From: Nathan Zimmer <nzimmer@sgi.com>
To: rjw@sisk.pl
Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
cpufreq@vger.kernel.org, Nathan Zimmer <nzimmer@sgi.com>
Subject: [PATCH 0/2] cpufreq: cpufreq_driver_lock is hot on large systems
Date: Mon, 4 Feb 2013 16:45:11 -0600 [thread overview]
Message-ID: <1360017913-25667-1-git-send-email-nzimmer@sgi.com> (raw)
I am noticing the cpufreq_driver_lock is quite hot.
On an idle 512 system perf shows me most of the system time is spent on this
lock. This is quite signifigant as top shows 5% of time in system time.
My solution was to first convert the lock to a rwlock and then to the rcu.
Nathan Zimmer (2):
cpufreq: Convert the cpufreq_driver_lock to a rwlock
cpufreq: Convert the cpufreq_driver_lock to use the rcu
drivers/cpufreq/cpufreq.c | 139 ++++++++++++++++++++++++++--------------------
1 file changed, 79 insertions(+), 60 deletions(-)
--
1.8.0.1
next reply other threads:[~2013-02-04 22:45 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-04 22:45 Nathan Zimmer [this message]
2013-02-04 22:45 ` [PATCH 1/2] cpufreq: Convert the cpufreq_driver_lock to a rwlock Nathan Zimmer
2013-02-05 8:11 ` Viresh Kumar
2013-02-04 22:45 ` [PATCH 2/2] cpufreq: Convert the cpufreq_driver_lock to use the rcu Nathan Zimmer
2013-02-05 1:07 ` [PATCH 0/2] cpufreq: cpufreq_driver_lock is hot on large systems Rafael J. Wysocki
2013-02-05 8:28 ` Viresh Kumar
2013-02-05 10:03 ` Rafael J. Wysocki
2013-02-05 9:58 ` Viresh Kumar
2013-02-05 10:13 ` Rafael J. Wysocki
2013-02-05 14:58 ` Nathan Zimmer
2013-02-05 22:00 ` Rafael J. Wysocki
2013-02-06 2:04 ` [PATCH v2 linux-next " Nathan Zimmer
2013-02-06 2:04 ` [PATCH v2 linux-next 1/2] cpufreq: Convert the cpufreq_driver_lock to a rwlock Nathan Zimmer
2013-02-06 2:47 ` Viresh Kumar
2013-02-06 2:04 ` [PATCH v2 linux-next 2/2] cpufreq: Convert the cpufreq_driver_lock to use the rcu Nathan Zimmer
2013-02-06 2:52 ` Viresh Kumar
2013-02-06 8:51 ` Viresh Kumar
2013-02-06 13:00 ` Rafael J. Wysocki
2013-02-07 23:29 ` Rafael J. Wysocki
2013-02-11 17:13 ` Nathan Zimmer
2013-02-11 19:36 ` Rafael J. Wysocki
2013-02-12 4:03 ` Nathan Zimmer
2013-02-12 15:59 ` Paul E. McKenney
2013-02-13 13:20 ` Rafael J. Wysocki
2013-02-20 23:56 ` [PATCH v3 0/2] cpufreq: cpufreq_driver_lock is hot on large systems Nathan Zimmer
2013-02-20 23:56 ` [PATCH v3 1/2] cpufreq: Convert the cpufreq_driver_lock to a rwlock Nathan Zimmer
2013-02-20 23:56 ` [PATCH v3 2/2] cpufreq: Convert the cpufreq_driver_lock to use the rcu Nathan Zimmer
2013-02-21 5:50 ` Viresh Kumar
2013-02-21 17:49 ` Nathan Zimmer
2013-02-22 16:24 ` [PATCH v4 0/2] cpufreq: cpufreq_driver_lock is hot on large systems Nathan Zimmer
2013-02-22 16:24 ` [PATCH v4 1/2] cpufreq: Convert the cpufreq_driver_lock to a rwlock Nathan Zimmer
2013-02-23 3:57 ` Viresh Kumar
2013-02-22 16:24 ` [PATCH v4 2/2] cpufreq: Convert the cpufreq_driver_lock to use the rcu Nathan Zimmer
2013-02-23 3:39 ` Viresh Kumar
2013-02-25 20:07 ` Nathan Zimmer
2013-03-11 23:23 ` [PATCH v4 0/2] cpufreq: cpufreq_driver_lock is hot on large systems Rafael J. Wysocki
2013-03-13 20:50 ` Nathan Zimmer
2013-04-01 15:33 ` [PATCH v5] cpufreq: split the cpufreq_driver_lock and use the rcu (was cpufreq: cpufreq_driver_lock is hot on large systems) Nathan Zimmer
2013-04-01 16:28 ` Viresh Kumar
2013-04-01 17:17 ` Nathan Zimmer
2013-04-01 20:11 ` [PATCH v6 0/2] cpufreq: cpufreq_driver_lock is hot on large systems Nathan Zimmer
2013-04-01 20:11 ` [PATCH v6 1/2] cpufreq: split the cpufreq_driver_lock and use the rcu Nathan Zimmer
2013-04-02 5:05 ` Viresh Kumar
2013-04-02 14:55 ` Nathan Zimmer
2013-04-02 14:59 ` Viresh Kumar
2013-04-02 15:40 ` Nathan Zimmer
2013-04-02 15:52 ` Viresh Kumar
2013-04-02 22:57 ` Rafael J. Wysocki
2013-04-03 5:25 ` Viresh Kumar
2013-04-01 20:11 ` [PATCH v6 2/2] cpufreq: covert the cpufreq_data_lock to a spinlock Nathan Zimmer
2013-04-01 20:41 ` Rafael J. Wysocki
2013-04-02 0:56 ` Nathan Zimmer
2013-04-02 5:04 ` Viresh Kumar
2013-04-02 12:48 ` Rafael J. Wysocki
2013-04-02 14:58 ` Nathan Zimmer
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