posix-timers: Introduce clockid_to_kclock()

New function to find the kclock for a given clockid.

Returns a pointer to clock_posix_cpu if clockid < 0. If clockid >=
MAXCLOCK or if the clock_getres pointer is not set it returns
NULL. For valid clocks it returns a pointer to the matching
posix_clock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Acked-by: Richard Cochran <richard.cochran@omicron.at>
LKML-Reference: <20110201134417.938447839@linutronix.de>
This commit is contained in:
Thomas Gleixner 2011-02-01 13:51:09 +00:00
parent 1976945eea
commit cc785ac22b
1 changed files with 10 additions and 0 deletions

View File

@ -531,6 +531,16 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
kmem_cache_free(posix_timers_cache, tmr);
}
static struct k_clock *clockid_to_kclock(const clockid_t id)
{
if (id < 0)
return &clock_posix_cpu;
if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres)
return NULL;
return &posix_clocks[id];
}
/* Create a POSIX.1b interval timer. */
SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,