[PATCH 5.15 017/135] timekeeping: Mark NMI safe time accessors as notrace

Greg Kroah-Hartman
2022-05-10T13:55:54Z

From: Kurt Kanzenbach <kurt@linutronix.de>

commit 2c33d775ef4c25c0e1e1cc0fd5496d02f76bfa20 upstream.

Mark the CLOCK_MONOTONIC fast time accessors as notrace. These functions are
used in tracing to retrieve timestamps, so they should not recurse.

Fixes: 4498e7467e9e ("time: Parametrize all tk_fast_mono users")
Fixes: f09cb9a1808e ("time: Introduce tk_fast_raw")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220426175338.3807ca4f@gandalf.local.home/
Link: https://lore.kernel.org/r/20220428062432.61063-1-kurt@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/time/timekeeping.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -482,7 +482,7 @@ static __always_inline u64 __ktime_get_f
* of the following timestamps. Callers need to be aware of that and
* deal with it.
*/
-u64 ktime_get_mono_fast_ns(void)
+u64 notrace ktime_get_mono_fast_ns(void)
{
return __ktime_get_fast_ns(&tk_fast_mono);
}
@@ -494,7 +494,7 @@ EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns
* Contrary to ktime_get_mono_fast_ns() this is always correct because the
* conversion factor is not affected by NTP/PTP correction.
*/
-u64 ktime_get_raw_fast_ns(void)
+u64 notrace ktime_get_raw_fast_ns(void)
{
return __ktime_get_fast_ns(&tk_fast_raw);
}