[tip:timers/urgent] timers: Invoke timer_start_debug() where it makes sense

From: tip-bot for Thomas Gleixner
Date: Fri Dec 29 2017 - 17:50:35 EST


Commit-ID: fd45bb77ad682be728d1002431d77b8c73342836
Gitweb: https://git.kernel.org/tip/fd45bb77ad682be728d1002431d77b8c73342836
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Fri, 22 Dec 2017 15:51:14 +0100
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Fri, 29 Dec 2017 23:13:10 +0100

timers: Invoke timer_start_debug() where it makes sense

The timer start debug function is called before the proper timer base is
set. As a consequence the trace data contains the stale CPU and flags
values.

Call the debug function after setting the new base and flags.

Fixes: 500462a9de65 ("timers: Switch to a non-cascading wheel")
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Sebastian Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: rt@xxxxxxxxxxxxx
Cc: Paul McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20171222145337.792907137@xxxxxxxxxxxxx

---
kernel/time/timer.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 6be576e..89a9e1b 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1007,8 +1007,6 @@ __mod_timer(struct timer_list *timer, unsigned long expires, unsigned int option
if (!ret && (options & MOD_TIMER_PENDING_ONLY))
goto out_unlock;

- debug_activate(timer, expires);
-
new_base = get_target_base(base, timer->flags);

if (base != new_base) {
@@ -1032,6 +1030,8 @@ __mod_timer(struct timer_list *timer, unsigned long expires, unsigned int option
}
}

+ debug_activate(timer, expires);
+
timer->expires = expires;
/*
* If 'idx' was calculated above and the base time did not advance