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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS 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 75C87C43381 for ; Tue, 5 Mar 2019 00:02:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4173A2070B for ; Tue, 5 Mar 2019 00:02:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551744155; bh=Ux8/YbJjP9yh30Q8QH+q7zD0Qdj3rgun+Bf6UGmdC+U=; h=Subject:From:To:Cc:Date:In-Reply-To:References:List-ID:From; b=JW1wWydcY4b7C3k3HDdNOsCEgSbrpHUkRlC66dhCX2PaCSh2lw0LeAT2CE94kow2a 7R4P+jaamer/gxfW1MkscucPHltBD1xCR9HDgPWcDNu0ONkDcCiDxovEPzHgslHgXR aeUvXUTiq3mrnMT+ZmEAo5/MsR1GRMyi0nftzTEY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726820AbfCEACa (ORCPT ); Mon, 4 Mar 2019 19:02:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:49232 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726716AbfCEAC3 (ORCPT ); Mon, 4 Mar 2019 19:02:29 -0500 Received: from tzanussi-mobl (c-98-220-238-81.hsd1.il.comcast.net [98.220.238.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A994E206B8; Tue, 5 Mar 2019 00:02:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551744149; bh=Ux8/YbJjP9yh30Q8QH+q7zD0Qdj3rgun+Bf6UGmdC+U=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=FQtzdd+mnLuMe3A/bTRJFCG+rIo2z0HbPd/PWsHPeICKRjVjtK3xwJkgwhvgagOhu jLxiVxd7ZfmyW5G7GrtggWtZ+90SN3nIXVcudFCjZwt3fz06rntU4VTTo8bfh3BXq4 f11YYUhb6h8piFeX6LM9wxnkAfESNu51W9/VWHtQ= Message-ID: <1551744147.3771.0.camel@kernel.org> Subject: Re: [PATCH 2/2] tracing: Use strncpy instead of memcpy for string keys in hist triggers From: Tom Zanussi To: Steven Rostedt , Tom Zanussi Cc: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, Namhyung Kim Date: Mon, 04 Mar 2019 18:02:27 -0600 In-Reply-To: <20190304184530.7e819698@gandalf.local.home> References: <50c35ae1267d64eee975b8125e151e600071d4dc.1549309756.git.tom.zanussi@linux.intel.com> <20190304165000.0ce0fbdd@gandalf.local.home> <20190304165653.17699f9f@gandalf.local.home> <5643a1971831ce2d01a947f0f07cefa002bbdc25.camel@linux.intel.com> <5c978b4b0d629e5a914c512c14f99f6a24241407.camel@linux.intel.com> <20190304184530.7e819698@gandalf.local.home> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.1-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-rt-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org On Mon, 2019-03-04 at 18:45 -0500, Steven Rostedt wrote: > On Mon, 04 Mar 2019 16:31:40 -0600 > Tom Zanussi wrote: > > > > Hmm, I don't think it's really necessary - it's not used in a key > > > so > > > don't care about anything after the null, and TASK_COMM_LEN is > > > used > > > in > > > the memcpy. > > > > Never mind, yeah, it would make sense to do this, will create > > another > > patch... > > And probably should change the memcpy() of comm in > kernel/trace/trace.c > too. It could be that memcpy() is a little bit faster than strncpy(), > and this is done on scheduling switches when tracing is active, but > still, I'm starting to think that isn't a good choice. > OK, will add that too. Tom > -- Steve