Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Make kfree_rcu() use kfree_bulk() for added performance

   - RCU updates

   - Callback-overload handling updates

   - Tasks-RCU KCSAN and sparse updates

   - Locking torture test and RCU torture test updates

   - Documentation updates

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits)
  rcu: Make rcu_barrier() account for offline no-CBs CPUs
  rcu: Mark rcu_state.gp_seq to detect concurrent writes
  Documentation/memory-barriers: Fix typos
  doc: Add rcutorture scripting to torture.txt
  doc/RCU/rcu: Use https instead of http if possible
  doc/RCU/rcu: Use absolute paths for non-rst files
  doc/RCU/rcu: Use ':ref:' for links to other docs
  doc/RCU/listRCU: Update example function name
  doc/RCU/listRCU: Fix typos in a example code snippets
  doc/RCU/Design: Remove remaining HTML tags in ReST files
  doc: Add some more RCU list patterns in the kernel
  rcutorture: Set KCSAN Kconfig options to detect more data races
  rcutorture: Manually clean up after rcu_barrier() failure
  rcutorture: Make rcu_torture_barrier_cbs() post from corresponding CPU
  rcuperf: Measure memory footprint during kfree_rcu() test
  rcutorture: Annotation lockless accesses to rcu_torture_current
  rcutorture: Add READ_ONCE() to rcu_torture_count and rcu_torture_batch
  rcutorture: Fix stray access to rcu_fwd_cb_nodelay
  rcutorture: Fix rcu_torture_one_read()/rcu_torture_writer() data race
  rcutorture: Make kvm-find-errors.sh abort on bad directory
  ...

1 files changed, 4 insertions, 3 deletions

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 4820823515e9..568564ae3597 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -944,6 +944,7 @@ static struct timer_base *lock_timer_base(struct timer_list *timer,
 
 #define MOD_TIMER_PENDING_ONLY		0x01
 #define MOD_TIMER_REDUCE		0x02
+#define MOD_TIMER_NOTPENDING		0x04
 
 static inline int
 __mod_timer(struct timer_list *timer, unsigned long expires, unsigned int options)
@@ -960,7 +961,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, unsigned int option
 	 * the timer is re-modified to have the same timeout or ends up in the
 	 * same array bucket then just return:
 	 */
-	if (timer_pending(timer)) {
+	if (!(options & MOD_TIMER_NOTPENDING) && timer_pending(timer)) {
 		/*
 		 * The downside of this optimization is that it can result in
 		 * larger granularity than you would get from adding a new
@@ -1133,7 +1134,7 @@ EXPORT_SYMBOL(timer_reduce);
 void add_timer(struct timer_list *timer)
 {
 	BUG_ON(timer_pending(timer));
-	mod_timer(timer, timer->expires);
+	__mod_timer(timer, timer->expires, MOD_TIMER_NOTPENDING);
 }
 EXPORT_SYMBOL(add_timer);
 
@@ -1891,7 +1892,7 @@ signed long __sched schedule_timeout(signed long timeout)
 
 	timer.task = current;
 	timer_setup_on_stack(&timer.timer, process_timeout, 0);
-	__mod_timer(&timer.timer, expire, 0);
+	__mod_timer(&timer.timer, expire, MOD_TIMER_NOTPENDING);
 	schedule();
 	del_singleshot_timer_sync(&timer.timer);