The following commit has been merged into the locking/urgent branch of tip:
Commit-ID: a7ef9b28aa8d72a1656fa6f0a01bbd1493886317 Gitweb: https://git.kernel.org/tip/a7ef9b28aa8d72a1656fa6f0a01bbd1493886317 Author: Chris Wilson <ch...@chris-wilson.co.uk> AuthorDate: Sat, 25 Jul 2020 19:51:10 +01:00 Committer: Ingo Molnar <mi...@kernel.org> CommitterDate: Sat, 25 Jul 2020 21:47:42 +02:00 locking/lockdep: Fix overflow in presentation of average lock-time Though the number of lock-acquisitions is tracked as unsigned long, this is passed as the divisor to div_s64() which interprets it as a s32, giving nonsense values with more than 2 billion acquisitons. E.g. acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg ------------------------------------------------------------------------- 2350439395 0.07 353.38 649647067.36 0.-32 Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Signed-off-by: Ingo Molnar <mi...@kernel.org> Cc: Peter Zijlstra <pet...@infradead.org> Link: https://lore.kernel.org/r/20200725185110.11588-1-ch...@chris-wilson.co.uk --- kernel/locking/lockdep_proc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index 5525cd3..02ef87f 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -423,7 +423,7 @@ static void seq_lock_time(struct seq_file *m, struct lock_time *lt) seq_time(m, lt->min); seq_time(m, lt->max); seq_time(m, lt->total); - seq_time(m, lt->nr ? div_s64(lt->total, lt->nr) : 0); + seq_time(m, lt->nr ? div64_u64(lt->total, lt->nr) : 0); } static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
