From mboxrd@z Thu Jan 1 00:00:00 1970 From: jonghwa3.lee@samsung.com Subject: Re: [PATCH 3/3] Thermal:core: Handle trips focused on current trip point only. Date: Tue, 21 May 2013 12:40:45 +0900 Message-ID: <519AECBD.9060202@samsung.com> References: <1368870663-1225-1-git-send-email-jonghwa3.lee@samsung.com> <744357E9AAD1214791ACBA4B0B90926301102442@SHSMSX101.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mailout4.samsung.com ([203.254.224.34]:30115 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753583Ab3EUDk4 (ORCPT ); Mon, 20 May 2013 23:40:56 -0400 In-reply-to: <744357E9AAD1214791ACBA4B0B90926301102442@SHSMSX101.ccr.corp.intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: "Zhang, Rui" Cc: "linux-pm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Eduardo Valentin , Amit Dinel Kachhap , MyungJoo Ham On 2013=EB=85=84 05=EC=9B=94 21=EC=9D=BC 01:00, Zhang, Rui wrote: >=20 >=20 >> -----Original Message----- >> From: Jonghwa Lee [mailto:jonghwa3.lee@samsung.com] >> Sent: Saturday, May 18, 2013 5:51 PM >> To: linux-pm@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org; Zhang, Rui; Eduardo Valentin; Amit >> Dinel Kachhap; Jonghwa Lee; MyungJoo Ham >> Subject: [PATCH 3/3] Thermal:core: Handle trips focused on current t= rip >> point only. >> Importance: High >> >> When thermal zone device is updated, it doesn't need to check every >> trip points and its handling mathod even current temperature doesn't >> exceed the trip's temperature. To modify those dissipatve mechanism, >> this patch introduces the way to get current thermal trip point to c= all >> only correspond trip point handling. >> >> Signed-off-by: Jonghwa Lee >> Signed-off-by: MyungJoo Ham >=20 > NAK. >=20 >> --- >> drivers/thermal/thermal_core.c | 28 +++++++++++++++++----------- >> 1 file changed, 17 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/thermal/thermal_core.c >> b/drivers/thermal/thermal_core.c index ce4384a..1cc4825 100644 >> --- a/drivers/thermal/thermal_core.c >> +++ b/drivers/thermal/thermal_core.c >> @@ -333,14 +333,6 @@ static void handle_non_critical_trips(struct >> thermal_zone_device *tz, static void handle_critical_trips(struct >> thermal_zone_device *tz, >> int trip, enum thermal_trip_type trip_type) { >> - long trip_temp; >> - >> - tz->ops->get_trip_temp(tz, trip, &trip_temp); >> - >> - /* If we have not crossed the trip_temp, we do not care. */ >> - if (tz->temperature < trip_temp) >> - return; >> - >> if (tz->ops->notify) >> tz->ops->notify(tz, trip, trip_type); >> >> @@ -437,14 +429,28 @@ static void update_temperature(struct >> thermal_zone_device *tz) >> mutex_unlock(&tz->lock); >> } >> >> +static int thermal_zone_get_current_trip(struct thermal_zone_device >> +*tz) { >> + int trip; >> + long trip_temp; >> + >> + for (trip =3D tz->trips - 1; trip > 0; trip--) { >> + tz->ops->get_trip_temp(tz, trip, &trip_temp); >> + if (tz->temperature > trip_temp) >> + continue; >> + } >> + return trip; >> +} >> + >> void thermal_zone_device_update(struct thermal_zone_device *tz) { >> - int count; >> + int trip; >> >> update_temperature(tz); >> >> - for (count =3D 0; count < tz->trips; count++) >> - handle_thermal_trip(tz, count); >> + trip =3D thermal_zone_get_current_trip(tz); >> + >> + handle_thermal_trip(tz, trip); >=20 > Say, trip point 1 for thermal zone 0 is 60C, > The system is running above 60C for somethime, > thus the thermal_instance for this trip point is running at upper_lim= it. > When the temperature suddenly drops below 60C, > we still need to handle trip point 1 to deactivate it. >=20 Okay, I understood. I missed the point that governor will handle a cool= ing device within certain trip point described in thermal instance. But still I don't think this is the best behaviour. Let say we were in = trip level 2nd and moving to trip level 1st then we should call governor twi= ce for applying trip 1 level. Why don't we just call once? And whenever we cal= l handle_thermal_trip() with all trips, monitor_thermal_work() will also = be called at the same time. I think we can make this work more clearly and intuit= ively. let me think of it more,,, Thanks, Jonghwa. > Thanks, > rui >> } >> EXPORT_SYMBOL_GPL(thermal_zone_device_update); >> >> -- >> 1.7.9.5 >=20 >=20