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hrtimer: Unconfuse switch_hrtimer_base() a bit 

The variable called "this_base" is confusing because its name suggests
it's of "struct hrtimer_clock_base" type, along with "base" and "new_base"
which doesn't help understanding this complicated function.

Make its name clearer and fix the misleading comment while at it.

[ tglx: Fixed the comment for real ]

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1439907509-9553-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Frederic Weisbecker 2015-08-18 16:18:29 +02:00 committed by Thomas Gleixner
parent 662b3e1946
commit b48362d8aa
1 changed files with 17 additions and 8 deletions
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25
kernel/time/hrtimer.c
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@ -196,18 +196,27 @@ struct hrtimer_cpu_base *get_target_base(struct hrtimer_cpu_base *base,
#endif
/*
* Switch the timer base to the current CPU when possible.
* We switch the timer base to a power-optimized selected CPU target,
* if:
* - NO_HZ_COMMON is enabled
* - timer migration is enabled
* - the timer callback is not running
* - the timer is not the first expiring timer on the new target
*
* If one of the above requirements is not fulfilled we move the timer
* to the current CPU or leave it on the previously assigned CPU if
* the timer callback is currently running.
*/
static inline struct hrtimer_clock_base *
switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,
int pinned)
{
struct hrtimer_cpu_base *new_cpu_base, *this_base;
struct hrtimer_cpu_base *new_cpu_base, *this_cpu_base;
struct hrtimer_clock_base *new_base;
int basenum = base->index;
this_base = this_cpu_ptr(&hrtimer_bases);
new_cpu_base = get_target_base(this_base, pinned);
this_cpu_base = this_cpu_ptr(&hrtimer_bases);
new_cpu_base = get_target_base(this_cpu_base, pinned);
again:
new_base = &new_cpu_base->clock_base[basenum];
@ -229,19 +238,19 @@ switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,
raw_spin_unlock(&base->cpu_base->lock);
raw_spin_lock(&new_base->cpu_base->lock);
if (new_cpu_base != this_base &&
if (new_cpu_base != this_cpu_base &&
hrtimer_check_target(timer, new_base)) {
raw_spin_unlock(&new_base->cpu_base->lock);
raw_spin_lock(&base->cpu_base->lock);
new_cpu_base = this_base;
new_cpu_base = this_cpu_base;
timer->base = base;
goto again;
}
timer->base = new_base;
} else {
if (new_cpu_base != this_base &&
if (new_cpu_base != this_cpu_base &&
hrtimer_check_target(timer, new_base)) {
new_cpu_base = this_base;
new_cpu_base = this_cpu_base;
goto again;
}
}