diff options
| -rw-r--r-- | include/linux/tick.h | 7 | ||||
| -rw-r--r-- | kernel/compat.c | 24 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 14 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 5 |
4 files changed, 39 insertions, 11 deletions
diff --git a/include/linux/tick.h b/include/linux/tick.h index 059052306831..9a82c7dc3fdd 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -183,13 +183,8 @@ static inline bool tick_nohz_full_cpu(int cpu) extern void tick_nohz_init(void); extern void __tick_nohz_full_check(void); +extern void tick_nohz_full_kick(void); extern void tick_nohz_full_kick_cpu(int cpu); - -static inline void tick_nohz_full_kick(void) -{ - tick_nohz_full_kick_cpu(smp_processor_id()); -} - extern void tick_nohz_full_kick_all(void); extern void __tick_nohz_task_switch(struct task_struct *tsk); #else diff --git a/kernel/compat.c b/kernel/compat.c index 633394f442f8..ebb3c369d03d 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -226,7 +226,7 @@ static long compat_nanosleep_restart(struct restart_block *restart) ret = hrtimer_nanosleep_restart(restart); set_fs(oldfs); - if (ret) { + if (ret == -ERESTART_RESTARTBLOCK) { rmtp = restart->nanosleep.compat_rmtp; if (rmtp && compat_put_timespec(&rmt, rmtp)) @@ -256,7 +256,26 @@ COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC); set_fs(oldfs); - if (ret) { + /* + * hrtimer_nanosleep() can only return 0 or + * -ERESTART_RESTARTBLOCK here because: + * + * - we call it with HRTIMER_MODE_REL and therefor exclude the + * -ERESTARTNOHAND return path. + * + * - we supply the rmtp argument from the task stack (due to + * the necessary compat conversion. So the update cannot + * fail, which excludes the -EFAULT return path as well. If + * it fails nevertheless we have a bigger problem and wont + * reach this place anymore. + * + * - if the return value is 0, we do not have to update rmtp + * because there is no remaining time. + * + * We check for -ERESTART_RESTARTBLOCK nevertheless if the + * core implementation decides to return random nonsense. + */ + if (ret == -ERESTART_RESTARTBLOCK) { struct restart_block *restart = ¤t_thread_info()->restart_block; @@ -266,7 +285,6 @@ COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp, if (rmtp && compat_put_timespec(&rmt, rmtp)) return -EFAULT; } - return ret; } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 99aa6ee3908f..f654a8a298fa 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -225,6 +225,20 @@ static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = { }; /* + * Kick this CPU if it's full dynticks in order to force it to + * re-evaluate its dependency on the tick and restart it if necessary. + * This kick, unlike tick_nohz_full_kick_cpu() and tick_nohz_full_kick_all(), + * is NMI safe. + */ +void tick_nohz_full_kick(void) +{ + if (!tick_nohz_full_cpu(smp_processor_id())) + return; + + irq_work_queue(&__get_cpu_var(nohz_full_kick_work)); +} + +/* * Kick the CPU if it's full dynticks in order to force it to * re-evaluate its dependency on the tick and restart it if necessary. */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index fb4a9c2cf8d9..ec1791fae965 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -442,11 +442,12 @@ static void timekeeping_update(struct timekeeper *tk, unsigned int action) tk->ntp_error = 0; ntp_clear(); } - update_vsyscall(tk); - update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET); tk_update_ktime_data(tk); + update_vsyscall(tk); + update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET); + if (action & TK_MIRROR) memcpy(&shadow_timekeeper, &tk_core.timekeeper, sizeof(tk_core.timekeeper)); |