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 B99EBC433F5 for ; Sat, 23 Apr 2022 03:05:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232339AbiDWDIi (ORCPT ); Fri, 22 Apr 2022 23:08:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232288AbiDWDIg (ORCPT ); Fri, 22 Apr 2022 23:08:36 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A46F8E4B; Fri, 22 Apr 2022 20:05:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=SxQi15J/S+m7GUVDTi1JQZIeFqsLLWQuUAEkCr4fpr0=; b=JfuO39DnJIvtdTBrO8b1kB7hWJ UyHWEcNq2XEKydIC8o31W4QfkrZmYTLJoM/PeeMXAHmbr4FI39u87nAEHE91J5KuyvjH5r1jssYyn bKI0X3DDf7nvRoeWmRbbdaHfIzm1kClBBVuio8U3hfhQWnNbuc+X4IYIwiCF6W/qVwVQhtCRPGyqE yj2TH/MPjJLDNt5u/7ZKqG/TMzFofvxXMPBty+ChmVxDu5IXB39cYAgKj47aq/K3KHnYQtyIfacPW 9diNSl5ba6pjjbCSPx1ohzPlmXtiq79SE28x0iCfDSfBjLAfsfddyOLOLDLvjNjIwsx1AeGUXqTXI UsqJoqbw==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1ni65S-006f4j-Hf; Sat, 23 Apr 2022 03:05:30 +0000 Date: Sat, 23 Apr 2022 04:05:30 +0100 From: Matthew Wilcox To: Junwen Wu Cc: akpm@linux-foundation.org, keescook@chromium.org, adobriyan@gmail.com, fweimer@redhat.com, ddiss@suse.de, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v1] proc: limit schedstate node write operation Message-ID: References: <20220423023104.153004-1-wudaemon@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220423023104.153004-1-wudaemon@163.com> Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Sat, Apr 23, 2022 at 02:31:04AM +0000, Junwen Wu wrote: > Whatever value is written to /proc/$pid/sched, a task's schedstate data > will reset.In some cases, schedstate will drop by accident. We restrict > writing a certain value to this node before the data is reset. ... and break the existing scripts which expect the current behaviour. 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 30FD6C433FE for ; Sun, 24 Apr 2022 15:35:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233428AbiDXPiA (ORCPT ); Sun, 24 Apr 2022 11:38:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240198AbiDXP2p (ORCPT ); Sun, 24 Apr 2022 11:28:45 -0400 Received: from m12-16.163.com (m12-16.163.com [220.181.12.16]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 502C3186F0; Sun, 24 Apr 2022 08:25:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=SSwEb R1Q0zSkY2pkp2ZsB1ndiNG5yqAkeTuM/roPQF8=; b=hPyVegbjX0JylMYh/e+HX IS+ahqmgjqBBm3IzNIva1SPiyQvhX/4uvc5lC8MeFzN4p5beKIW23HqerLPeB6oE 6gtvtrZFCsjBx1ss/mPNFAxzBa+RkwO0/NLdv6sM+RYMIHsGidfaoV3L5w+m9HBO 6a8Cv0TKCzZ1OULa4sgnks= Received: from localhost (unknown [113.116.51.137]) by smtp12 (Coremail) with SMTP id EMCowAC3kXW4a2ViEoBPBQ--.1532S2; Sun, 24 Apr 2022 23:24:41 +0800 (CST) From: Junwen Wu To: willy@infradead.org, Junwen Wu Cc: adobriyan@gmail.com, akpm@linux-foundation.org, ddiss@suse.de, fweimer@redhat.com, keescook@chromium.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] proc: limit schedstate node write operation Date: Sun, 24 Apr 2022 15:23:54 +0000 Message-ID: (raw) X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220423023104.153004-1-wudaemon@163.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: EMCowAC3kXW4a2ViEoBPBQ--.1532S2 X-Coremail-Antispam: 1Uf129KBjDUn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7v73 VFW2AGmfu7bjvjm3AaLaJ3UbIYCTnIWIevJa73UjIFyTuYvjTRJ8neDUUUU X-Originating-IP: [113.116.51.137] X-CM-SenderInfo: 5zxgtvxprqqiywtou0bp/xtbBFArrbVaEDhGxwgABsn Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Message-ID: <20220424152354.YvP810z4DjdXxXspWzCdwUz-SQHILZydxFs4QMGuHqI@z> From: Matthew Wilcox On Sat, Apr 23, 2022 at 02:31:04AM +0000, Junwen Wu wrote: > Whatever value is written to /proc/$pid/sched, a task's schedstate data > will reset.In some cases, schedstate will drop by accident. We restrict > writing a certain value to this node before the data is reset. ... and break the existing scripts which expect the current behaviour. Hi, Matthew,can you describe it in more detail. Thanks