From: Frederic Weisbecker <fweisbec@gmail.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
Frederic Weisbecker <fweisbec@gmail.com>
Subject: [PATCH 2/2] hrtimer: Unconfuse a bit switch_hrtimer_base
Date: Tue, 18 Aug 2015 16:18:29 +0200 [thread overview]
Message-ID: <1439907509-9553-3-git-send-email-fweisbec@gmail.com> (raw)
In-Reply-To: <1439907509-9553-1-git-send-email-fweisbec@gmail.com>
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 comments while at it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
---
kernel/time/hrtimer.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index f9eb21b..1828ed0 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -196,18 +196,20 @@ struct hrtimer_cpu_base *get_target_base(struct hrtimer_cpu_base *base,
#endif
/*
- * Switch the timer base to the current CPU when possible.
+ * Switch the timer base to a power-optimized selected CPU target.
+ * If that would involve clock reprogramming, which we can't do on a remote
+ * target, just switch to the current CPU.
*/
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 +231,19 @@ again:
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;
}
}
--
2.1.4
next prev parent reply other threads:[~2015-08-18 14:18 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-18 14:18 [PATCH 0/2] hrtimer: Boring cleanups Frederic Weisbecker
2015-08-18 14:18 ` [PATCH 1/2] hrtimer: Simplify get_target_base() returning current base Frederic Weisbecker
2015-08-18 16:39 ` [tip:timers/core] hrtimer: Simplify get_target_base() by " tip-bot for Frederic Weisbecker
2015-08-18 14:18 ` Frederic Weisbecker [this message]
2015-08-18 16:39 ` [tip:timers/core] hrtimer: Unconfuse switch_hrtimer_base() a bit tip-bot for Frederic Weisbecker
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