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 X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D46AAC49361 for ; Mon, 28 Jun 2021 15:21:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C008561949 for ; Mon, 28 Jun 2021 15:21:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237913AbhF1PXs (ORCPT ); Mon, 28 Jun 2021 11:23:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:37106 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236478AbhF1PAM (ORCPT ); Mon, 28 Jun 2021 11:00:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id CC60D61D61; Mon, 28 Jun 2021 14:40:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624891246; bh=t6L9j0lOhpSCsIRzBJNCm+dDScW9tSN830gCfIZO8d4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nxBmtMy/VonbMrJx9emt0H5ZFtob4voMIXZ7PMXvxpoU53+SleBKAXdKaPUb4LWxa mWwhlf/EdWSedIDhcn+Md5dYSM4weTBt4vqzqvnkJ7NigJcYoRn0nllcNYvHvgmace OPCqEIXE+hwfiTAbK5ljg/k6f3f1DzJSBu4f4Mk8VJ4lYfhcv6P+ds/oYsxqN2g8eX pI6c563/CkxwMPDQH9U4qqm9FzFeIs1pvhb2wlYOIzMeov2+0Z5mC2trbXr43VSw+V enYk9HX5wNOWq09v/WBgsZRTQ7mEe52RMJUa7qE1PN+U+zMDD8HpIpYUfHi9vd/dQK ZyCjW3i+cHz4w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Steven Rostedt (VMware)" , Greg Kroah-Hartman Subject: [PATCH 4.9 47/71] tracing: Do not stop recording cmdlines when tracing is off Date: Mon, 28 Jun 2021 10:39:39 -0400 Message-Id: <20210628144003.34260-48-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210628144003.34260-1-sashal@kernel.org> References: <20210628144003.34260-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.274-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-4.9.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 4.9.274-rc1 X-KernelTest-Deadline: 2021-06-30T14:39+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Steven Rostedt (VMware)" commit 85550c83da421fb12dc1816c45012e1e638d2b38 upstream. The saved_cmdlines is used to map pids to the task name, such that the output of the tracing does not just show pids, but also gives a human readable name for the task. If the name is not mapped, the output looks like this: <...>-1316 [005] ...2 132.044039: ... Instead of this: gnome-shell-1316 [005] ...2 132.044039: ... The names are updated when tracing is running, but are skipped if tracing is stopped. Unfortunately, this stops the recording of the names if the top level tracer is stopped, and not if there's other tracers active. The recording of a name only happens when a new event is written into a ring buffer, so there is no need to test if tracing is on or not. If tracing is off, then no event is written and no need to test if tracing is off or not. Remove the check, as it hides the names of tasks for events in the instance buffers. Cc: stable@vger.kernel.org Fixes: 7ffbd48d5cab2 ("tracing: Cache comms only after an event occurred") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index cdf614943aa3..74ec372a3286 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1882,9 +1882,6 @@ void trace_find_cmdline(int pid, char comm[]) void tracing_record_cmdline(struct task_struct *tsk) { - if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) - return; - if (!__this_cpu_read(trace_cmdline_save)) return; -- 2.30.2