From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH] tracing, perf: add more power related events Date: Tue, 28 Sep 2010 23:22:15 +0200 Message-ID: <201009282322.16291.rjw__22749.6395390064$1285709068$gmane$org@sisk.pl> References: <201009222049.18154.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Jean Pihet Cc: Len Brown , linux-trace-users@vger.kernel.org, Peter Zijlstra , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-pm@lists.linux-foundation.org, Ingo Molnar , linux-omap@vger.kernel.org, Arjan van de Ven , arjan@infradead.org List-Id: linux-pm@vger.kernel.org On Tuesday, September 28, 2010, Jean Pihet wrote: > Hi, Hi, > Here is what I am proposing, in reply to all your comments: > > 1) rename the events to match Thomas's proposal: > power:power_cpu_cstate > power:power_cpu_pstate > power:power_cpu_sstate If that sstate thing is going to mean "suspend", then please drop it. "Suspend" is not a state, let alone a CPU state. It is a procedure by which the (entire) system is put into a sleep state (that is not confined to CPUs). > ... > > 2) introduce a new Kconfig option CONFIG_DEPRECATED_POWER_EVENTS and > conditionally map a subset of the new events to the old ones for > backward compatibility with the existing user apps. The apps should be > converted to the new API asap, > > 3) update documentation Sounds reasonable. > Other remarks here below: > > On Wed, Sep 22, 2010 at 8:49 PM, Rafael J. Wysocki wrote: > ... > > This POWER_SSTATE thing seems to be totally artificial and omap-specific. > > > > Why do you want it to be done this way? > > > > Or is the ACPI handling added in the ACPI patch? In which case, why don't you > > put that power_switch_state(POWER_SSTATE, 1, 0, cpu) into > > kernel/power/suspend.c:suspend_enter() (and analogously for > > power_switch_state(POWER_SSTATE, 0, 0, cpu)). > The ACPI code is not using the SSTATE event. > Indeed inserting a tracepoint at > kernel/power/suspend.c:suspend_enter() is more generic. I will correct > this. OK > > Moreover, why is the cpu argument necessary for POWER_SSTATE at all? > The cpu_id parameter is present in all events prototypes. This is not > needed. I will correct this. OK Thanks, Rafael