From: Peter Zijlstra <peterz@infradead.org>
To: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Steve Muckle <steve.muckle@linaro.org>,
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
Juri Lelli <juri.lelli@arm.com>,
"Rafael J. Wysocki" <rafael@kernel.org>,
Linux PM list <linux-pm@vger.kernel.org>,
Ingo Molnar <mingo@kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Viresh Kumar <viresh.kumar@linaro.org>,
Thomas Gleixner <tglx@linutronix.de>,
"Rafael J. Wysocki" <rjw@rjwysocki.net>
Subject: Re: [PATCH v10 1/3] cpufreq: Add mechanism for registering utilization update callbacks
Date: Mon, 22 Feb 2016 16:31:32 +0100 [thread overview]
Message-ID: <20160222153132.GI6357@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <CAKfTPtBEREXmhOdZSsY0DM76YdZg=WJn7TN1ADTfAQ806+YN5w@mail.gmail.com>
On Mon, Feb 22, 2016 at 03:33:02PM +0100, Vincent Guittot wrote:
> > Right, so I had a wee look at that again, and had a quick chat with Juri
> > on IRC. So the main difference seems to be that you guys want to know
> > why the utilization changed, as opposed to purely _that_ it changed.
>
> Yes, the main goal was to be able to filter the useful and useless
> update of rq's utilization in order to minimize/optimize the trig of
> an update of the frequency. These patches have been made for a cpufreq
> driver that reacts far slower than scheduler. It's might worth
> starting with a simple solution and update it after
Right, always start simple :-)
> > And hence you have callbacks all over the place.
> >
> > I'm not too sure I really like that too much, it bloats the code and
> > somewhat obfuscates the point.
> >
> > So I would really like there to be just the one callback when we
> > actually compute a new number, and that is update_load_avg().
> >
> > Now I think we can 'easily' propagate the information you want into
> > update_load_avg() (see below), but I would like to see actual arguments
> > for why you would need this.
>
> Your proposal is interesting except that we are interested in the rq's
> utilization more that se's ones so we should better use
> update_cfs_rq_load_avg and few additional place like
> attach_entity_load_avg which bypasses update_cfs_rq_load_avg to update
> rq's utilization and load
Ah, so the intent was to use the rq->cfs util, but I might have gotten
a little lost in the load update code (I always get confused by that
code if I haven't looked at it for a while).
We can put the hook in update_cfs_rq_load_avg(), that shouldn't be a
problem.
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2859,29 +2859,6 @@ static inline int update_cfs_rq_load_avg
cfs_rq->load_last_update_time_copy = sa->last_update_time;
#endif
- return decayed || removed;
-}
-
-/* Update task and its cfs_rq load average */
-static inline void update_load_avg(struct sched_entity *se, int update_tg,
- enum load_update_type type)
-{
- struct cfs_rq *cfs_rq = cfs_rq_of(se);
- u64 now = cfs_rq_clock_task(cfs_rq);
- struct rq *rq = rq_of(cfs_rq);
- int cpu = cpu_of(rq);
-
- /*
- * Track task load average for carrying it to new CPU after migrated, and
- * track group sched_entity load average for task_h_load calc in migration
- */
- __update_load_avg(now, cpu, &se->avg,
- se->on_rq * scale_load_down(se->load.weight),
- cfs_rq->curr == se, NULL);
-
- if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg)
- update_tg_load_avg(cfs_rq, 0);
-
if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) {
unsigned long max = rq->cpu_capacity_orig;
@@ -2904,6 +2881,29 @@ static inline void update_load_avg(struc
cpufreq_update_util(rq_clock(rq),
min(cfs_rq->avg.util_avg, max), max);
}
+
+ return decayed || removed;
+}
+
+/* Update task and its cfs_rq load average */
+static inline void update_load_avg(struct sched_entity *se, int update_tg,
+ enum load_update_type type)
+{
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ u64 now = cfs_rq_clock_task(cfs_rq);
+ struct rq *rq = rq_of(cfs_rq);
+ int cpu = cpu_of(rq);
+
+ /*
+ * Track task load average for carrying it to new CPU after migrated, and
+ * track group sched_entity load average for task_h_load calc in migration
+ */
+ __update_load_avg(now, cpu, &se->avg,
+ se->on_rq * scale_load_down(se->load.weight),
+ cfs_rq->curr == se, NULL);
+
+ if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg)
+ update_tg_load_avg(cfs_rq, 0);
}
static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
next prev parent reply other threads:[~2016-02-22 15:31 UTC|newest]
Thread overview: 134+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-29 22:52 [PATCH 0/3] cpufreq: Replace timers with utilization update callbacks Rafael J. Wysocki
2016-01-29 22:53 ` [PATCH 1/3] cpufreq: Add a mechanism for registering " Rafael J. Wysocki
2016-02-04 3:31 ` Viresh Kumar
2016-01-29 22:56 ` [PATCH 2/3] cpufreq: intel_pstate: Replace timers with " Rafael J. Wysocki
2016-01-29 22:59 ` [PATCH 3/3] cpufreq: governor: " Rafael J. Wysocki
2016-02-03 1:16 ` [Update][PATCH " Rafael J. Wysocki
2016-02-04 4:49 ` Viresh Kumar
2016-02-04 10:54 ` Rafael J. Wysocki
2016-02-05 1:28 ` [PATCH 3/3 v3] " Rafael J. Wysocki
2016-02-05 6:50 ` Viresh Kumar
2016-02-05 13:36 ` Rafael J. Wysocki
2016-02-05 14:47 ` Viresh Kumar
2016-02-05 23:10 ` Rafael J. Wysocki
2016-02-07 9:10 ` Viresh Kumar
2016-02-07 14:43 ` Rafael J. Wysocki
2016-02-08 2:08 ` Rafael J. Wysocki
2016-02-08 11:52 ` Viresh Kumar
2016-02-08 12:52 ` Rafael J. Wysocki
2016-02-08 13:40 ` Rafael J. Wysocki
2016-02-05 23:01 ` Rafael J. Wysocki
2016-02-06 3:40 ` [PATCH 3/3 v4] " Rafael J. Wysocki
2016-02-07 9:20 ` Viresh Kumar
2016-02-07 14:36 ` Rafael J. Wysocki
2016-02-07 14:50 ` [PATCH 3/3 v5] " Rafael J. Wysocki
2016-02-07 15:36 ` Viresh Kumar
2016-02-09 10:01 ` Gautham R Shenoy
2016-02-09 18:49 ` Rafael J. Wysocki
2016-02-03 22:20 ` [PATCH 0/3] cpufreq: " Rafael J. Wysocki
2016-02-04 0:08 ` Srinivas Pandruvada
2016-02-04 17:16 ` Rafael J. Wysocki
2016-02-04 10:51 ` Juri Lelli
2016-02-04 17:19 ` Rafael J. Wysocki
2016-02-08 23:06 ` Rafael J. Wysocki
2016-02-09 0:39 ` Steve Muckle
2016-02-09 1:01 ` Rafael J. Wysocki
2016-02-09 20:05 ` Rafael J. Wysocki
2016-02-10 1:02 ` Steve Muckle
2016-02-10 1:57 ` Rafael J. Wysocki
2016-02-10 3:09 ` Rafael J. Wysocki
2016-02-10 19:47 ` Steve Muckle
2016-02-10 21:49 ` Rafael J. Wysocki
2016-02-10 22:07 ` Steve Muckle
2016-02-10 22:12 ` Rafael J. Wysocki
2016-02-11 11:59 ` Peter Zijlstra
2016-02-11 12:24 ` Juri Lelli
2016-02-11 15:26 ` Peter Zijlstra
2016-02-11 18:23 ` Vincent Guittot
2016-02-12 14:04 ` Peter Zijlstra
2016-02-12 14:48 ` Vincent Guittot
2016-03-01 13:58 ` Peter Zijlstra
2016-03-01 14:17 ` Juri Lelli
2016-03-01 14:24 ` Peter Zijlstra
2016-03-01 14:26 ` Peter Zijlstra
2016-03-01 14:42 ` Juri Lelli
2016-03-01 15:04 ` Peter Zijlstra
2016-03-01 19:49 ` Rafael J. Wysocki
2016-03-01 14:58 ` Vincent Guittot
2016-02-11 17:06 ` Steve Muckle
2016-02-11 17:30 ` Peter Zijlstra
2016-02-11 17:34 ` Rafael J. Wysocki
2016-02-11 17:38 ` Peter Zijlstra
2016-02-11 18:52 ` Steve Muckle
2016-02-11 19:04 ` Rafael J. Wysocki
2016-02-12 13:43 ` Rafael J. Wysocki
2016-02-12 14:10 ` Peter Zijlstra
2016-02-12 16:01 ` Rafael J. Wysocki
2016-02-12 16:15 ` Rafael J. Wysocki
2016-02-12 16:53 ` Ashwin Chaugule
2016-02-12 23:14 ` Rafael J. Wysocki
2016-02-12 17:02 ` Doug Smythies
2016-02-12 23:17 ` Rafael J. Wysocki
2016-02-10 12:33 ` Juri Lelli
2016-02-10 13:23 ` Rafael J. Wysocki
2016-02-10 14:03 ` Juri Lelli
2016-02-10 14:26 ` Rafael J. Wysocki
2016-02-10 14:46 ` Juri Lelli
2016-02-10 15:46 ` Rafael J. Wysocki
2016-02-10 16:05 ` Juri Lelli
2016-02-11 11:51 ` Peter Zijlstra
2016-02-11 12:08 ` Rafael J. Wysocki
2016-02-11 15:29 ` Peter Zijlstra
2016-02-11 15:58 ` Rafael J. Wysocki
2016-02-11 20:47 ` Rafael J. Wysocki
2016-02-10 15:17 ` [PATCH v6 " Rafael J. Wysocki
2016-02-10 15:21 ` [PATCH v6 1/3] cpufreq: Add mechanism for registering " Rafael J. Wysocki
2016-02-10 23:01 ` [PATCH v7 " Rafael J. Wysocki
2016-02-11 17:30 ` [PATCH v8 " Rafael J. Wysocki
2016-02-12 13:16 ` [PATCH v9 " Rafael J. Wysocki
2016-02-15 21:47 ` [PATCH v10 " Rafael J. Wysocki
2016-02-18 20:22 ` Rafael J. Wysocki
2016-02-19 8:09 ` Juri Lelli
2016-02-19 16:42 ` Srinivas Pandruvada
2016-02-19 17:26 ` Juri Lelli
2016-02-19 22:26 ` Rafael J. Wysocki
2016-02-22 9:42 ` Juri Lelli
2016-02-22 21:41 ` Rafael J. Wysocki
2016-02-23 11:10 ` Juri Lelli
2016-02-24 1:52 ` Rafael J. Wysocki
2016-02-22 10:45 ` Viresh Kumar
2016-02-19 17:28 ` Steve Muckle
2016-02-19 22:35 ` Rafael J. Wysocki
2016-02-23 3:58 ` Steve Muckle
2016-02-22 10:52 ` Peter Zijlstra
2016-02-22 14:33 ` Vincent Guittot
2016-02-22 15:31 ` Peter Zijlstra [this message]
2016-02-22 14:40 ` Juri Lelli
2016-02-22 15:42 ` Peter Zijlstra
2016-02-22 21:46 ` Rafael J. Wysocki
2016-02-19 22:14 ` Rafael J. Wysocki
2016-02-22 9:32 ` Juri Lelli
2016-02-22 21:26 ` Rafael J. Wysocki
2016-02-23 11:01 ` Juri Lelli
2016-02-24 2:01 ` Rafael J. Wysocki
2016-03-08 19:24 ` Michael Turquette
2016-03-08 20:40 ` Rafael J. Wysocki
[not found] ` <20160308220632.4103.13377@quark.deferred.io>
2016-03-08 22:43 ` Rafael J. Wysocki
2016-03-09 12:35 ` Peter Zijlstra
2016-03-09 13:22 ` Rafael J. Wysocki
2016-03-09 13:32 ` Ingo Molnar
2016-03-09 13:39 ` Rafael J. Wysocki
2016-03-10 2:12 ` Vincent Guittot
2016-02-10 15:25 ` [PATCH v6 2/3] cpufreq: intel_pstate: Replace timers with " Rafael J. Wysocki
2016-02-10 15:36 ` [PATCH v6 3/3] cpufreq: governor: " Rafael J. Wysocki
2016-02-10 23:11 ` [PATCH v6 0/3] cpufreq: " Doug Smythies
2016-02-10 23:17 ` Rafael J. Wysocki
2016-02-11 22:50 ` Doug Smythies
2016-02-11 23:28 ` Rafael J. Wysocki
2016-02-12 1:02 ` Doug Smythies
2016-02-12 1:20 ` Rafael J. Wysocki
2016-02-12 7:25 ` Doug Smythies
2016-02-12 13:39 ` Rafael J. Wysocki
2016-02-12 17:33 ` Doug Smythies
2016-02-12 23:21 ` Rafael J. Wysocki
2016-02-11 6:02 ` Srinivas Pandruvada
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