From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gilad Avidov Subject: Re: [PATCH] spmi-pmic-arb: add irq tracepoints to the pmic-arb driver Date: Fri, 29 May 2015 13:56:04 -0600 Message-ID: <20150529135604.541eee30@gavidov-lnx.qualcomm.com> References: <1432683555-4644-1-git-send-email-ankgupta@codeaurora.org> <5565056D.4050200@codeaurora.org> <4da368f6f34fc07eff97ddc3dfbced2c.squirrel@www.codeaurora.org> <20150527200629.GB24204@codeaurora.org> <20150528170250.16027406@gavidov-lnx.qualcomm.com> <5567BDCF.6030709@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:54995 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752094AbbE2T4K (ORCPT ); Fri, 29 May 2015 15:56:10 -0400 In-Reply-To: <5567BDCF.6030709@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Stephen Boyd Cc: Ankit Gupta , 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 On Thu, 28 May 2015 18:15:59 -0700 Stephen Boyd wrote: > On 05/28/2015 04:02 PM, Gilad Avidov wrote: > > On Wed, 27 May 2015 13:06:29 -0700 > > Stephen Boyd wrote: > > > >> On 05/27, Ankit Gupta wrote: > >>>> 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. > >>> > >> Don't we already get all this information based on how we map > >> interrupts to devices in DT? It feels to me that the same > >> argument here could be applied to all the random gpio expanders > >> and chained interrupt controllers that we support in the kernel. > >> > > We don't. > > We could get the same information if we had the irq-domain and > > hw-irq 32bit value. While these values are available > > from /proc/interrupt, they are not available from the irq event > > tracing. > > Hm.. maybe we should add those trace events then into the irq domain > layer? Or even extend the irq tracepoints to include the hw-irq and > irq-domain name? > I agree, adding hw-irq and irq-domain name to irq-tracing is a better idea. > > > > This patch traces spmi slave-originated events. If we had one such > > slave we could cross information from both sources to filter the > > trace events. However, we have hundreds of transaction-capable spmi > > slaves. > > > > Sorry I'm not following this point. If it was about tracing > slave-originated events wouldn't it be more than irqs then? > Slave originated events are converted to irqs by the spmi controller. Thanks, Gilad