The following commit has been merged into the sched/core branch of tip:
Commit-ID: ea19506013ad13685573e4674fbeddb790e27906
Gitweb: https://git.kernel.org/tip/ea19506013ad13685573e4674fbeddb790e27906
Author: Yiyang Chen <cyyzero16@gmail.com>
AuthorDate: Fri, 15 May 2026 00:05:05 +08:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Tue, 19 May 2026 12:17:35 +02:00
sched/clock: Provide !HAVE_UNSTABLE_SCHED_CLOCK stub for sched_clock_stable()
When CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is disabled, sched_clock() is
already assumed to provide stable semantics, but the public header
doesn't provide a sched_clock_stable() stub for that case.
Add a header stub that always returns true and clean up the duplicate
local stub in ring_buffer.c, so callers can use sched_clock_stable()
unconditionally.
Signed-off-by: Yiyang Chen <cyyzero16@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Link: https://patch.msgid.link/56e45338858946cd9581b75c8bd45dd37dba52c5.1778773587.git.cyyzero16@gmail.com
---
include/linux/sched/clock.h | 5 +++++
kernel/trace/ring_buffer.c | 7 -------
2 files changed, 5 insertions(+), 7 deletions(-)
diff --git a/include/linux/sched/clock.h b/include/linux/sched/clock.h
index 196f0ca..39f0a7f 100644
--- a/include/linux/sched/clock.h
+++ b/include/linux/sched/clock.h
@@ -33,6 +33,11 @@ extern u64 sched_clock_cpu(int cpu);
extern void sched_clock_init(void);
#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+static inline int sched_clock_stable(void)
+{
+ return 1;
+}
+
static inline void sched_clock_tick(void)
{
}
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 5326924..02691c3 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -3769,13 +3769,6 @@ rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
return skip_time_extend(event);
}
-#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
-static inline bool sched_clock_stable(void)
-{
- return true;
-}
-#endif
-
static void
rb_check_timestamp(struct ring_buffer_per_cpu *cpu_buffer,
struct rb_event_info *info)