From patchwork Sun Jul 10 08:50:27 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Rabin Vincent X-Patchwork-Id: 104050 Return-Path: X-Original-To: incoming-imx@patchwork.ozlabs.org Delivered-To: patchwork-incoming-imx@bilbo.ozlabs.org Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 998F7B71CD for ; Sun, 10 Jul 2011 18:51:27 +1000 (EST) Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QfpjS-0005PS-C6; Sun, 10 Jul 2011 08:51:18 +0000 Received: from localhost ([127.0.0.1] helo=canuck.infradead.org) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QfpjS-0002Us-08; Sun, 10 Jul 2011 08:51:18 +0000 Received: from mail-bw0-f49.google.com ([209.85.214.49]) by canuck.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QfpjN-0002UY-V1 for linux-arm-kernel@lists.infradead.org; Sun, 10 Jul 2011 08:51:15 +0000 Received: by bwf12 with SMTP id 12so3175696bwf.36 for ; Sun, 10 Jul 2011 01:51:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type :content-transfer-encoding; bh=6t2pubuSz/YMvz+wqRUfOHhqQP7KRxn0Ypxx/+VfX7g=; b=QMeOEYbaAjSW1DCPz5F+HTH4iC8XQKWzm2PSXkgGICNB1aXMQFnKHR5lCx6PiqLmr5 J/qim96l8lhMgbhDAnw30b/Ja5mAlJ8vh4ZA++lV6O3ITMAAn9PPJ2uAvXPlB1J1Yp2T P2lUSkj+BS9CdvqMCqbzfuIpHF2boTuIt4UjE= Received: by 10.204.190.80 with SMTP id dh16mr975891bkb.334.1310287867500; Sun, 10 Jul 2011 01:51:07 -0700 (PDT) MIME-Version: 1.0 Received: by 10.204.101.212 with HTTP; Sun, 10 Jul 2011 01:50:27 -0700 (PDT) In-Reply-To: <201107041909.27354.tim.sander@hbm.com> References: <201107041909.27354.tim.sander@hbm.com> From: Rabin Vincent Date: Sun, 10 Jul 2011 14:20:27 +0530 X-Google-Sender-Auth: eQBOWtUONkLl9V5vHfHX4VKi1ec Message-ID: Subject: Re: function tracer on i.mx35 (pcm043) To: Tim Sander X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.6 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20110710_045114_251350_4816648D X-CRM114-Status: GOOD ( 15.23 ) X-Spam-Score: -0.7 (/) X-Spam-Report: SpamAssassin version 3.3.1 on canuck.infradead.org summary: Content analysis details: (-0.7 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [209.85.214.49 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (rabin.vincent[at]gmail.com) 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature Cc: linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.12 Precedence: list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+incoming-imx=patchwork.ozlabs.org@lists.infradead.org List-Id: linux-imx-kernel.lists.patchwork.ozlabs.org On Mon, Jul 4, 2011 at 22:39, Tim Sander wrote: > Using vanilla 2.6.39 on arm i.mx35 (pcm043) with trace-cmd 1.0.5, > build with: > arm-1136jfs-linux-gnueabi-gcc (OSELAS.Toolchain-2011.03.0) 4.5.2. > > I am currently trying to find the reason why the irq on the i.mx35 is somtimes > up do 80µs delayed. I thought that the function tracer would help in solving > that problem but unfortunately it crashes when using the function trace plugin. I think your platform uses arch/arm/plat-mxc/time.c? Oopses with the function graph tracer are usually caused by recursion due to a missing notrace annotation on sched_clock() or its called functions. Could you please try the following change? (applies on 2.6.39) diff --git a/arch/arm/plat-mxc/time.c b/arch/arm/plat-mxc/time.c index 2237ff8..9c7c6dc 100644 --- a/arch/arm/plat-mxc/time.c +++ b/arch/arm/plat-mxc/time.c @@ -106,17 +106,17 @@ static void gpt_irq_acknowledge(void) __raw_writel(V2_TSTAT_OF1, timer_base + V2_TSTAT); } -static cycle_t dummy_get_cycles(struct clocksource *cs) +static cycle_t notrace dummy_get_cycles(struct clocksource *cs) { return 0; } -static cycle_t mx1_2_get_cycles(struct clocksource *cs) +static cycle_t notrace mx1_2_get_cycles(struct clocksource *cs) { return __raw_readl(timer_base + MX1_2_TCN); } -static cycle_t v2_get_cycles(struct clocksource *cs) +static cycle_t notrace v2_get_cycles(struct clocksource *cs) { return __raw_readl(timer_base + V2_TCN); }