalloc() easier to use! >>> >>> I do wonder whether the whole scheme of explicitly passing a gfp_t was >>> a mistake and that the allocation context should be part of the task >>> context. ie: pass the allocation mode via *current. >> >> yes...that's very interesting. > > I think GFP_ATOMIC is used non task context too. ;-) Hmm, in interrupt context or some ? Can't we detect it ? Thanks, -Kame -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org