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authorJiri Kosina <[email protected]>2021-03-30 09:17:09 +0200
committerJiri Kosina <[email protected]>2021-03-30 09:17:09 +0200
commita6ad93e37e76ec43c9cee6a91dd783fb854c2ff1 (patch)
treed091c71637d37d0fb0255af766a9287de6a4611a /kernel/trace/ring_buffer.c
parent69aea9d2843669387d100e353b5113d1adc9502f (diff)
parentaebf0a11a8c1fb6444d1365db97f90672199a867 (diff)
Merge tag 'platform-drivers-x86-surface-aggregator-v5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 into for-5.13/surface-system-aggregator-intergration
Pull immutable integration branch from Hans de Goede to have a stable base for SSAM (Surface System Aggregator Module) HID transport subsystem merge. ===== Signed tag for the immutable platform-surface-aggregator-registry branch for merging into other sub-systems. Note this is based on v5.12-rc2. =====
Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c21
1 files changed, 18 insertions, 3 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index b9dad3500041..68744c51517e 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2815,6 +2815,17 @@ rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer,
return 0;
/*
+ * It's possible that the event time delta is zero
+ * (has the same time stamp as the previous event)
+ * in which case write_stamp and before_stamp could
+ * be the same. In such a case, force before_stamp
+ * to be different than write_stamp. It doesn't
+ * matter what it is, as long as its different.
+ */
+ if (!delta)
+ rb_time_set(&cpu_buffer->before_stamp, 0);
+
+ /*
* If an event were to come in now, it would see that the
* write_stamp and the before_stamp are different, and assume
* that this event just added itself before updating
@@ -3307,9 +3318,13 @@ static void check_buffer(struct ring_buffer_per_cpu *cpu_buffer,
goto out;
}
atomic_inc(&cpu_buffer->record_disabled);
- pr_warn("[CPU: %d]TIME DOES NOT MATCH expected:%lld actual:%lld delta:%lld after:%lld\n",
- cpu_buffer->cpu,
- ts + info->delta, info->ts, info->delta, info->after);
+ /* There's some cases in boot up that this can happen */
+ WARN_ON_ONCE(system_state != SYSTEM_BOOTING);
+ pr_warn("[CPU: %d]TIME DOES NOT MATCH expected:%lld actual:%lld delta:%lld before:%lld after:%lld%s\n",
+ cpu_buffer->cpu,
+ ts + info->delta, info->ts, info->delta,
+ info->before, info->after,
+ full ? " (full)" : "");
dump_buffer_page(bpage, info, tail);
atomic_dec(&ts_dump);
/* Do not re-enable checking */