1 files changed, 2 insertions, 193 deletions
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 06f0bc1db6d9..a5860bf6d16f 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -37,7 +37,6 @@
 #include <linux/tick.h>
 #include <linux/kallsyms.h>
 #include <linux/irq_work.h>
-#include <linux/sched/signal.h>
 #include <linux/sched/sysctl.h>
 #include <linux/sched/nohz.h>
 #include <linux/sched/debug.h>
@@ -2422,7 +2421,8 @@ static inline void __run_timers(struct timer_base *base)
 
 static void __run_timer_base(struct timer_base *base)
 {
-	if (time_before(jiffies, base->next_expiry))
+	/* Can race against a remote CPU updating next_expiry under the lock */
+	if (time_before(jiffies, READ_ONCE(base->next_expiry)))
 		return;
 
 	timer_base_lock_expiry(base);
@@ -2526,141 +2526,6 @@ void update_process_times(int user_tick)
 		run_posix_cpu_timers();
 }
 
-/*
- * Since schedule_timeout()'s timer is defined on the stack, it must store
- * the target task on the stack as well.
- */
-struct process_timer {
-	struct timer_list timer;
-	struct task_struct *task;
-};
-
-static void process_timeout(struct timer_list *t)
-{
-	struct process_timer *timeout = from_timer(timeout, t, timer);
-
-	wake_up_process(timeout->task);
-}
-
-/**
- * schedule_timeout - sleep until timeout
- * @timeout: timeout value in jiffies
- *
- * Make the current task sleep until @timeout jiffies have elapsed.
- * The function behavior depends on the current task state
- * (see also set_current_state() description):
- *
- * %TASK_RUNNING - the scheduler is called, but the task does not sleep
- * at all. That happens because sched_submit_work() does nothing for
- * tasks in %TASK_RUNNING state.
- *
- * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to
- * pass before the routine returns unless the current task is explicitly
- * woken up, (e.g. by wake_up_process()).
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task or the current task is explicitly woken
- * up.
- *
- * The current task state is guaranteed to be %TASK_RUNNING when this
- * routine returns.
- *
- * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule
- * the CPU away without a bound on the timeout. In this case the return
- * value will be %MAX_SCHEDULE_TIMEOUT.
- *
- * Returns 0 when the timer has expired otherwise the remaining time in
- * jiffies will be returned. In all cases the return value is guaranteed
- * to be non-negative.
- */
-signed long __sched schedule_timeout(signed long timeout)
-{
-	struct process_timer timer;
-	unsigned long expire;
-
-	switch (timeout)
-	{
-	case MAX_SCHEDULE_TIMEOUT:
-		/*
-		 * These two special cases are useful to be comfortable
-		 * in the caller. Nothing more. We could take
-		 * MAX_SCHEDULE_TIMEOUT from one of the negative value
-		 * but I' d like to return a valid offset (>=0) to allow
-		 * the caller to do everything it want with the retval.
-		 */
-		schedule();
-		goto out;
-	default:
-		/*
-		 * Another bit of PARANOID. Note that the retval will be
-		 * 0 since no piece of kernel is supposed to do a check
-		 * for a negative retval of schedule_timeout() (since it
-		 * should never happens anyway). You just have the printk()
-		 * that will tell you if something is gone wrong and where.
-		 */
-		if (timeout < 0) {
-			printk(KERN_ERR "schedule_timeout: wrong timeout "
-				"value %lx\n", timeout);
-			dump_stack();
-			__set_current_state(TASK_RUNNING);
-			goto out;
-		}
-	}
-
-	expire = timeout + jiffies;
-
-	timer.task = current;
-	timer_setup_on_stack(&timer.timer, process_timeout, 0);
-	__mod_timer(&timer.timer, expire, MOD_TIMER_NOTPENDING);
-	schedule();
-	del_timer_sync(&timer.timer);
-
-	/* Remove the timer from the object tracker */
-	destroy_timer_on_stack(&timer.timer);
-
-	timeout = expire - jiffies;
-
- out:
-	return timeout < 0 ? 0 : timeout;
-}
-EXPORT_SYMBOL(schedule_timeout);
-
-/*
- * We can use __set_current_state() here because schedule_timeout() calls
- * schedule() unconditionally.
- */
-signed long __sched schedule_timeout_interruptible(signed long timeout)
-{
-	__set_current_state(TASK_INTERRUPTIBLE);
-	return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_interruptible);
-
-signed long __sched schedule_timeout_killable(signed long timeout)
-{
-	__set_current_state(TASK_KILLABLE);
-	return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_killable);
-
-signed long __sched schedule_timeout_uninterruptible(signed long timeout)
-{
-	__set_current_state(TASK_UNINTERRUPTIBLE);
-	return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_uninterruptible);
-
-/*
- * Like schedule_timeout_uninterruptible(), except this task will not contribute
- * to load average.
- */
-signed long __sched schedule_timeout_idle(signed long timeout)
-{
-	__set_current_state(TASK_IDLE);
-	return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_idle);
-
 #ifdef CONFIG_HOTPLUG_CPU
 static void migrate_timer_list(struct timer_base *new_base, struct hlist_head *head)
 {
@@ -2757,59 +2622,3 @@ void __init init_timers(void)
 	posix_cputimers_init_work();
 	open_softirq(TIMER_SOFTIRQ, run_timer_softirq);
 }
-
-/**
- * msleep - sleep safely even with waitqueue interruptions
- * @msecs: Time in milliseconds to sleep for
- */
-void msleep(unsigned int msecs)
-{
-	unsigned long timeout = msecs_to_jiffies(msecs);
-
-	while (timeout)
-		timeout = schedule_timeout_uninterruptible(timeout);
-}
-
-EXPORT_SYMBOL(msleep);
-
-/**
- * msleep_interruptible - sleep waiting for signals
- * @msecs: Time in milliseconds to sleep for
- */
-unsigned long msleep_interruptible(unsigned int msecs)
-{
-	unsigned long timeout = msecs_to_jiffies(msecs);
-
-	while (timeout && !signal_pending(current))
-		timeout = schedule_timeout_interruptible(timeout);
-	return jiffies_to_msecs(timeout);
-}
-
-EXPORT_SYMBOL(msleep_interruptible);
-
-/**
- * usleep_range_state - Sleep for an approximate time in a given state
- * @min:	Minimum time in usecs to sleep
- * @max:	Maximum time in usecs to sleep
- * @state:	State of the current task that will be while sleeping
- *
- * In non-atomic context where the exact wakeup time is flexible, use
- * usleep_range_state() instead of udelay().  The sleep improves responsiveness
- * by avoiding the CPU-hogging busy-wait of udelay(), and the range reduces
- * power usage by allowing hrtimers to take advantage of an already-
- * scheduled interrupt instead of scheduling a new one just for this sleep.
- */
-void __sched usleep_range_state(unsigned long min, unsigned long max,
-				unsigned int state)
-{
-	ktime_t exp = ktime_add_us(ktime_get(), min);
-	u64 delta = (u64)(max - min) * NSEC_PER_USEC;
-
-	for (;;) {
-		__set_current_state(state);
-		/* Do not return before the requested sleep time has elapsed */
-		if (!schedule_hrtimeout_range(&exp, delta, HRTIMER_MODE_ABS))
-			break;
-	}
-}
-EXPORT_SYMBOL(usleep_range_state);