From: Viresh Kumar <viresh.kumar@linaro.org>
To: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>
Cc: linaro-kernel@lists.linaro.org, linux-kernel@vger.kernel.org,
Preeti U Murthy <preeti@linux.vnet.ibm.com>,
Viresh Kumar <viresh.kumar@linaro.org>
Subject: [PATCH V2 2/2] hrtimer: Iterate only over active clock-bases
Date: Tue, 7 Apr 2015 07:40:53 +0530 [thread overview]
Message-ID: <b884675ccbd86069d7e9ff6b0de35760c5d6a959.1428039899.git.viresh.kumar@linaro.org> (raw)
In-Reply-To: <cover.1428039899.git.viresh.kumar@linaro.org>
In-Reply-To: <cover.1428039899.git.viresh.kumar@linaro.org>
At several instances we iterate over all possible clock-bases for a
particular cpu-base. Whereas, we only need to iterate over active bases.
We already have per cpu-base 'active_bases' field, which is updated on
addition/removal of hrtimers.
This patch creates for_each_active_base(), which uses 'active_bases' to
iterate only over active bases.
This also updates code which iterates over clock-bases.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
kernel/time/hrtimer.c | 65 ++++++++++++++++++++++++++++++++-------------------
1 file changed, 41 insertions(+), 24 deletions(-)
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 3152f327c988..9da63e9ee63b 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -110,6 +110,31 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id)
}
+static inline int __next_bit(unsigned int active_bases, int bit)
+{
+ do {
+ if (active_bases & (1 << bit))
+ return bit;
+ } while (++bit < HRTIMER_MAX_CLOCK_BASES);
+
+ /* We should never reach here */
+ return 0;
+}
+
+/*
+ * for_each_active_base: iterate over all active clock bases
+ * @_bit: 'int' variable for internal purpose
+ * @_base: holds pointer to a active clock base
+ * @_cpu_base: cpu base to iterate on
+ * @_active_bases: 'unsigned int' variable for internal purpose
+ */
+#define for_each_active_base(_bit, _base, _cpu_base, _active_bases) \
+ for ((_active_bases) = (_cpu_base)->active_bases, (_bit) = -1; \
+ (_active_bases) && \
+ ((_bit) = __next_bit(_active_bases, ++_bit), \
+ (_base) = (_cpu_base)->clock_base + _bit); \
+ (_active_bases) &= ~(1 << (_bit)))
+
/*
* Get the coarse grained time at the softirq based on xtime and
* wall_to_monotonic.
@@ -443,19 +468,15 @@ static inline void debug_deactivate(struct hrtimer *timer)
#if defined(CONFIG_NO_HZ_COMMON) || defined(CONFIG_HIGH_RES_TIMERS)
static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base)
{
- struct hrtimer_clock_base *base = cpu_base->clock_base;
+ struct hrtimer_clock_base *base;
ktime_t expires, expires_next = { .tv64 = KTIME_MAX };
+ struct hrtimer *timer;
+ unsigned int active_bases;
int i;
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
- struct timerqueue_node *next;
- struct hrtimer *timer;
-
- next = timerqueue_getnext(&base->active);
- if (!next)
- continue;
-
- timer = container_of(next, struct hrtimer, node);
+ for_each_active_base(i, base, cpu_base, active_bases) {
+ timer = container_of(timerqueue_getnext(&base->active),
+ struct hrtimer, node);
expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
if (expires.tv64 < expires_next.tv64)
expires_next = expires;
@@ -1245,6 +1266,8 @@ void hrtimer_interrupt(struct clock_event_device *dev)
{
struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
ktime_t expires_next, now, entry_time, delta;
+ struct hrtimer_clock_base *base;
+ unsigned int active_bases;
int i, retries = 0;
BUG_ON(!cpu_base->hres_active);
@@ -1264,15 +1287,10 @@ void hrtimer_interrupt(struct clock_event_device *dev)
*/
cpu_base->expires_next.tv64 = KTIME_MAX;
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- struct hrtimer_clock_base *base;
+ for_each_active_base(i, base, cpu_base, active_bases) {
struct timerqueue_node *node;
ktime_t basenow;
- if (!(cpu_base->active_bases & (1 << i)))
- continue;
-
- base = cpu_base->clock_base + i;
basenow = ktime_add(now, base->offset);
while ((node = timerqueue_getnext(&base->active))) {
@@ -1435,16 +1453,13 @@ void hrtimer_run_queues(void)
struct timerqueue_node *node;
struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
struct hrtimer_clock_base *base;
+ unsigned int active_bases;
int index, gettime = 1;
if (hrtimer_hres_active())
return;
- for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
- base = &cpu_base->clock_base[index];
- if (!timerqueue_getnext(&base->active))
- continue;
-
+ for_each_active_base(index, base, cpu_base, active_bases) {
if (gettime) {
hrtimer_get_softirq_time(cpu_base);
gettime = 0;
@@ -1665,6 +1680,8 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
static void migrate_hrtimers(int scpu)
{
struct hrtimer_cpu_base *old_base, *new_base;
+ struct hrtimer_clock_base *clock_base;
+ unsigned int active_bases;
int i;
BUG_ON(cpu_online(scpu));
@@ -1680,9 +1697,9 @@ static void migrate_hrtimers(int scpu)
raw_spin_lock(&new_base->lock);
raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- migrate_hrtimer_list(&old_base->clock_base[i],
- &new_base->clock_base[i]);
+ for_each_active_base(i, clock_base, old_base, active_bases) {
+ migrate_hrtimer_list(clock_base,
+ &new_base->clock_base[clock_base->index]);
}
raw_spin_unlock(&old_base->lock);
--
2.3.0.rc0.44.ga94655d
next prev parent reply other threads:[~2015-04-07 2:11 UTC|newest]
Thread overview: 123+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-07 2:10 [PATCH V2 0/2] hrtimer: Iterate only over active clock-bases Viresh Kumar
2015-04-07 2:10 ` [PATCH V2 1/2] hrtimer: update '->active_bases' before calling hrtimer_force_reprogram() Viresh Kumar
2015-04-22 19:04 ` [tip:timers/core] hrtimer: Update active_bases " tip-bot for Viresh Kumar
2015-04-07 2:10 ` Viresh Kumar [this message]
2015-04-08 12:10 ` [PATCH V2 2/2] hrtimer: Iterate only over active clock-bases Peter Zijlstra
2015-04-08 20:11 ` Thomas Gleixner
2015-04-09 2:42 ` Viresh Kumar
2015-04-09 6:28 ` [PATCH] hrtimer: Replace cpu_base->active_bases with a direct check of the active list Ingo Molnar
2015-04-09 6:38 ` Ingo Molnar
2015-04-09 6:39 ` [PATCH] hrtimer: Only iterate over active bases in migrate_hrtimers() Ingo Molnar
2015-04-09 6:53 ` [PATCH] hrtimer: Replace timerqueue_getnext() uses with direct access to 'active.next' Ingo Molnar
2015-04-09 7:10 ` [PATCH] hrtimers: Use consistent variable names for timerqueue_node iterations Ingo Molnar
2015-04-09 6:57 ` [PATCH] hrtimer: Replace cpu_base->active_bases with a direct check of the active list Peter Zijlstra
2015-04-09 7:09 ` Ingo Molnar
2015-04-09 7:20 ` Ingo Molnar
2015-04-09 8:58 ` Thomas Gleixner
2015-04-09 8:58 ` Peter Zijlstra
2015-04-09 9:18 ` Thomas Gleixner
2015-04-09 9:31 ` Peter Zijlstra
2015-04-09 9:56 ` Thomas Gleixner
2015-04-13 5:53 ` Preeti U Murthy
2015-04-13 7:53 ` Thomas Gleixner
2015-04-09 8:03 ` Peter Zijlstra
2015-04-09 8:10 ` Ingo Molnar
2015-04-09 8:53 ` Thomas Gleixner
2015-04-09 9:18 ` Ingo Molnar
2015-04-14 21:08 [patch 00/39] hrtimer/tick: Optimizations, cleanups and solutions for various issues Thomas Gleixner
2015-04-14 21:08 ` [patch 01/39] hrtimer: Update active_bases before calling hrtimer_force_reprogram() Thomas Gleixner
2015-04-14 21:08 ` [patch 02/39] hrtimer: Get rid of the resolution field in hrtimer_clock_base Thomas Gleixner
2015-04-15 6:29 ` Frans Klaver
2015-04-15 6:32 ` Frans Klaver
2015-04-20 8:34 ` Preeti U Murthy
2015-04-22 19:05 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 03/39] net: sched: Use hrtimer_resolution instead of hrtimer_get_res() Thomas Gleixner
2015-04-16 16:04 ` David Miller
2015-04-22 19:05 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 04/39] sound: " Thomas Gleixner
2015-04-16 8:07 ` Takashi Iwai
2015-04-16 9:08 ` Thomas Gleixner
2015-04-22 19:05 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 05/39] hrtimer: Get rid " Thomas Gleixner
2015-04-22 19:05 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 06/39] hrtimer: Make the statistics fields smaller Thomas Gleixner
2015-04-22 19:06 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 07/39] hrtimer: Get rid of softirq time Thomas Gleixner
2015-04-22 19:06 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 08/39] hrtimer: Make offset update smarter Thomas Gleixner
2015-04-20 9:30 ` Preeti U Murthy
2015-04-22 19:06 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 09/39] hrtimer: Use a bits for various boolean indicators Thomas Gleixner
2015-04-22 19:07 ` [tip:timers/core] hrtimer: Use " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 10/39] hrtimer: Use cpu_base->active_base for hotpath iterators Thomas Gleixner
2015-04-20 11:16 ` Preeti U Murthy
2015-04-21 11:53 ` Thomas Gleixner
2015-04-22 3:13 ` Preeti U Murthy
2015-04-22 19:07 ` [tip:timers/core] hrtimer: Use cpu_base-> active_base " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 11/39] hrtimer: Cache line align the hrtimer cpu base Thomas Gleixner
2015-04-22 19:07 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 12/39] hrtimer: Align the hrtimer clock bases as well Thomas Gleixner
2015-04-22 19:07 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 13/39] timerqueue: Let timerqueue_add/del return information Thomas Gleixner
2015-04-22 19:08 ` [tip:timers/core] timerqueue: Let timerqueue_add/ del " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 14/39] hrtimer: Make use of timerqueue_add/del return values Thomas Gleixner
2015-04-22 19:08 ` [tip:timers/core] hrtimer: Make use of timerqueue_add/ del " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 15/39] hrtimer: Keep pointer to first timer and simplify __remove_hrtimer() Thomas Gleixner
2015-04-22 19:08 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 16/39] hrtimer: Get rid of hrtimer softirq Thomas Gleixner
2015-04-22 19:09 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 17/39] tick: sched: Remove hrtimer_active() checks Thomas Gleixner
2015-04-16 13:37 ` Frederic Weisbecker
2015-04-22 19:09 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 18/39] tick: sched: Force tick interrupt and get rid of softirq magic Thomas Gleixner
2015-04-22 14:22 ` Frederic Weisbecker
2015-04-22 14:32 ` Thomas Gleixner
2015-04-23 11:47 ` Frederic Weisbecker
2015-04-23 13:07 ` Thomas Gleixner
2015-04-23 16:14 ` Frederic Weisbecker
2015-04-22 19:09 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 19/39] tick: sched: Restructure code Thomas Gleixner
2015-04-22 19:09 ` [tip:timers/core] tick: Sched: " tip-bot for Thomas Gleixner
2015-04-14 21:08 ` [patch 20/39] tick: nohz: Rework next timer evaluation Thomas Gleixner
2015-04-16 16:42 ` Paul E. McKenney
2015-04-21 12:04 ` Thomas Gleixner
2015-04-22 19:10 ` [tip:timers/core] tick: Nohz: " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 21/39] x86: perf: Use hrtimer_start() Thomas Gleixner
2015-04-22 19:10 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 22/39] x86: perf: uncore: " Thomas Gleixner
2015-04-22 19:10 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 23/39] perf: core: " Thomas Gleixner
2015-04-22 19:11 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 24/39] sched: core: Use hrtimer_start[_expires]() Thomas Gleixner
2015-04-22 19:11 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 25/39] sched: deadline: Use hrtimer_start() Thomas Gleixner
2015-04-22 19:11 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 26/39] hrtimer: Get rid of __hrtimer_start_range_ns() Thomas Gleixner
2015-04-22 19:11 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 27/39] hrtimer: Make hrtimer_start() a inline wrapper Thomas Gleixner
2015-04-22 19:12 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 28/39] hrtimer: Remove bogus hrtimer_active() check Thomas Gleixner
2015-04-22 19:12 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 29/39] hrtimer: Rmove " Thomas Gleixner
2015-04-22 19:12 ` [tip:timers/core] futex: Remove " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 30/39] rtmutex: " Thomas Gleixner
2015-04-22 19:13 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 31/39] net: core: pktgen: " Thomas Gleixner
2015-04-16 16:04 ` David Miller
2015-04-22 19:13 ` [tip:timers/core] net: core: pktgen: Remove bogus hrtimer_active( ) check tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 32/39] alarmtimer: Get rid of unused return value Thomas Gleixner
2015-04-22 19:13 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 34/39] tick: broadcast-hrtimer: Remove overly clever return value abuse Thomas Gleixner
2015-04-17 10:33 ` Preeti U Murthy
2015-04-22 19:13 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 35/39] hrtimer: Remove hrtimer_start() return value Thomas Gleixner
2015-04-22 19:14 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 36/39] hrtimer: Avoid locking in hrtimer_cancel() if timer not active Thomas Gleixner
2015-04-22 19:14 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 37/39] staging: ozwpan: Remove hrtimer_active() check Thomas Gleixner
2015-04-14 21:09 ` [patch 38/39] timer: Remove pointless return value of do_usleep_range() Thomas Gleixner
2015-04-22 19:14 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-14 21:09 ` [patch 39/39] timer: Put usleep_range into the __sched section Thomas Gleixner
2015-04-22 19:14 ` [tip:timers/core] " tip-bot for Thomas Gleixner
[not found] ` <20150414203503.322172417@linutronix.de>
2015-04-14 21:38 ` [patch 33/39] power: reset: ltc2952: Remove bogus hrtimer_start() return value checks Frans Klaver
2015-04-30 15:49 ` Sebastian Reichel
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