From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63A58C6FD1D for ; Tue, 21 Mar 2023 10:02:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229821AbjCUKC3 (ORCPT ); Tue, 21 Mar 2023 06:02:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbjCUKC1 (ORCPT ); Tue, 21 Mar 2023 06:02:27 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0A28A5DB for ; Tue, 21 Mar 2023 03:02:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=2GLEz1+QJs+kFY+hGZ6CoHL0v1zUnas+jB4FGiPXUtM=; b=onuRPZZyXZ+tY1cWs0XHakJWKQ cXBpeI5g9HhTYF46TcmgJb4XUZrB2YK2801B8LJnT7/gsRI+D2fQ48aRRYSUjv3DyPGh4+Etcn8/6 Ijctvuhlv8c287XaWtSrxrSJI1l/Jq2v8eyaoB08gaMo63fhwOyj2BsNcdBVnqld7BtqqdFJjIAlg sQwCsfgQ/n+iZWWIMx3bBpPZP3gHpm29S/G7lErO4s3FuSR6j6zFULaFPG1I9lteFtCr5PBuwgnVb iXGf6U827rdotLEkDODMZFp0HFCWhgy4XDZTNKs7p8eDPaqI0PyQE1zrm9JvAVKU5aFHoa0ldbhDZ f2Kv9eIQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1peYoj-004E4m-1T; Tue, 21 Mar 2023 10:02:10 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 856053002FC; Tue, 21 Mar 2023 11:02:06 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 694E420F030E2; Tue, 21 Mar 2023 11:02:06 +0100 (CET) Date: Tue, 21 Mar 2023 11:02:06 +0100 From: Peter Zijlstra To: Vincent Guittot Cc: mingo@redhat.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, linux-kernel@vger.kernel.org, zhangqiao22@huawei.com Subject: Re: [PATCH v2] sched/fair: sanitize vruntime of entity being migrated Message-ID: <20230321100206.GE2234901@hirez.programming.kicks-ass.net> References: <20230317160810.107988-1-vincent.guittot@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230317160810.107988-1-vincent.guittot@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 17, 2023 at 05:08:10PM +0100, Vincent Guittot wrote: > Commit 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed") > fixes an overflowing bug, but ignore a case that se->exec_start is reset > after a migration. > > For fixing this case, we delay the reset of se->exec_start after > placing the entity which se->exec_start to detect long sleeping task. > > In order to take into account a possible divergence between the clock_task > of 2 rqs, we increase the threshold to around 104 days. > > > Fixes: 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed") > Signed-off-by: Zhang Qiao > Signed-off-by: Vincent Guittot > --- Blergh, this just isn't going to be nice. I'll go queue this for sched/urgent and then we can forget about this for a little while. Thanks!