@@ -321,6 +321,57 @@ static struct osnoise_data {
#endif
};
+#ifdef CONFIG_TIMERLAT_TRACER
+static inline bool timerlat_enabled(void)
+{
+ return osnoise_data.timerlat_tracer;
+}
+
+static inline int timerlat_softirq_exit(struct osnoise_variables *osn_var)
+{
+ struct timerlat_variables *tlat_var = this_cpu_tmr_var();
+ /*
+ * If the timerlat is enabled, but the irq handler did
+ * not run yet enabling timerlat_tracer, do not trace.
+ */
+ if (!tlat_var->tracing_thread) {
+ osn_var->softirq.arrival_time = 0;
+ osn_var->softirq.delta_start = 0;
+ return 0;
+ }
+ return 1;
+}
+
+static inline int timerlat_thread_exit(struct osnoise_variables *osn_var)
+{
+ struct timerlat_variables *tlat_var = this_cpu_tmr_var();
+ /*
+ * If the timerlat is enabled, but the irq handler did
+ * not run yet enabling timerlat_tracer, do not trace.
+ */
+ if (!tlat_var->tracing_thread) {
+ osn_var->thread.delta_start = 0;
+ osn_var->thread.arrival_time = 0;
+ return 0;
+ }
+ return 1;
+}
+#else /* CONFIG_TIMERLAT_TRACER */
+static inline bool timerlat_enabled(void)
+{
+ return false;
+}
+
+static inline int timerlat_softirq_exit(struct osnoise_variables *osn_var)
+{
+ return 1;
+}
+static inline int timerlat_thread_exit(struct osnoise_variables *osn_var)
+{
+ return 1;
+}
+#endif
+
#ifdef CONFIG_PREEMPT_RT
/*
* Print the osnoise header info.
@@ -977,21 +1028,9 @@ static void trace_softirq_exit_callback(void *data, unsigned int vec_nr)
if (!osn_var->sampling)
return;
-#ifdef CONFIG_TIMERLAT_TRACER
- /*
- * If the timerlat is enabled, but the irq handler did
- * not run yet enabling timerlat_tracer, do not trace.
- */
- if (unlikely(osnoise_data.timerlat_tracer)) {
- struct timerlat_variables *tlat_var;
- tlat_var = this_cpu_tmr_var();
- if (!tlat_var->tracing_thread) {
- osn_var->softirq.arrival_time = 0;
- osn_var->softirq.delta_start = 0;
+ if (unlikely(timerlat_enabled()))
+ if (!timerlat_softirq_exit(osn_var))
return;
- }
- }
-#endif
duration = get_int_safe_duration(osn_var, &osn_var->softirq.delta_start);
trace_softirq_noise(vec_nr, osn_var->softirq.arrival_time, duration);
@@ -1085,17 +1124,9 @@ thread_exit(struct osnoise_variables *osn_var, struct task_struct *t)
if (!osn_var->sampling)
return;
-#ifdef CONFIG_TIMERLAT_TRACER
- if (osnoise_data.timerlat_tracer) {
- struct timerlat_variables *tlat_var;
- tlat_var = this_cpu_tmr_var();
- if (!tlat_var->tracing_thread) {
- osn_var->thread.delta_start = 0;
- osn_var->thread.arrival_time = 0;
+ if (unlikely(timerlat_enabled()))
+ if (!timerlat_thread_exit(osn_var))
return;
- }
- }
-#endif
duration = get_int_safe_duration(osn_var, &osn_var->thread.delta_start);
@@ -1599,6 +1630,11 @@ static int timerlat_main(void *data)
hrtimer_cancel(&tlat->timer);
return 0;
}
+#else /* CONFIG_TIMERLAT_TRACER */
+static int timerlat_main(void *data)
+{
+ return 0;
+}
#endif /* CONFIG_TIMERLAT_TRACER */
/*
@@ -1641,16 +1677,13 @@ static int start_kthread(unsigned int cpu)
void *main = osnoise_main;
char comm[24];
-#ifdef CONFIG_TIMERLAT_TRACER
- if (osnoise_data.timerlat_tracer) {
+ if (timerlat_enabled()) {
snprintf(comm, 24, "timerlat/%d", cpu);
main = timerlat_main;
} else {
snprintf(comm, 24, "osnoise/%d", cpu);
}
-#else
- snprintf(comm, 24, "osnoise/%d", cpu);
-#endif
+
kthread = kthread_create_on_cpu(main, NULL, cpu, comm);
if (IS_ERR(kthread)) {
@@ -1944,6 +1977,35 @@ static const struct file_operations cpus_fops = {
.llseek = generic_file_llseek,
};
+#ifdef CONFIG_TIMERLAT_TRACER
+/*
+ * init_timerlat_tracefs - A function to initialize the timerlat interface files
+ */
+static int init_timerlat_tracefs(struct dentry *top_dir)
+{
+ struct dentry *tmp;
+
+#ifdef CONFIG_STACKTRACE
+ tmp = tracefs_create_file("print_stack", 0640, top_dir,
+ &osnoise_print_stack, &trace_min_max_fops);
+ if (!tmp)
+ return -ENOMEM;
+#endif
+
+ tmp = tracefs_create_file("timerlat_period_us", 0640, top_dir,
+ &timerlat_period, &trace_min_max_fops);
+ if (!tmp)
+ return -ENOMEM;
+
+ return 0;
+}
+#else /* CONFIG_TIMERLAT_TRACER */
+static int init_timerlat_tracefs(struct dentry *top_dir)
+{
+ return 0;
+}
+#endif /* CONFIG_TIMERLAT_TRACER */
+
/*
* init_tracefs - A function to initialize the tracefs interface files
*
@@ -1988,19 +2050,10 @@ static int init_tracefs(void)
tmp = trace_create_file("cpus", 0644, top_dir, NULL, &cpus_fops);
if (!tmp)
goto err;
-#ifdef CONFIG_TIMERLAT_TRACER
-#ifdef CONFIG_STACKTRACE
- tmp = tracefs_create_file("print_stack", 0640, top_dir,
- &osnoise_print_stack, &trace_min_max_fops);
- if (!tmp)
- goto err;
-#endif
- tmp = tracefs_create_file("timerlat_period_us", 0640, top_dir,
- &timerlat_period, &trace_min_max_fops);
- if (!tmp)
+ ret = init_timerlat_tracefs(top_dir);
+ if (ret)
goto err;
-#endif
return 0;
@@ -2206,6 +2259,16 @@ static struct tracer timerlat_tracer __read_mostly = {
.print_header = print_timerlat_headers,
.allow_instances = true,
};
+
+__init static int init_timerlat_tracer(void)
+{
+ return register_tracer(&timerlat_tracer);
+}
+#else /* CONFIG_TIMERLAT_TRACER */
+__init static int init_timerlat_tracer(void)
+{
+ return 0;
+}
#endif /* CONFIG_TIMERLAT_TRACER */
__init static int init_osnoise_tracer(void)
@@ -2222,13 +2285,12 @@ __init static int init_osnoise_tracer(void)
return ret;
}
-#ifdef CONFIG_TIMERLAT_TRACER
- ret = register_tracer(&timerlat_tracer);
+ ret = init_timerlat_tracer();
if (ret) {
- pr_err(BANNER "Error registering timerlat\n");
+ pr_err(BANNER "Error registering timerlat!\n");
return ret;
}
-#endif
+
osnoise_init_hotplug_support();
INIT_LIST_HEAD_RCU(&osnoise_instances);
Remove CONFIG_TIMERLAT_TRACER from inside functions, avoiding compilation problems in the future. Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-rt-users@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> --- kernel/trace/trace_osnoise.c | 150 +++++++++++++++++++++++++---------- 1 file changed, 106 insertions(+), 44 deletions(-)