From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753024AbbE0PGc (ORCPT ); Wed, 27 May 2015 11:06:32 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:32790 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751558AbbE0PG1 (ORCPT ); Wed, 27 May 2015 11:06:27 -0400 Message-ID: <4da368f6f34fc07eff97ddc3dfbced2c.squirrel@www.codeaurora.org> In-Reply-To: <5565056D.4050200@codeaurora.org> References: <1432683555-4644-1-git-send-email-ankgupta@codeaurora.org> <5565056D.4050200@codeaurora.org> Date: Wed, 27 May 2015 09:06:22 -0600 Subject: Re: [PATCH] spmi-pmic-arb: add irq tracepoints to the pmic-arb driver From: "Ankit Gupta" To: "Stephen Boyd" Cc: "Ankit Gupta" , gavidov@codeaurora.org, sdharia@codeaurora.org, ivan.ivanov@linaro.org, svarbanov@mm-sol.com, rostedt@goodmis.org, linux-arm-msm@vger.kernel.org, gregkh@linuxfoundation.org, collinsd@codeaurora.org, osvaldob@codeaurora.org, linux-kernel@vger.kernel.org, mlocke@codeaurora.org, galak@codeaurora.org, agross@codeaurora.org User-Agent: SquirrelMail/1.4.22-4.el6 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Priority: 3 (Normal) Importance: Normal Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On 05/26/2015 04:39 PM, Ankit Gupta wrote: >> The spmi-pmic-arb is also an interrupt controller. It gets a >> single aggregate irq and disseminates it to individual >> pmic-peripheral drivers. Each pmic-peripheral has a unique apid >> number, and can have multiple interrupt capable functions. >> The registered apid range shows the lowest and highest apid >> numbers of pmic-peripheral drivers which request irqs. Pid is >> the base address of that peripheral. For performance measurement, >> tracepoints are added at the beginning of the aggregate irq and >> at the end of the individual pmic-peripheral irqs. >> >> Following is a list showing the new tracepoint events: >> >> spmi_pmic_arb_aggregate_irq_start: aggregate irq number and registered >> apid range. >> >> spmi_pmic_arb_apid_irq_end: apid, irq, func_num, sid and pid. >> >> SPMI Interrupts tracepoints can be enabled like: >> >> echo 1 >/sys/kernel/debug/tracing/events/spmi-pmic-arb/enable >> >> and will dump messages that can be viewed in >> /sys/kernel/debug/tracing/trace that look like: >> ... spmi_pmic_arb_aggregate_irq_start: irq=150 registered apid >> range=(3,189) >> ... spmi_pmic_arb_apid_irq_end: apid=3 irq=1 func_num=0 sid=0 pid=0x8 >> >> Suggested-by: Sagar Dharia >> Signed-off-by: Gilad Avidov >> Signed-off-by: Ankit Gupta >> --- > > How is this any better than irq tracepoints that we already have for > generic irqs? > It is better than generic irq tracepoints because it provides bus specific information (sid and address(pid) of slave write), driver specific information (apid (pmic-peripheral) and func_num) and statistics (apid range). Recall that *slave* read/write cannot be traced by the spmi framework ftrace. > -- > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, > a Linux Foundation Collaborative Project > >