From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id B05268D0040 for ; Fri, 25 Mar 2011 11:14:23 -0400 (EDT) Received: by fxm18 with SMTP id 18so1534861fxm.14 for ; Fri, 25 Mar 2011 08:14:18 -0700 (PDT) Date: Fri, 25 Mar 2011 16:13:53 +0100 From: Tejun Heo Subject: Re: [GIT PULL] SLAB changes for v2.6.39-rc1 Message-ID: <20110325151353.GG1409@htj.dyndns.org> References: <20110324185903.GA30510@elte.hu> <20110324193647.GA7957@elte.hu> <1300997290.2714.2.camel@edumazet-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: Eric Dumazet , Pekka Enberg , Ingo Molnar , torvalds@linux-foundation.org, akpm@linux-foundation.org, npiggin@kernel.dk, David Rientjes , linux-kernel@vger.kernel.org, linux-mm@kvack.org Hello, On Thu, Mar 24, 2011 at 03:43:25PM -0500, Christoph Lameter wrote: > > Thats strange, alloc_percpu() is supposed to zero the memory already ... > > True. > > > Are you sure its really this problem of interrupts being disabled ? > > Guess so since Ingo and Pekka reported that it fixed the problem. > > Tejun: Can you help us with this mystery? I've looked through the code but can't figure out what the difference is. The memset code is in mm/percpu-vm.c::pcpu_populate_chunk(). for_each_possible_cpu(cpu) memset((void *)pcpu_chunk_addr(chunk, cpu, 0) + off, 0, size); (pcpu_chunk_addr(chunk, cpu, 0) + off) is the same vaddr as will be obtained by per_cpu_ptr(ptr, cpu), so all allocated memory regions are accessed before being returned. Dazed and confused (seems like the theme of today for me). Could it be that the vmalloc page is taking more than one faults? Thanks. -- tejun -- 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