[tip: timers/core] timekeeping: Convert jiffies_seq to seqcount_raw_spinlock_t

[tip-bot2 for Davidlohr Bueso]

The following commit has been merged into the timers/core branch of tip:

Commit-ID:     1a2b85f1e2a93a3f84243e654d225e4088735336
Gitweb:        https://git.kernel.org/tip/1a2b85f1e2a93a3f84243e654d225e4088735336
Author:        Davidlohr Bueso <dave@xxxxxxxxxxxx>
AuthorDate:    Wed, 21 Oct 2020 12:07:49 -07:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Mon, 26 Oct 2020 11:04:14 +01:00

timekeeping: Convert jiffies_seq to seqcount_raw_spinlock_t

Use the new api and associate the seqcounter to the jiffies_lock enabling
lockdep support - although for this particular case the write-side locking
and non-preemptibility are quite obvious.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201021190749.19363-1-dave@xxxxxxxxxxxx

---
 kernel/time/jiffies.c     | 3 ++-
 kernel/time/timekeeping.h | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c
index eddcf49..a5cffe2 100644
--- a/kernel/time/jiffies.c
+++ b/kernel/time/jiffies.c
@@ -59,7 +59,8 @@ static struct clocksource clocksource_jiffies = {
 };
 
 __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock);
-__cacheline_aligned_in_smp seqcount_t jiffies_seq;
+__cacheline_aligned_in_smp seqcount_raw_spinlock_t jiffies_seq =
+	SEQCNT_RAW_SPINLOCK_ZERO(jiffies_seq, &jiffies_lock);
 
 #if (BITS_PER_LONG < 64)
 u64 get_jiffies_64(void)
diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
index 099737f..6c2cbd9 100644
--- a/kernel/time/timekeeping.h
+++ b/kernel/time/timekeeping.h
@@ -26,7 +26,7 @@ extern void do_timer(unsigned long ticks);
 extern void update_wall_time(void);
 
 extern raw_spinlock_t jiffies_lock;
-extern seqcount_t jiffies_seq;
+extern seqcount_raw_spinlock_t jiffies_seq;
 
 #define CS_NAME_LEN	32