Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH v4 0/2] cpufreq: cpufreq_driver_lock is hot on large systems | Date | Tue, 12 Mar 2013 00:23:08 +0100 |
| |
On Friday, February 22, 2013 10:24:33 AM Nathan Zimmer wrote: > 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 significant 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. > > v2: Rebase > > v3: Read the RCU documentation instead of skimming it. Also I based on > git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git pm+acpi-3.9-rc1 > I assumed that was what you would prefer Rafael. > > v4: Removed an unnecessary syncronize_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 | 286 ++++++++++++++++++++++++++++++++++------------ > 1 file changed, 211 insertions(+), 75 deletions(-)
I'm going to take patch [1/2] for v3.10, but patch [2/2] still needs some work it seems. Is that correct? If so, are you going to send an update?
Rafael
-- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.
| |