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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1135CC5AD4C for ; Thu, 23 Nov 2023 11:21:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7B8658D0022; Thu, 23 Nov 2023 06:21:44 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7684E8D0002; Thu, 23 Nov 2023 06:21:44 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 62FB18D0022; Thu, 23 Nov 2023 06:21:44 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 546A98D0002 for ; Thu, 23 Nov 2023 06:21:44 -0500 (EST) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 18FB6C072F for ; Thu, 23 Nov 2023 11:21:44 +0000 (UTC) X-FDA: 81488978928.06.97B09CE Received: from mx1.sberdevices.ru (mx2.sberdevices.ru [45.89.224.132]) by imf30.hostedemail.com (Postfix) with ESMTP id 77DED80013 for ; Thu, 23 Nov 2023 11:21:40 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=salutedevices.com header.s=mail header.b=gCrG99tM; spf=pass (imf30.hostedemail.com: domain of ddrokosov@salutedevices.com designates 45.89.224.132 as permitted sender) smtp.mailfrom=ddrokosov@salutedevices.com; dmarc=pass (policy=quarantine) header.from=salutedevices.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1700738501; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Vn+apVzXsEM6pqvtCgpqeXfkP+wK1W/P560NUnnIQWw=; b=SUqEwhagf4c+ebeiguQfeUA6CpVFFN2CB76wuobBRWdRaOG9kObCBNBBwfe2IuwFzB5msP Wsvc0nDSD2NST3baUt5gkdsULPULM0KIpM7omc4lt9E7To59j0WACa+Ye8bmEnFO1vFmAB C6XvbKjAsccBGLsGb00wwOFZN8h9uIw= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1700738501; a=rsa-sha256; cv=none; b=SxQJ1/LxMr8HRzxokm5WC0whoAvjAFau/9jGcBK8kZAh8GYpq/ZIta7JKSxwfzBiWEm+xX dhRGsiyOGFafVhnlr+tY1Y5uIB1AndLz9k8iyTkzgDv0V02+cWJ0UUUHPo5FFljctEp7Lh eaCwhmGdz6RLCpH2VP8cV6rSGWyHgKo= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=salutedevices.com header.s=mail header.b=gCrG99tM; spf=pass (imf30.hostedemail.com: domain of ddrokosov@salutedevices.com designates 45.89.224.132 as permitted sender) smtp.mailfrom=ddrokosov@salutedevices.com; dmarc=pass (policy=quarantine) header.from=salutedevices.com Received: from p-infra-ksmg-sc-msk02 (localhost [127.0.0.1]) by mx1.sberdevices.ru (Postfix) with ESMTP id 5DABC120003; Thu, 23 Nov 2023 14:21:37 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.sberdevices.ru 5DABC120003 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=salutedevices.com; s=mail; t=1700738497; bh=Vn+apVzXsEM6pqvtCgpqeXfkP+wK1W/P560NUnnIQWw=; h=Date:From:To:Subject:Message-ID:MIME-Version:Content-Type:From; b=gCrG99tMe19Ma2XQZX1ZrXApT9lHM0RmaeJnK+ikOirwkyOLHbdW0T3SCq4RMakMz YTjh901E2O56zBcccytdOogebIZZqVtHZPxHkhRKLCvgje7gCky0Pqv6kQsx3EAH1s i9E2aCGP59MEwj5lNDzIa2EO+u6owlAOoJwSdCLtMJYYpWpTxXWY0a8euMGMBhXef1 J36qV8oONQzlLFd9wHo/LD0kE9Jq1hCZl/OsauD24GposE5t0uaLW63ymrd+4uSICA cb/DJ8cq2SQlYYC/rtV1cUh/iJTvPZ9PUwq6X8lppbaqf++BEh/B8pccZKKrYDkj9t lKyWHhsrXpC8Q== Received: from p-i-exch-sc-m01.sberdevices.ru (p-i-exch-sc-m01.sberdevices.ru [172.16.192.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.sberdevices.ru (Postfix) with ESMTPS; Thu, 23 Nov 2023 14:21:37 +0300 (MSK) Received: from localhost (100.64.160.123) by p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Thu, 23 Nov 2023 14:21:37 +0300 Date: Thu, 23 Nov 2023 14:21:36 +0300 From: Dmitry Rokosov To: Shakeel Butt CC: , , , , , , , , , , , , Subject: Re: [PATCH v2 1/2] mm: memcg: print out cgroup name in the memcg tracepoints Message-ID: <20231123112136.n7qgkevgrracuk7m@CAB-WSD-L081021> References: <20231122100156.6568-1-ddrokosov@salutedevices.com> <20231122100156.6568-2-ddrokosov@salutedevices.com> <20231123072126.jpukmc6rqmzckdw2@google.com> <20231123080334.5owfpg7zl4nzeh4t@CAB-WSD-L081021> <20231123081547.7fbxd4ts3qohrioq@google.com> <20231123084510.wwnkjyrrbp5vltkg@CAB-WSD-L081021> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20231123084510.wwnkjyrrbp5vltkg@CAB-WSD-L081021> User-Agent: NeoMutt/20220415 X-Originating-IP: [100.64.160.123] X-ClientProxiedBy: p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) To p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) X-KSMG-Rule-ID: 10 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Lua-Profiles: 181556 [Nov 23 2023] X-KSMG-AntiSpam-Version: 6.0.0.2 X-KSMG-AntiSpam-Envelope-From: ddrokosov@salutedevices.com X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Info: LuaCore: 3 0.3.3 e5c6a18a9a9bff0226d530c5b790210c0bd117c8, {Track_E25351}, {Tracking_from_domain_doesnt_match_to}, 127.0.0.199:7.1.2;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;p-i-exch-sc-m01.sberdevices.ru:7.1.1,5.0.1;salutedevices.com:7.1.1;100.64.160.123:7.1.2, FromAlignment: s, ApMailHostAddress: 100.64.160.123 X-MS-Exchange-Organization-SCL: -1 X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiPhishing: Clean X-KSMG-LinksScanning: Clean X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2023/11/23 09:18:00 #22508170 X-KSMG-AntiVirus-Status: Clean, skipped X-Stat-Signature: d7urjckrrwu6bmekwe6fxo9fqts8zyr3 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 77DED80013 X-Rspam-User: X-HE-Tag: 1700738500-989119 X-HE-Meta: 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 WvhYvayu t4bUE60c4LQQV6UliFJGpMEJos0RiSJ1V/AlB8A4EdZumV4HcHzO9OcLFgm8/sfGilByEYR5Hhl/vDoG7K29pbSQuVecnn7bh8KggboZas3A2hnsly+JO2hT5y5bj60n/lI9MyFPellDhgj1U0asOMGL1eboKTWO3HFhMdkfWHoqQj0LLIzq2FcngJVUSmVqLyfVDFN+svNzyvWfvLTUgTueYm+cqMpjRpKHgP3NFapISYn3dyRp8dKMATC0czb+KLLTB9/ezpsBuC22Z6kzbH+EkNndvcc3kvU9BPTPUlfc4eqTYLxZypGvufFuxZIhSmmut X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Shakeel, On Thu, Nov 23, 2023 at 11:45:10AM +0300, Dmitry Rokosov wrote: > On Thu, Nov 23, 2023 at 08:15:47AM +0000, Shakeel Butt wrote: > > On Thu, Nov 23, 2023 at 11:03:34AM +0300, Dmitry Rokosov wrote: > > [...] > > > > > + cgroup_name(memcg->css.cgroup, > > > > > + __entry->name, > > > > > + sizeof(__entry->name)); > > > > > > > > Any reason not to use cgroup_ino? cgroup_name may conflict and be > > > > ambiguous. > > > > > > I actually didn't consider it, as the cgroup name serves as a clear tag > > > for filtering the appropriate cgroup in the entire trace file. However, > > > you are correct that there might be conflicts with cgroup names. > > > Therefore, it might be better to display both tags: ino and name. What > > > do you think on this? > > > > > > > I can see putting cgroup name can avoid pre or post processing, so > > putting both are fine. Though keep in mind that cgroup_name acquires a > > lock which may impact the applications running on the system. > > Are you talking about kernfs_rename_lock? Yes, it's acquired each > time... Unfortunatelly, I don't know a way to save cgroup_name one time > somehow... I delved deeper and realized that kernfs_rename_lock is a read-write lock, but it's a global one. While it's true that we only enable tracepoints during specific periods of the host's lifetime, the trace system is still a fast way to debug things. So, you're absolutely right, we shouldn't slow down the system unnecessarily. Therefore, today I will prepare a new version with only the cgroup ino. Thank you for pointing that out to me! -- Thank you, Dmitry