It is better to pass a struct cpufreq_stats pointer to cpufreq_stats_update() instead of a CPU number, because that's all it needs.
Even if we pass a cpu number to cpufreq_stats_update(), it reads the per-cpu variable to get 'stats' out of it. So we are doing these operations unnecessarily: - First getting the cpu number to pass to cpufreq_stats_update(), stat->cpu. - And then getting stats from the cpu, per_cpu(cpufreq_stats_table, cpu).
Reviewed-by: Prarit Bhargava prarit@redhat.com Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/cpufreq/cpufreq_stats.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index e9d68420b876..6c234f548601 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -33,13 +33,11 @@ struct cpufreq_stats {
static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table);
-static int cpufreq_stats_update(unsigned int cpu) +static int cpufreq_stats_update(struct cpufreq_stats *stat) { - struct cpufreq_stats *stat; unsigned long long cur_time = get_jiffies_64();
spin_lock(&cpufreq_stats_lock); - stat = per_cpu(cpufreq_stats_table, cpu); if (stat->time_in_state) stat->time_in_state[stat->last_index] += cur_time - stat->last_time; @@ -64,7 +62,7 @@ static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf) struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); if (!stat) return 0; - cpufreq_stats_update(stat->cpu); + cpufreq_stats_update(stat); for (i = 0; i < stat->state_num; i++) { len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i], (unsigned long long) @@ -82,7 +80,7 @@ static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf) struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); if (!stat) return 0; - cpufreq_stats_update(stat->cpu); + cpufreq_stats_update(stat); len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); len += snprintf(buf + len, PAGE_SIZE - len, " : "); for (i = 0; i < stat->state_num; i++) { @@ -307,7 +305,7 @@ static int cpufreq_stat_notifier_trans(struct notifier_block *nb, if (old_index == -1 || new_index == -1) return 0;
- cpufreq_stats_update(freq->cpu); + cpufreq_stats_update(stat);
if (old_index == new_index) return 0;