From patchwork Tue Jun 20 01:31:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheng Yejian X-Patchwork-Id: 110033 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp3038481vqr; Mon, 19 Jun 2023 07:16:43 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ62JQMNfHS2i491cDIo9qJXSXK/fyxE+mhjWyfRgZP89B8MVKiz1d0PLuzz3PQsh7JNRCTf X-Received: by 2002:a17:902:ead2:b0:1b0:5304:5b48 with SMTP id p18-20020a170902ead200b001b053045b48mr9727823pld.0.1687184202940; Mon, 19 Jun 2023 07:16:42 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1687184202; cv=none; d=google.com; s=arc-20160816; b=VXgtP0WH1bjj+RIavzbuH2yY/IR/Q1UVGwZKAcr6z0/iVbvwxdbMSGxaYCyctnhQru kGUgcqOIwlV6zBwnUg2fJd0Bbj8BR9THzawPnFzxGOuKZWs3ECKHNGljgws/0st7+ET7 pHSd2mgZRmK2SFOjfuu8/YEju4N0GhYEnqJnMcwlupGbmWFIh0T6Y3zyu9F8xuHpglf9 i6WuRC+o/Xia8/w+j8ksOrumbDhd6sFp4b56AOr48ZvnXqHx+v04gPGFAHemSY1gR3v3 poT+FES2pEMKnNxQMGt7O0ql0rmDuUukSgnQxFtXegJ3rpNf0WH0KG6TVQ3RyvV0SKLN ruXw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from; bh=OxRas6VvQNX5j7j2awXcaInid26I+3e57zkmbFI8VH8=; b=eWtFSHMOVjSyr6sGvfgY0P+aE3C68KHWJwLz9KK13+xcf9iQfuS4M7ynaEzBtf3Wy2 Qkhf0zUc/2jXFSwfUhuSllM6VF/Us2zuc2rY2QTBs5dSLFnZPrOCI2/+xRrhjdbFE9aE +BvLO3kwRbkZDbi8px9loDxuXSfL72hpre5qm/ir5Eyaa9XSQuzokVm6DyQPGJT2ezrO ySlel7vvuRcvC/e5s6mIWbrCujuRmu4GlTnMyKf/xoK+AHB6O/19GCll0wkp9t14AdV8 1HES8mPeaCrp7ZaCLSN/OwBb5VsiLazI8srzqNnhqtqJthFsj4iECyhnIYhCa+CcR0qG vLaQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=huawei.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id i17-20020a170902c95100b001b3b250fd1csi1332677pla.301.2023.06.19.07.16.26; Mon, 19 Jun 2023 07:16:42 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=huawei.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231961AbjFSNbH (ORCPT + 99 others); Mon, 19 Jun 2023 09:31:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36876 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229875AbjFSNaz (ORCPT ); Mon, 19 Jun 2023 09:30:55 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4196BE66; Mon, 19 Jun 2023 06:30:54 -0700 (PDT) Received: from dggpeml500012.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Ql9d15Zgmz1GD5Y; Mon, 19 Jun 2023 21:30:45 +0800 (CST) Received: from localhost.localdomain (10.67.175.61) by dggpeml500012.china.huawei.com (7.185.36.15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Mon, 19 Jun 2023 21:30:50 +0800 From: Zheng Yejian To: , , CC: , , , Subject: [PATCH 5.10] tracing: Add tracing_reset_all_online_cpus_unlocked() function Date: Tue, 20 Jun 2023 09:31:04 +0800 Message-ID: <20230620013104.1127100-1-zhengyejian1@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.67.175.61] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpeml500012.china.huawei.com (7.185.36.15) X-CFilter-Loop: Reflected X-Spam-Status: No, score=-1.0 required=5.0 tests=BAYES_00,DATE_IN_FUTURE_12_24, RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1769138784829861750?= X-GMAIL-MSGID: =?utf-8?q?1769140862894134194?= From: "Steven Rostedt (Google)" commit e18eb8783ec4949adebc7d7b0fdb65f65bfeefd9 upstream. Currently the tracing_reset_all_online_cpus() requires the trace_types_lock held. But only one caller of this function actually has that lock held before calling it, and the other just takes the lock so that it can call it. More users of this function is needed where the lock is not held. Add a tracing_reset_all_online_cpus_unlocked() function for the one use case that calls it without being held, and also add a lockdep_assert to make sure it is held when called. Then have tracing_reset_all_online_cpus() take the lock internally, such that callers do not need to worry about taking it. Link: https://lkml.kernel.org/r/20221123192741.658273220@goodmis.org Cc: Masami Hiramatsu Cc: Andrew Morton Cc: Zheng Yejian Signed-off-by: Steven Rostedt (Google) [Refers to commit message of be111ebd8868d4b7c041cb3c6102e1ae27d6dc1d, this patch is pre-depended, and tracing_reset_all_online_cpus() should be called after trace_types_lock is held as its comment describes.] Fixes: be111ebd8868 ("tracing: Free buffers when a used dynamic event is removed") Signed-off-by: Zheng Yejian --- kernel/trace/trace.c | 11 ++++++++++- kernel/trace/trace.h | 1 + kernel/trace/trace_events.c | 2 +- kernel/trace/trace_events_synth.c | 2 -- 4 files changed, 12 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 482ec6606b7b..70526400e05c 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2178,10 +2178,12 @@ void tracing_reset_online_cpus(struct array_buffer *buf) } /* Must have trace_types_lock held */ -void tracing_reset_all_online_cpus(void) +void tracing_reset_all_online_cpus_unlocked(void) { struct trace_array *tr; + lockdep_assert_held(&trace_types_lock); + list_for_each_entry(tr, &ftrace_trace_arrays, list) { if (!tr->clear_trace) continue; @@ -2193,6 +2195,13 @@ void tracing_reset_all_online_cpus(void) } } +void tracing_reset_all_online_cpus(void) +{ + mutex_lock(&trace_types_lock); + tracing_reset_all_online_cpus_unlocked(); + mutex_unlock(&trace_types_lock); +} + /* * The tgid_map array maps from pid to tgid; i.e. the value stored at index i * is the tgid last observed corresponding to pid=i. diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 37f616bf5fa9..e5b505b5b7d0 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -725,6 +725,7 @@ int tracing_is_enabled(void); void tracing_reset_online_cpus(struct array_buffer *buf); void tracing_reset_current(int cpu); void tracing_reset_all_online_cpus(void); +void tracing_reset_all_online_cpus_unlocked(void); int tracing_open_generic(struct inode *inode, struct file *filp); int tracing_open_generic_tr(struct inode *inode, struct file *filp); bool tracing_is_disabled(void); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index bac13f24a96e..f8ed66f38175 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2661,7 +2661,7 @@ static void trace_module_remove_events(struct module *mod) * over from this module may be passed to the new module events and * unexpected results may occur. */ - tracing_reset_all_online_cpus(); + tracing_reset_all_online_cpus_unlocked(); } static int trace_module_notify(struct notifier_block *self, diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 18291ab35657..ee174de0b8f6 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -1363,7 +1363,6 @@ int synth_event_delete(const char *event_name) mutex_unlock(&event_mutex); if (mod) { - mutex_lock(&trace_types_lock); /* * It is safest to reset the ring buffer if the module * being unloaded registered any events that were @@ -1375,7 +1374,6 @@ int synth_event_delete(const char *event_name) * occur. */ tracing_reset_all_online_cpus(); - mutex_unlock(&trace_types_lock); } return ret;