diff options
| author | Tero Kristo <tero.kristo@nokia.com> | 2011-02-24 17:19:23 +0200 |
|---|---|---|
| committer | Andi Kleen <ak@linux.intel.com> | 2011-08-01 13:54:53 -0700 |
| commit | 857053c1d4fcba46f8fdfcbc4926c1e70757d4a5 (patch) | |
| tree | 30019f92e567b79611546ad585b2a7ed048b4ecc /drivers | |
| parent | 500c1e95d2e4a846025091c8cabee761578fc6cc (diff) | |
cpuidle: menu: fixed wrapping timers at 4.294 seconds
commit 7467571f4480b273007517b26297c07154c73924 upstream.
Cpuidle menu governor is using u32 as a temporary datatype for storing
nanosecond values which wrap around at 4.294 seconds. This causes errors
in predicted sleep times resulting in higher than should be C state
selection and increased power consumption. This also breaks cpuidle
state residency statistics.
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 1b128702d300..fa0787bb8251 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -236,6 +236,7 @@ static int menu_select(struct cpuidle_device *dev) int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); int i; int multiplier; + struct timespec t; if (data->needs_update) { menu_update(dev); @@ -250,8 +251,9 @@ static int menu_select(struct cpuidle_device *dev) return 0; /* determine the expected residency time, round up */ + t = ktime_to_timespec(tick_nohz_get_sleep_length()); data->expected_us = - DIV_ROUND_UP((u32)ktime_to_ns(tick_nohz_get_sleep_length()), 1000); + t.tv_sec * USEC_PER_SEC + t.tv_nsec / NSEC_PER_USEC; data->bucket = which_bucket(data->expected_us); |