[patch 09/39] hrtimer: Use a bits for various boolean indicators

From: Thomas Gleixner
Date: Tue Apr 14 2015 - 17:17:12 EST


No point in wasting 12 byte storage space. Generates better code as well.

Text size reduction:
x8664 -64, i386 -16, ARM -132, ARM64 -0, power64 -48

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
include/linux/hrtimer.h | 6 +++---
kernel/time/hrtimer.c | 24 ++++++++++++++++--------
2 files changed, 19 insertions(+), 11 deletions(-)

Index: tip/include/linux/hrtimer.h
===================================================================
--- tip.orig/include/linux/hrtimer.h
+++ tip/include/linux/hrtimer.h
@@ -181,10 +181,10 @@ struct hrtimer_cpu_base {
unsigned int active_bases;
unsigned int clock_was_set_seq;
#ifdef CONFIG_HIGH_RES_TIMERS
+ unsigned int in_hrtirq : 1,
+ hres_active : 1,
+ hang_detected : 1;
ktime_t expires_next;
- int in_hrtirq;
- int hres_active;
- int hang_detected;
unsigned int nr_events;
unsigned int nr_retries;
unsigned int nr_hangs;
Index: tip/kernel/time/hrtimer.c
===================================================================
--- tip.orig/kernel/time/hrtimer.c
+++ tip/kernel/time/hrtimer.c
@@ -492,9 +492,14 @@ static inline int hrtimer_is_hres_enable
/*
* Is the high resolution mode active ?
*/
+static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *cpu_base)
+{
+ return cpu_base->hres_active;
+}
+
static inline int hrtimer_hres_active(void)
{
- return __this_cpu_read(hrtimer_bases.hres_active);
+ return __hrtimer_hres_active(this_cpu_ptr(&hrtimer_bases));
}

/*
@@ -628,7 +633,7 @@ static void retrigger_next_event(void *a
{
struct hrtimer_cpu_base *base = this_cpu_ptr(&hrtimer_bases);

- if (!hrtimer_hres_active())
+ if (!base->hres_active)
return;

raw_spin_lock(&base->lock);
@@ -685,6 +690,7 @@ void clock_was_set_delayed(void)

#else

+static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *b) { return 0; }
static inline int hrtimer_hres_active(void) { return 0; }
static inline int hrtimer_is_hres_enabled(void) { return 0; }
static inline int hrtimer_switch_to_hres(void) { return 0; }
@@ -854,25 +860,27 @@ static void __remove_hrtimer(struct hrti
struct hrtimer_clock_base *base,
unsigned long newstate, int reprogram)
{
+ struct hrtimer_cpu_base *cpu_base = base->cpu_base;
struct timerqueue_node *next_timer;
+
if (!(timer->state & HRTIMER_STATE_ENQUEUED))
goto out;

next_timer = timerqueue_getnext(&base->active);
timerqueue_del(&base->active, &timer->node);
if (!timerqueue_getnext(&base->active))
- base->cpu_base->active_bases &= ~(1 << base->index);
+ cpu_base->active_bases &= ~(1 << base->index);

if (&timer->node == next_timer) {
#ifdef CONFIG_HIGH_RES_TIMERS
/* Reprogram the clock event device. if enabled */
- if (reprogram && hrtimer_hres_active()) {
+ if (reprogram && cpu_base->hres_active) {
ktime_t expires;

expires = ktime_sub(hrtimer_get_expires(timer),
base->offset);
- if (base->cpu_base->expires_next.tv64 == expires.tv64)
- hrtimer_force_reprogram(base->cpu_base, 1);
+ if (cpu_base->expires_next.tv64 == expires.tv64)
+ hrtimer_force_reprogram(cpu_base, 1);
}
#endif
}
@@ -1106,7 +1114,7 @@ ktime_t hrtimer_get_next_event(void)

raw_spin_lock_irqsave(&cpu_base->lock, flags);

- if (!hrtimer_hres_active())
+ if (!__hrtimer_hres_active(cpu_base))
mindelta = ktime_sub(__hrtimer_get_next_event(cpu_base),
ktime_get());

@@ -1404,7 +1412,7 @@ void hrtimer_run_queues(void)
struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
ktime_t now;

- if (hrtimer_hres_active())
+ if (__hrtimer_hres_active(cpu_base))
return;

raw_spin_lock(&cpu_base->lock);


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