The following commit has been merged into the timers/core branch of tip:
Commit-ID: 136bccbc2e78d3cd0bd8831e4c5a4509c0ddd945
Gitweb: https://git.kernel.org/tip/136bccbc2e78d3cd0bd8831e4c5a4509c0ddd945
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Wed, 11 Sep 2024 15:17:42 +02:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Wed, 02 Oct 2024 16:53:39 +02:00
ntp: Read reference time only once
The reference time is required twice in ntp_update_offset(). It will not
change in the meantime as the calling code holds the timekeeper lock. Read
it only once and store it into a local variable.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: John Stultz <jstultz@xxxxxxxxxx>
Link: https://lore.kernel.org/all/20240911-devel-anna-maria-b4-timers-ptp-ntp-v1-6-2d52f4e13476@xxxxxxxxxxxxx
---
kernel/time/ntp.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 905b021..0bfd07d 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -283,9 +283,8 @@ static inline s64 ntp_update_offset_fll(s64 offset64, long secs)
static void ntp_update_offset(long offset)
{
- s64 freq_adj;
- s64 offset64;
- long secs;
+ s64 freq_adj, offset64;
+ long secs, real_secs;
if (!(time_status & STA_PLL))
return;
@@ -303,11 +302,12 @@ static void ntp_update_offset(long offset)
* Select how the frequency is to be controlled
* and in which mode (PLL or FLL).
*/
- secs = (long)(__ktime_get_real_seconds() - time_reftime);
+ real_secs = __ktime_get_real_seconds();
+ secs = (long)(real_secs - time_reftime);
if (unlikely(time_status & STA_FREQHOLD))
secs = 0;
- time_reftime = __ktime_get_real_seconds();
+ time_reftime = real_secs;
offset64 = offset;
freq_adj = ntp_update_offset_fll(offset64, secs);
|