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=-13.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 AE7BAC433E3 for ; Mon, 27 Jul 2020 09:29:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0B0A206E7 for ; Mon, 27 Jul 2020 09:28:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=axis.com header.i=@axis.com header.b="TqTg7bkh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728089AbgG0J26 (ORCPT ); Mon, 27 Jul 2020 05:28:58 -0400 Received: from smtp2.axis.com ([195.60.68.18]:7630 "EHLO smtp2.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726139AbgG0J25 (ORCPT ); Mon, 27 Jul 2020 05:28:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; l=1110; q=dns/txt; s=axis-central1; t=1595842137; x=1627378137; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=LDGMiNDyHEEpsPh7ha2tAju2Qa0XvBjPxQymomgNiZU=; b=TqTg7bkhR+PqETWVSxuQSXyVt0r3xPSF9Ul65CZIUgCW51/JcChQB6WO /+2D7lkoBtgkOfeRfmqfhT4Xm+v3aeBykBlhe31exacC+6Gv5HLrwtMw+ TNUeND8fBbJpA4pehYDsVaLCVV6yMp7LN0hhcI1d9pAq+H7vLKoU/JBvR 1aQmSPhN6VGbU4Il+Zvo6uSgP+cDFTRR8E6GWdQHPDo8mVc7FKXEuXjb3 qz86EFEZG7WOD4gxnwLJptjLcsTcInwxYWHingvx3RFcNLvCFhkLxA47C FHeKayKOBRYmRlKRhRfVyad7ctS8XYahK/gRL/1ZPn2O7vy41cJqvYpOI A==; IronPort-SDR: 6H1P+HoGSEAeLwpLTlTr0VvQFeuXjp8ZiRVbfqpCucp2qs7Y3oONw1sIApR7+BuqX59LlHKR6Z v2/Dx9AV0YivCd+WqOn80QKd+MiCGOMCYf8xC1ZyKNp0DMJvE1IvU4tYfVw9F6XS+RZcBP8ma5 +41Lyuo0alSXbXx9zNM2sk8bw1OGJ6wer4b0QwH2q41UXBKyEDyzEXwUDzwoVokL0OrKgodMqB JA2AkAOtYcD6LLa4T37ALsr/BbkUzpUps+5aN48/RRb9stWj+tYd9kIw3bCuzxRFau+DVgvtnw 0jo= X-IronPort-AV: E=Sophos;i="5.75,402,1589234400"; d="scan'208";a="10911943" From: Vincent Whitchurch To: Steven Rostedt , Ingo Molnar CC: , , Vincent Whitchurch , Subject: [PATCH] tracing: Remove outdated comment in stack handling Date: Mon, 27 Jul 2020 11:28:40 +0200 Message-ID: <20200727092840.18659-1-vincent.whitchurch@axis.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This comment describes the behaviour before commit 2a820bf74918 ("tracing: Use percpu stack trace buffer more intelligently"). Since that commit, interrupts and NMIs do use the per-cpu stacks so the comment is no longer correct. Remove it. (Note that the FTRACE_STACK_SIZE mentioned in the comment has never existed, it probably should have said FTRACE_STACK_ENTRIES.) Signed-off-by: Vincent Whitchurch --- kernel/trace/trace.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index bb62269724d5..0a0fd197888c 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2932,12 +2932,6 @@ static void __ftrace_trace_stack(struct trace_buffer *buffer, skip++; #endif - /* - * Since events can happen in NMIs there's no safe way to - * use the per cpu ftrace_stacks. We reserve it and if an interrupt - * or NMI comes in, it will just have to use the default - * FTRACE_STACK_SIZE. - */ preempt_disable_notrace(); stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1; -- 2.25.1