OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

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 <tglx@linutronix.de>
This commit is contained in:
Thomas Gleixner 2011-03-10 18:26:33 +01:00
parent 5cd10e7946
commit 53370d2e8c
1 changed files with 11 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
include/linux/hrtimer.h
View File

@ -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)
{