diff options
| author | Konstantin Khlebnikov <khlebnikov@openvz.org> | 2012-12-15 00:22:02 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-01-03 13:11:18 +0100 |
| commit | 56836fb4dab8fe906b934b231b04c33c180f8da5 (patch) | |
| tree | 4ad98361223482eeb8b0f3a4485b7bb4ba4c012d /drivers/cpufreq/cpufreq_stats.c | |
| parent | Linux 3.8-rc2 (diff) | |
| download | linux-56836fb4dab8fe906b934b231b04c33c180f8da5.tar.xz linux-56836fb4dab8fe906b934b231b04c33c180f8da5.zip | |
cpufreq / stats: fix race between stats allocation and first usage
This patch forces complete struct cpufreq_stats allocation for all cpus before
registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
in this case cpufreq_stats_table already exists, but stat->freq_table is NULL.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq/cpufreq_stats.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_stats.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index e40e50809644..9d7732b81044 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void) if (ret) return ret; + register_hotcpu_notifier(&cpufreq_stat_cpu_notifier); + for_each_online_cpu(cpu) + cpufreq_update_policy(cpu); + ret = cpufreq_register_notifier(¬ifier_trans_block, CPUFREQ_TRANSITION_NOTIFIER); if (ret) { cpufreq_unregister_notifier(¬ifier_policy_block, CPUFREQ_POLICY_NOTIFIER); + unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier); + for_each_online_cpu(cpu) + cpufreq_stats_free_table(cpu); return ret; } - register_hotcpu_notifier(&cpufreq_stat_cpu_notifier); - for_each_online_cpu(cpu) { - cpufreq_update_policy(cpu); - } return 0; } static void __exit cpufreq_stats_exit(void) |