From patchwork Fri Mar 10 10:04:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tero Kristo X-Patchwork-Id: 13169078 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 3A5E2C6FD1C for ; Fri, 10 Mar 2023 10:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231154AbjCJKFJ (ORCPT ); Fri, 10 Mar 2023 05:05:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229977AbjCJKFI (ORCPT ); Fri, 10 Mar 2023 05:05:08 -0500 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A6DD108C19; Fri, 10 Mar 2023 02:05:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1678442705; x=1709978705; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=uQwh0qZU4TAZ+z99KsgG//ut2821Ahj0nz8hE5A6nek=; b=DY6gnc4MtissJFkioEUWe9mIbhpqhJSo6XGxxNLv+dCcTxgLQ2NNOI3v 2AyORrYQGP0KYzmJefzACDAE5lPaxYm3hm4TDlHT5h94Q4jvbtqoCBe5P fuVyAfJfoMOuG0a7uhA5SqmXlxX04OK0ugV8f1cuVDLXNtW9ct3W9Uhkk lp4HbuurOHp+ChI6p2o9XJwJaVgaWYG+7b4Da0s/dNryYNagxNhDf19XG OkkofgngikDLknD8EMPgFzn/xFffPQFCm19GfzI68Ui3FfAZImxEJVUvd lvLxjv+20GOB/vMnKlXfqtXNdeO+1bjo2+NT7R5hgBGO7uQYByBy5Ky/n A==; X-IronPort-AV: E=McAfee;i="6500,9779,10644"; a="399294167" X-IronPort-AV: E=Sophos;i="5.98,249,1673942400"; d="scan'208";a="399294167" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2023 02:05:04 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10644"; a="923609300" X-IronPort-AV: E=Sophos;i="5.98,249,1673942400"; d="scan'208";a="923609300" Received: from fliu-mobl.ger.corp.intel.com (HELO tkristo-desk.intel.com) ([10.252.32.249]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2023 02:05:02 -0800 From: Tero Kristo To: rostedt@goodmis.org, bristot@kernel.org, mhiramat@kernel.org Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCHv2 1/2] trace/hwlat: Do not wipe the contents of per-cpu thread data Date: Fri, 10 Mar 2023 12:04:50 +0200 Message-Id: <20230310100451.3948583-2-tero.kristo@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230310100451.3948583-1-tero.kristo@linux.intel.com> References: <20230310100451.3948583-1-tero.kristo@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org Do not wipe the contents of the per-cpu kthread data when starting the tracer, as this will completely forget about already running instances and can later start new additional per-cpu threads. Signed-off-by: Tero Kristo Acked-by: Daniel Bristot de Oliveira --- v2: * split into separate patch kernel/trace/trace_hwlat.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c index d440ddd5fd8b..edc26dc22c3f 100644 --- a/kernel/trace/trace_hwlat.c +++ b/kernel/trace/trace_hwlat.c @@ -584,9 +584,6 @@ static int start_per_cpu_kthreads(struct trace_array *tr) */ cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask); - for_each_online_cpu(cpu) - per_cpu(hwlat_per_cpu_data, cpu).kthread = NULL; - for_each_cpu(cpu, current_mask) { retval = start_cpu_kthread(cpu); if (retval)