Re: [PATCH] cpufreq: stats: Make the stats code non-modular
From: Viresh Kumar
Date: Thu May 26 2016 - 00:59:57 EST
On 26-05-16, 00:23, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> The modularity of cpufreq_stats is quite problematic.
> First off, the usage of policy notifiers for the initialization
> and cleanup in the cpufreq_stats module is inherently racy with
> respect to CPU offline/online and the initialization and cleanup
> of the cpufreq driver.
> Second, fast frequency switching (used by the schedutil governor)
> cannot be enabled if any transition notifiers are registered, so
> if the cpufreq_stats module (that registers a transition notifier
> for updating transition statistics) is loaded, the schedutil governor
> cannot use fast frequency switching.
> On the other hand, allowing cpufreq_stats to be built as a module
> doesn't really add much value. Arguably, there's not much reason
> for that code to be modular at all.
> For the above reasons, make the cpufreq stats code non-modular,
> modify the core to invoke functions provided by that code directly
> and drop the notifiers from it.
> While at it, clean up Kconfig help for the CPU_FREQ_STAT and
> CPU_FREQ_STAT_DETAILS options.
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> drivers/cpufreq/Kconfig | 13 +--
> drivers/cpufreq/cpufreq.c | 4 +
> drivers/cpufreq/cpufreq_stats.c | 146 +++-------------------------------------
> include/linux/cpufreq.h | 12 +++
> 4 files changed, 34 insertions(+), 141 deletions(-)
Looks far better now :)
Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>