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    SubjectRe: [PATCH v2 12/12] cpufreq: governor: Narrow down the dbs_data_mutex coverage
    On 18-02-16, 18:58, Rafael J. Wysocki wrote:
    > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    > Subject: [PATCH] cpufreq: governor: Narrow down the dbs_data_mutex coverage
    >
    > Since cpufreq_governor_dbs() is now always called with policy->rwsem
    > held, it cannot be executed twice in parallel for the same policy.
    > Thus it is not necessary to hold dbs_data_mutex around the invocations
    > of cpufreq_governor_start/stop/limits() from it as those functions
    > never modify any data that can be shared between different policies.
    >
    > However, cpufreq_governor_dbs() may be executed twice in parallal
    > for different policies using the same gov->gdbs_data object and
    > dbs_data_mutex is still necessary to protect that object against
    > concurrent updates.
    >
    > For this reason, narrow down the dbs_data_mutex locking to
    > cpufreq_governor_init/exit() where it is needed and rename the
    > mutex to gov_dbs_data_mutex to reflect its purpose.
    >
    > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    > ---
    > drivers/cpufreq/cpufreq_governor.c | 46 ++++++++++++++++++-------------------
    > 1 file changed, 23 insertions(+), 23 deletions(-)

    Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

    --
    viresh

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