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-rw-r--r--kernel/trace/Kconfig2
-rw-r--r--kernel/trace/ring_buffer.c21
-rw-r--r--kernel/trace/trace.c6
-rw-r--r--kernel/trace/trace.h1
-rw-r--r--kernel/trace/trace_events_synth.c4
5 files changed, 28 insertions, 6 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 9c266b93cbc0..7fa82778c3e6 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -694,7 +694,7 @@ config TRACEPOINT_BENCHMARK
help
This option creates the tracepoint "benchmark:benchmark_event".
When the tracepoint is enabled, it kicks off a kernel thread that
- goes into an infinite loop (calling cond_sched() to let other tasks
+ goes into an infinite loop (calling cond_resched() to let other tasks
run), and calls the tracepoint. Each iteration will record the time
it took to write to the tracepoint and the next iteration that
data will be passed to the tracepoint itself. That is, the tracepoint
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 */
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e295c413580e..eccb4e1187cc 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1929,6 +1929,12 @@ static int run_tracer_selftest(struct tracer *type)
if (!selftests_can_run)
return save_selftest(type);
+ if (!tracing_is_on()) {
+ pr_warn("Selftest for tracer %s skipped due to tracing disabled\n",
+ type->name);
+ return 0;
+ }
+
/*
* Run a selftest on this tracer.
* Here we reset the trace buffer, and set the current
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index dec13ff66077..a6446c03cfbc 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -605,7 +605,6 @@ void trace_graph_function(struct trace_array *tr,
void trace_latency_header(struct seq_file *m);
void trace_default_header(struct seq_file *m);
void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
-int trace_empty(struct trace_iterator *iter);
void trace_graph_return(struct ftrace_graph_ret *trace);
int trace_graph_entry(struct ftrace_graph_ent *trace);
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index 2979a96595b4..8d71e6c83f10 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -1225,8 +1225,10 @@ static int __create_synth_event(const char *name, const char *raw_fields)
goto err;
}
- if (!argc)
+ if (!argc) {
+ argv_free(argv);
continue;
+ }
n_fields_this_loop = 0;
consumed = 0;