From 48cf76f7104f655bbd48a75c7759dce82c3e1ab6 Mon Sep 17 00:00:00 2001 From: Torben Hohn Date: Thu, 27 Jan 2011 15:59:05 +0100 Subject: time: Provide get_xtime_and_monotonic_offset() The hrtimer code accesses timekeeping variables under xtime_lock. Provide a sensible accessor function and use it. [ tglx: Removed the conditionals, unused variable, fixed codingstyle and massaged changelog ] Signed-off-by: Torben Hohn Cc: Peter Zijlstra Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145905.23248.30458.stgit@localhost> Signed-off-by: Thomas Gleixner --- kernel/hrtimer.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'kernel/hrtimer.c') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 0c8d7c04861..57c4d33c9a9 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -85,13 +85,8 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base) { ktime_t xtim, tomono; struct timespec xts, tom; - unsigned long seq; - do { - seq = read_seqbegin(&xtime_lock); - xts = __current_kernel_time(); - tom = __get_wall_to_monotonic(); - } while (read_seqretry(&xtime_lock, seq)); + get_xtime_and_monotonic_offset(&xts, &tom); xtim = timespec_to_ktime(xts); tomono = timespec_to_ktime(tom); @@ -612,15 +607,11 @@ static void retrigger_next_event(void *arg) { struct hrtimer_cpu_base *base; struct timespec realtime_offset, wtm; - unsigned long seq; if (!hrtimer_hres_active()) return; - do { - seq = read_seqbegin(&xtime_lock); - wtm = __get_wall_to_monotonic(); - } while (read_seqretry(&xtime_lock, seq)); + get_xtime_and_monotonic_offset(&realtime_offset, &wtm); set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec); base = &__get_cpu_var(hrtimer_bases); -- cgit v1.2.3 From e06383db9ec591696a06654257474b85bac1f8cb Mon Sep 17 00:00:00 2001 From: John Stultz Date: Tue, 14 Dec 2010 19:37:07 -0800 Subject: hrtimers: extend hrtimer base code to handle more then 2 clockids MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The hrtimer code is written mainly with CLOCK_REALTIME and CLOCK_MONOTONIC in mind. These are clockids 0 and 1 resepctively. However, if we are to introduce any new hrtimer bases, using new clockids, we have to skip the cputimers (clockids 2,3) as well as other clockids that may not impelement timers. This patch adds a little bit of indirection between the clockid and the base, so that we can extend the base by one when we add a new clockid at number 7 or so. CC: Jamie Lokier CC: Thomas Gleixner CC: Alexander Shishkin CC: Arve Hjønnevåg Signed-off-by: John Stultz --- kernel/hrtimer.c | 40 +++++++++++++++++++++++++++------------- 1 file changed, 27 insertions(+), 13 deletions(-) (limited to 'kernel/hrtimer.c') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 57c4d33c9a9..ca99e245460 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -53,11 +53,10 @@ /* * The timer bases: * - * Note: If we want to add new timer bases, we have to skip the two - * clock ids captured by the cpu-timers. We do this by holding empty - * entries rather than doing math adjustment of the clock ids. - * This ensures that we capture erroneous accesses to these clock ids - * rather than moving them into the range of valid clock id's. + * There are more clockids then hrtimer bases. Thus, we index + * into the timer bases by the hrtimer_base_type enum. When trying + * to reach a base using a clockid, hrtimer_clockid_to_base() + * is used to convert from clockid to the proper hrtimer_base_type. */ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = { @@ -77,6 +76,14 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = } }; +static int hrtimer_clock_to_base_table[MAX_CLOCKS]; + +static inline int hrtimer_clockid_to_base(clockid_t clock_id) +{ + return hrtimer_clock_to_base_table[clock_id]; +} + + /* * Get the coarse grained time at the softirq based on xtime and * wall_to_monotonic. @@ -90,8 +97,8 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base) xtim = timespec_to_ktime(xts); tomono = timespec_to_ktime(tom); - base->clock_base[CLOCK_REALTIME].softirq_time = xtim; - base->clock_base[CLOCK_MONOTONIC].softirq_time = + base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim; + base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = ktime_add(xtim, tomono); } @@ -179,10 +186,11 @@ switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base, struct hrtimer_cpu_base *new_cpu_base; int this_cpu = smp_processor_id(); int cpu = hrtimer_get_target(this_cpu, pinned); + int basenum = hrtimer_clockid_to_base(base->index); again: new_cpu_base = &per_cpu(hrtimer_bases, cpu); - new_base = &new_cpu_base->clock_base[base->index]; + new_base = &new_cpu_base->clock_base[basenum]; if (base != new_base) { /* @@ -618,7 +626,7 @@ static void retrigger_next_event(void *arg) /* Adjust CLOCK_REALTIME offset */ raw_spin_lock(&base->lock); - base->clock_base[CLOCK_REALTIME].offset = + base->clock_base[HRTIMER_BASE_REALTIME].offset = timespec_to_ktime(realtime_offset); hrtimer_force_reprogram(base, 0); @@ -716,8 +724,8 @@ static int hrtimer_switch_to_hres(void) return 0; } base->hres_active = 1; - base->clock_base[CLOCK_REALTIME].resolution = KTIME_HIGH_RES; - base->clock_base[CLOCK_MONOTONIC].resolution = KTIME_HIGH_RES; + base->clock_base[HRTIMER_BASE_REALTIME].resolution = KTIME_HIGH_RES; + base->clock_base[HRTIMER_BASE_MONOTONIC].resolution = KTIME_HIGH_RES; tick_setup_sched_timer(); @@ -1112,6 +1120,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, enum hrtimer_mode mode) { struct hrtimer_cpu_base *cpu_base; + int base; memset(timer, 0, sizeof(struct hrtimer)); @@ -1120,7 +1129,8 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, if (clock_id == CLOCK_REALTIME && mode != HRTIMER_MODE_ABS) clock_id = CLOCK_MONOTONIC; - timer->base = &cpu_base->clock_base[clock_id]; + base = hrtimer_clockid_to_base(clock_id); + timer->base = &cpu_base->clock_base[base]; hrtimer_init_timer_hres(timer); timerqueue_init(&timer->node); @@ -1156,9 +1166,10 @@ EXPORT_SYMBOL_GPL(hrtimer_init); int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) { struct hrtimer_cpu_base *cpu_base; + int base = hrtimer_clockid_to_base(which_clock); cpu_base = &__raw_get_cpu_var(hrtimer_bases); - *tp = ktime_to_timespec(cpu_base->clock_base[which_clock].resolution); + *tp = ktime_to_timespec(cpu_base->clock_base[base].resolution); return 0; } @@ -1705,6 +1716,9 @@ static struct notifier_block __cpuinitdata hrtimers_nb = { void __init hrtimers_init(void) { + hrtimer_clock_to_base_table[CLOCK_REALTIME] = HRTIMER_BASE_REALTIME; + hrtimer_clock_to_base_table[CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC; + hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE, (void *)(long)smp_processor_id()); register_cpu_notifier(&hrtimers_nb); -- cgit v1.2.3 From 314ac37150011ebb398f522db528d2dbcc611189 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Mon, 14 Feb 2011 18:43:08 -0800 Subject: time: Extend get_xtime_and_monotonic_offset() to also return sleep MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Extend get_xtime_and_monotonic_offset to get_xtime_and_monotonic_and_sleep_offset(). CC: Jamie Lokier CC: Thomas Gleixner CC: Alexander Shishkin CC: Arve Hjønnevåg Signed-off-by: John Stultz --- kernel/hrtimer.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'kernel/hrtimer.c') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index ca99e245460..e8bf3ad9906 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -91,9 +91,9 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id) static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base) { ktime_t xtim, tomono; - struct timespec xts, tom; + struct timespec xts, tom, slp; - get_xtime_and_monotonic_offset(&xts, &tom); + get_xtime_and_monotonic_and_sleep_offset(&xts, &tom, &slp); xtim = timespec_to_ktime(xts); tomono = timespec_to_ktime(tom); @@ -614,12 +614,13 @@ static int hrtimer_reprogram(struct hrtimer *timer, static void retrigger_next_event(void *arg) { struct hrtimer_cpu_base *base; - struct timespec realtime_offset, wtm; + struct timespec realtime_offset, wtm, sleep; if (!hrtimer_hres_active()) return; - get_xtime_and_monotonic_offset(&realtime_offset, &wtm); + get_xtime_and_monotonic_and_sleep_offset(&realtime_offset, &wtm, + &sleep); set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec); base = &__get_cpu_var(hrtimer_bases); -- cgit v1.2.3 From 70a08cca1227dc31c784ec930099a4417a06e7d0 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Tue, 15 Feb 2011 10:45:16 -0800 Subject: timers: Add CLOCK_BOOTTIME hrtimer base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit CLOCK_MONOTONIC stops while the system is in suspend. This is because to applications system suspend is invisible. However, there is a growing set of applications that are wanting to be suspend-aware, but do not want to deal with the complications of CLOCK_REALTIME (which might jump around if settimeofday is called). For these applications, I propose a new clockid: CLOCK_BOOTTIME. CLOCK_BOOTTIME is idential to CLOCK_MONOTONIC, except it also includes any time spent in suspend. This patch add hrtimer base for CLOCK_BOOTTIME, using get_monotonic_boottime/ktime_get_boottime, to allow in kernel users to set timers against. CC: Jamie Lokier CC: Thomas Gleixner CC: Alexander Shishkin CC: Arve Hjønnevåg Signed-off-by: John Stultz --- kernel/hrtimer.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'kernel/hrtimer.c') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index e8bf3ad9906..4c53af18734 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -73,6 +73,11 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = .get_time = &ktime_get, .resolution = KTIME_LOW_RES, }, + { + .index = CLOCK_BOOTTIME, + .get_time = &ktime_get_boottime, + .resolution = KTIME_LOW_RES, + }, } }; @@ -90,16 +95,17 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id) */ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base) { - ktime_t xtim, tomono; + ktime_t xtim, mono, boot; struct timespec xts, tom, slp; get_xtime_and_monotonic_and_sleep_offset(&xts, &tom, &slp); xtim = timespec_to_ktime(xts); - tomono = timespec_to_ktime(tom); + mono = ktime_add(xtim, timespec_to_ktime(tom)); + boot = ktime_add(mono, timespec_to_ktime(slp)); base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim; - base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = - ktime_add(xtim, tomono); + base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono; + base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot; } /* @@ -727,6 +733,7 @@ static int hrtimer_switch_to_hres(void) base->hres_active = 1; base->clock_base[HRTIMER_BASE_REALTIME].resolution = KTIME_HIGH_RES; base->clock_base[HRTIMER_BASE_MONOTONIC].resolution = KTIME_HIGH_RES; + base->clock_base[HRTIMER_BASE_BOOTTIME].resolution = KTIME_HIGH_RES; tick_setup_sched_timer(); @@ -1719,6 +1726,7 @@ void __init hrtimers_init(void) { hrtimer_clock_to_base_table[CLOCK_REALTIME] = HRTIMER_BASE_REALTIME; hrtimer_clock_to_base_table[CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC; + hrtimer_clock_to_base_table[CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME; hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE, (void *)(long)smp_processor_id()); -- cgit v1.2.3 From 5cd10e7946d28cfc42442fee2e6c757e244d756e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 2 Mar 2011 16:58:30 +0100 Subject: hrtimer: Update base[CLOCK_BOOTTIME].offset correctly We calculate the current time of each clock base by adding an offset to clock_monotonic. The offset for the clock bases is set in retrigger_next_event() which is called when we switch a cpu to highres mode or when the clock was set. Add the missing update for clock boottime. Signed-off-by: Thomas Gleixner Cc: John Stultz --- kernel/hrtimer.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/hrtimer.c') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 4c53af18734..f679a2d0872 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -635,6 +635,8 @@ static void retrigger_next_event(void *arg) raw_spin_lock(&base->lock); base->clock_base[HRTIMER_BASE_REALTIME].offset = timespec_to_ktime(realtime_offset); + base->clock_base[HRTIMER_BASE_BOOTTIME].offset = + timespec_to_ktime(sleep); hrtimer_force_reprogram(base, 0); raw_spin_unlock(&base->lock); -- cgit v1.2.3 From a9e7acfff0a279792918b7b0de74106e576e9988 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 10 Mar 2011 19:12:24 +0100 Subject: hrtimer: Remove empty hrtimer_init_hres_timer() Leftover from earlier implementation. All empty, remove it. Signed-off-by: Thomas Gleixner --- kernel/hrtimer.c | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'kernel/hrtimer.c') diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index f679a2d0872..63fb74972b7 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -680,14 +680,6 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) base->hres_active = 0; } -/* - * Initialize the high resolution related parts of a hrtimer - */ -static inline void hrtimer_init_timer_hres(struct hrtimer *timer) -{ -} - - /* * When High resolution timers are active, try to reprogram. Note, that in case * the state has HRTIMER_STATE_CALLBACK set, no reprogramming and no expiry @@ -759,7 +751,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, return 0; } static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { } -static inline void hrtimer_init_timer_hres(struct hrtimer *timer) { } #endif /* CONFIG_HIGH_RES_TIMERS */ @@ -1141,7 +1132,6 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, base = hrtimer_clockid_to_base(clock_id); timer->base = &cpu_base->clock_base[base]; - hrtimer_init_timer_hres(timer); timerqueue_init(&timer->node); #ifdef CONFIG_TIMER_STATS -- cgit v1.2.3