Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754012Ab3HVQvf (ORCPT ); Thu, 22 Aug 2013 12:51:35 -0400 Received: from a9-66.smtp-out.amazonses.com ([54.240.9.66]:44667 "EHLO a9-66.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753552Ab3HVQvd (ORCPT ); Thu, 22 Aug 2013 12:51:33 -0400 X-Greylist: delayed 442 seconds by postgrey-1.27 at vger.kernel.org; Thu, 22 Aug 2013 12:51:33 EDT Date: Thu, 22 Aug 2013 16:44:09 +0000 From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Andrew Morton cc: "Nicholas A. Bellinger" , Kent Overstreet , linux-kernel@vger.kernel.org, Tejun Heo , Oleg Nesterov , Ingo Molnar , Andi Kleen , Jens Axboe Subject: Re: [PATCH] idr: Use this_cpu_ptr() for percpu_ida In-Reply-To: <20130821134945.16b32c045e28272c5b0ba610@linux-foundation.org> Message-ID: <00000140a6e964d2-03ac778f-13ff-415d-bbfa-93cb2fddcaa5-000000@email.amazonses.com> References: <1375896905-6074-1-git-send-email-kmo@daterainc.com> <1375896905-6074-5-git-send-email-kmo@daterainc.com> <0000014059ec4c34-1bb53d48-c9ee-4e71-81b8-253026431c5c-000000@email.amazonses.com> <20130807183345.GA11612@kmo-pixel> <000001405a4b39ef-0715410a-5061-41e9-9414-86559f16570d-000000@email.amazonses.com> <20130807195733.GB11612@kmo-pixel> <000001405e5776ba-bcc96088-b5e8-4abe-b98e-2e9d7d9b112b-000000@email.amazonses.com> <1377033546.32763.4.camel@haakon3.risingtidesystems.com> <00000140a14ae6bb-f0fca267-cdd6-4039-8c6b-f715999a83c5-000000@email.amazonses.com> <20130821134945.16b32c045e28272c5b0ba610@linux-foundation.org> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SES-Outgoing: 2013.08.22-54.240.9.66 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 478 Lines: 12 On Wed, 21 Aug 2013, Andrew Morton wrote: > The lock is needed so that one cpu can steal tags from another cpu's cache. > See (the needlessly inlined!) steal_tags(). Stealing tags could also be done via IPIs or some other things. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/