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 --- include/linux/hrtimer.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include/linux/hrtimer.h') diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index f376ddc64c4d..20b8e6601a04 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -148,7 +148,11 @@ struct hrtimer_clock_base { #endif }; -#define HRTIMER_MAX_CLOCK_BASES 2 +enum hrtimer_base_type { + HRTIMER_BASE_REALTIME, + HRTIMER_BASE_MONOTONIC, + HRTIMER_MAX_CLOCK_BASES, +}; /* * struct hrtimer_cpu_base - the per cpu clock bases -- cgit v1.2.2 From abb3a4ea2e0ea7114a4475745da2f32bd9ad5b73 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Mon, 14 Feb 2011 17:52:09 -0800 Subject: time: Introduce get_monotonic_boottime and ktime_get_boottime MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds new functions that return the monotonic time since boot (in other words, CLOCK_MONOTONIC + suspend time). CC: Jamie Lokier CC: Thomas Gleixner CC: Alexander Shishkin CC: Arve Hjønnevåg Signed-off-by: John Stultz --- include/linux/hrtimer.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/hrtimer.h') diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 20b8e6601a04..7a9e7ee0f35c 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -312,6 +312,7 @@ static inline int hrtimer_is_hres_active(struct hrtimer *timer) extern ktime_t ktime_get(void); extern ktime_t ktime_get_real(void); +extern ktime_t ktime_get_boottime(void); DECLARE_PER_CPU(struct tick_device, tick_cpu_device); -- cgit v1.2.2 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 --- include/linux/hrtimer.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/hrtimer.h') diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 7a9e7ee0f35c..6bc1804bfbfa 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -151,6 +151,7 @@ struct hrtimer_clock_base { enum hrtimer_base_type { HRTIMER_BASE_REALTIME, HRTIMER_BASE_MONOTONIC, + HRTIMER_BASE_BOOTTIME, HRTIMER_MAX_CLOCK_BASES, }; -- cgit v1.2.2 From 53370d2e8c0382e3e2aa76def93365ed674e7fc7 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 10 Mar 2011 18:26:33 +0100 Subject: hrtimer: Update hrtimer->state documentation We changed some of the state bits and combinations thereof over time, but never updated the documentation. Signed-off-by: Thomas Gleixner --- include/linux/hrtimer.h | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'include/linux/hrtimer.h') diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 6bc1804bfbfa..62f500c724f9 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -54,11 +54,13 @@ enum hrtimer_restart { * 0x00 inactive * 0x01 enqueued into rbtree * 0x02 callback function running + * 0x04 timer is migrated to another cpu * * Special cases: * 0x03 callback function running and enqueued * (was requeued on another CPU) - * 0x09 timer was migrated on CPU hotunplug + * 0x05 timer was migrated on CPU hotunplug + * * The "callback function running and enqueued" status is only possible on * SMP. It happens for example when a posix timer expired and the callback * queued a signal. Between dropping the lock which protects the posix timer @@ -67,8 +69,11 @@ enum hrtimer_restart { * as otherwise the timer could be removed before the softirq code finishes the * the handling of the timer. * - * The HRTIMER_STATE_ENQUEUED bit is always or'ed to the current state to - * preserve the HRTIMER_STATE_CALLBACK bit in the above scenario. + * The HRTIMER_STATE_ENQUEUED bit is always or'ed to the current state + * to preserve the HRTIMER_STATE_CALLBACK in the above scenario. This + * also affects HRTIMER_STATE_MIGRATE where the preservation is not + * necessary. HRTIMER_STATE_MIGRATE is cleared after the timer is + * enqueued on the new cpu. * * All state transitions are protected by cpu_base->lock. */ @@ -376,8 +381,9 @@ extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp); extern ktime_t hrtimer_get_next_event(void); /* - * A timer is active, when it is enqueued into the rbtree or the callback - * function is running. + * A timer is active, when it is enqueued into the rbtree or the + * callback function is running or it's in the state of being migrated + * to another cpu. */ static inline int hrtimer_active(const struct hrtimer *timer) { -- cgit v1.2.2