summaryrefslogtreecommitdiff
path: root/drivers/cpuidle
diff options
context:
space:
mode:
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2015-05-28 05:09:24 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2015-05-30 03:15:21 +0300
commit7d51d97925e6cbfa2f7f14e3e3aa363b35ee5c24 (patch)
treea95d7d6d2440aac67608c965b7386d0f160a04b6 /drivers/cpuidle
parent0d94039fabccaa81d87eafdac509d0dda4df2f7b (diff)
downloadlinux-7d51d97925e6cbfa2f7f14e3e3aa363b35ee5c24.tar.xz
cpuidle: Do not use CPUIDLE_DRIVER_STATE_START in cpuidle.c
The CPUIDLE_DRIVER_STATE_START symbol is defined as 1 only if CONFIG_ARCH_HAS_CPU_RELAX is set, otherwise it is defined as 0. However, if CONFIG_ARCH_HAS_CPU_RELAX is set, the first (index 0) entry in the cpuidle driver's table of states is overwritten with the default "poll" entry by the core. The "state" defined by the "poll" entry doesn't provide ->enter_dead and ->enter_freeze callbacks and its exit_latency is 0. For this reason, it is not necessary to use CPUIDLE_DRIVER_STATE_START in cpuidle_play_dead() (->enter_dead is NULL, so the "poll state" will be skipped by the loop). It also is arguably unuseful to return states with exit_latency equal to 0 from find_deepest_state(), so the function can be modified to start the loop from index 0 and the "poll state" will be skipped by it as a result of the check against latency_req. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Diffstat (limited to 'drivers/cpuidle')
-rw-r--r--drivers/cpuidle/cpuidle.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index af6dd599c464..7f1b8f507a56 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -65,7 +65,7 @@ int cpuidle_play_dead(void)
return -ENODEV;
/* Find lowest-power state that supports long-term idle */
- for (i = drv->state_count - 1; i >= CPUIDLE_DRIVER_STATE_START; i--)
+ for (i = drv->state_count - 1; i >= 0; i--)
if (drv->states[i].enter_dead)
return drv->states[i].enter_dead(dev, i);
@@ -79,9 +79,9 @@ static int find_deepest_state(struct cpuidle_driver *drv,
bool freeze)
{
unsigned int latency_req = 0;
- int i, ret = freeze ? -1 : CPUIDLE_DRIVER_STATE_START - 1;
+ int i, ret = -ENXIO;
- for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
+ for (i = 0; i < drv->state_count; i++) {
struct cpuidle_state *s = &drv->states[i];
struct cpuidle_state_usage *su = &dev->states_usage[i];