diff options
author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-05-04 23:53:35 +0300 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-05-04 23:53:35 +0300 |
commit | bcf6ad8a4a3d002e8bc8f6639cdc119168f4e87b (patch) | |
tree | 6536efb9c4c8d199aca4118af959d79192bab716 /kernel/sched/idle.c | |
parent | a802ea96454570f3c526dd9d7ad8c706e570444d (diff) |
sched / idle: Eliminate the "reflect" check from cpuidle_idle_call()
Since cpuidle_reflect() should only be called if the idle state
to enter was selected by cpuidle_select(), there is the "reflect"
variable in cpuidle_idle_call() whose value is used to determine
whether or not that is the case.
However, if the entire code run between the conditional setting
"reflect" and the call to cpuidle_reflect() is moved to a separate
function, it will be possible to call that new function in both
branches of the conditional, in which case cpuidle_reflect() will
only need to be called from one of them too and the "reflect"
variable won't be necessary any more.
This eliminates one check made by cpuidle_idle_call() on the majority
of its invocations, so change the code as described.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Diffstat (limited to 'kernel/sched/idle.c')
-rw-r--r-- | kernel/sched/idle.c | 90 |
1 files changed, 46 insertions, 44 deletions
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index ae7c0be90d16..9c919b42f846 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -79,6 +79,46 @@ static void default_idle_call(void) arch_cpu_idle(); } +static int call_cpuidle(struct cpuidle_driver *drv, struct cpuidle_device *dev, + int next_state) +{ + int entered_state; + + /* Fall back to the default arch idle method on errors. */ + if (next_state < 0) { + default_idle_call(); + return next_state; + } + + /* + * The idle task must be scheduled, it is pointless to go to idle, just + * update no idle residency and return. + */ + if (current_clr_polling_and_test()) { + dev->last_residency = 0; + local_irq_enable(); + return -EBUSY; + } + + /* Take note of the planned idle state. */ + idle_set_state(this_rq(), &drv->states[next_state]); + + /* + * Enter the idle state previously returned by the governor decision. + * This function will block until an interrupt occurs and will take + * care of re-enabling the local interrupts + */ + entered_state = cpuidle_enter(drv, dev, next_state); + + /* The cpu is no longer idle or about to enter idle. */ + idle_set_state(this_rq(), NULL); + + if (entered_state == -EBUSY) + default_idle_call(); + + return entered_state; +} + /** * cpuidle_idle_call - the main idle function * @@ -93,7 +133,6 @@ static void cpuidle_idle_call(void) struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); int next_state, entered_state; - bool reflect; /* * Check if the idle task must be rescheduled. If it is the @@ -138,56 +177,19 @@ static void cpuidle_idle_call(void) goto exit_idle; } - reflect = false; next_state = cpuidle_find_deepest_state(drv, dev); + call_cpuidle(drv, dev, next_state); } else { - reflect = true; /* * Ask the cpuidle framework to choose a convenient idle state. */ next_state = cpuidle_select(drv, dev); - } - /* Fall back to the default arch idle method on errors. */ - if (next_state < 0) { - default_idle_call(); - goto exit_idle; - } - - /* - * The idle task must be scheduled, it is pointless to - * go to idle, just update no idle residency and get - * out of this function - */ - if (current_clr_polling_and_test()) { - dev->last_residency = 0; - entered_state = next_state; - local_irq_enable(); - goto exit_idle; - } - - /* Take note of the planned idle state. */ - idle_set_state(this_rq(), &drv->states[next_state]); - - /* - * Enter the idle state previously returned by the governor decision. - * This function will block until an interrupt occurs and will take - * care of re-enabling the local interrupts - */ - entered_state = cpuidle_enter(drv, dev, next_state); - - /* The cpu is no longer idle or about to enter idle. */ - idle_set_state(this_rq(), NULL); - - if (entered_state == -EBUSY) { - default_idle_call(); - goto exit_idle; - } - - /* - * Give the governor an opportunity to reflect on the outcome - */ - if (reflect) + entered_state = call_cpuidle(drv, dev, next_state); + /* + * Give the governor an opportunity to reflect on the outcome + */ cpuidle_reflect(dev, entered_state); + } exit_idle: __current_set_polling(); |