diff options
| author | Jeff Layton <jlayton@kernel.org> | 2024-10-02 17:27:17 -0400 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2024-10-10 10:20:46 +0200 |
| commit | 2a15385742c689a271345dcbb4c28b9c568bc7ce (patch) | |
| tree | ae5946a9f20a5508c8c77a74b574f399d87e1b19 /kernel/time/timekeeping_debug.c | |
| parent | ee3283c608dfa21251b0821d7bb198c7ae3189f6 (diff) | |
timekeeping: Add percpu counter for tracking floor swap events
The mgtime_floor value is a global variable for tracking the latest
fine-grained timestamp handed out. Because it's a global, track the
number of times that a new floor value is assigned.
Add a new percpu counter to the timekeeping code to track the number of
floor swap events that have occurred. A later patch will add a debugfs
file to display this counter alongside other stats involving multigrain
timestamps.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # documentation bits
Link: https://lore.kernel.org/all/20241002-mgtime-v10-2-d1c4717f5284@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'kernel/time/timekeeping_debug.c')
| -rw-r--r-- | kernel/time/timekeeping_debug.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/kernel/time/timekeeping_debug.c b/kernel/time/timekeeping_debug.c index b73e8850e58d..badeb222eab9 100644 --- a/kernel/time/timekeeping_debug.c +++ b/kernel/time/timekeeping_debug.c @@ -17,6 +17,9 @@ #define NUM_BINS 32 +/* Incremented every time mg_floor is updated */ +DEFINE_PER_CPU(unsigned long, timekeeping_mg_floor_swaps); + static unsigned int sleep_time_bin[NUM_BINS] = {0}; static int tk_debug_sleep_time_show(struct seq_file *s, void *data) @@ -53,3 +56,13 @@ void tk_debug_account_sleep_time(const struct timespec64 *t) (s64)t->tv_sec, t->tv_nsec / NSEC_PER_MSEC); } +unsigned long timekeeping_get_mg_floor_swaps(void) +{ + unsigned long sum = 0; + int cpu; + + for_each_possible_cpu(cpu) + sum += data_race(per_cpu(timekeeping_mg_floor_swaps, cpu)); + + return sum; +} |