diff options
Diffstat (limited to 'kernel/posix-cpu-timers.c')
-rw-r--r-- | kernel/posix-cpu-timers.c | 64 |
1 files changed, 30 insertions, 34 deletions
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index e6389f9..03c5d6c3 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -260,30 +260,43 @@ static int cpu_clock_sample_group(const clockid_t which_clock, return 0; } +static int posix_cpu_clock_get_task(struct task_struct *tsk, + const clockid_t which_clock, + struct timespec *tp) +{ + int err = -EINVAL; + unsigned long long rtn; + + if (CPUCLOCK_PERTHREAD(which_clock)) { + if (same_thread_group(tsk, current)) + err = cpu_clock_sample(which_clock, tsk, &rtn); + } else { + read_lock(&tasklist_lock); + + if (tsk->sighand && (tsk == current || thread_group_leader(tsk))) + err = cpu_clock_sample_group(which_clock, tsk, &rtn); + + read_unlock(&tasklist_lock); + } + + if (!err) + sample_to_timespec(which_clock, rtn, tp); + + return err; +} + static int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) { const pid_t pid = CPUCLOCK_PID(which_clock); - int error = -EINVAL; - unsigned long long rtn; + int err = -EINVAL; if (pid == 0) { /* * Special case constant value for our own clocks. * We don't have to do any lookup to find ourselves. */ - if (CPUCLOCK_PERTHREAD(which_clock)) { - /* - * Sampling just ourselves we can do with no locking. - */ - error = cpu_clock_sample(which_clock, - current, &rtn); - } else { - read_lock(&tasklist_lock); - error = cpu_clock_sample_group(which_clock, - current, &rtn); - read_unlock(&tasklist_lock); - } + err = posix_cpu_clock_get_task(current, which_clock, tp); } else { /* * Find the given PID, and validate that the caller @@ -292,29 +305,12 @@ static int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) struct task_struct *p; rcu_read_lock(); p = find_task_by_vpid(pid); - if (p) { - if (CPUCLOCK_PERTHREAD(which_clock)) { - if (same_thread_group(p, current)) { - error = cpu_clock_sample(which_clock, - p, &rtn); - } - } else { - read_lock(&tasklist_lock); - if (thread_group_leader(p) && p->sighand) { - error = - cpu_clock_sample_group(which_clock, - p, &rtn); - } - read_unlock(&tasklist_lock); - } - } + if (p) + err = posix_cpu_clock_get_task(p, which_clock, tp); rcu_read_unlock(); } - if (error) - return error; - sample_to_timespec(which_clock, rtn, tp); - return 0; + return err; } |