Merge tag 'trace-rtla-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull RTLA tracing tool updates from Steven Rostedt:
 "Real Time Analysis Tool updatesfor 5.18:

   - Support for adjusting tracing_threashold

   - Add -a (auto) option to make it easier for users to debug in the field

   - Add -e option to add more events to the trace

   - Add --trigger option to add triggers to events

   - Add --filter option to filter events

   - Add support to save histograms to the file

   - Add --dma-latency to set /dev/cpu_dma_latency

   - Other fixes and cleanups"

* tag 'trace-rtla-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  rtla: Tools main loop cleanup
  rtla/timerlat: Add --dma-latency option
  rtla/osnoise: Fix osnoise hist stop tracing message
  rtla: Check for trace off also in the trace instance
  rtla/trace: Save event histogram output to a file
  rtla: Add --filter support
  rtla/trace: Add trace event filter helpers
  rtla: Add --trigger support
  rtla/trace: Add trace event trigger helpers
  rtla: Add -e/--event support
  rtla/trace: Add trace events helpers
  rtla/timerlat: Add the automatic trace option
  rtla/osnoise: Add the automatic trace option
  rtla/osnoise: Add an option to set the threshold
  rtla/osnoise: Add support to adjust the tracing_thresh

Author: torvalds

Documentation/tools/rtla/common_options.rst

@@ -14,6 +14,25 @@
 
         Save the stopped trace to [*file|osnoise_trace.txt*].
 
+**-e**, **--event** *sys:event*
+
+        Enable an event in the trace (**-t**) session. The argument can be a specific event, e.g., **-e** *sched:sched_switch*, or all events of a system group, e.g., **-e** *sched*. Multiple **-e** are allowed. It is only active when **-t** or **-a** are set.
+
+**--filter** *<filter>*
+
+        Filter the previous **-e** *sys:event* event with *<filter>*. For further information about event filtering see https://www.kernel.org/doc/html/latest/trace/events.html#event-filtering.
+
+**--trigger** *<trigger>*
+        Enable a trace event trigger to the previous **-e** *sys:event*.
+        If the *hist:* trigger is activated, the output histogram will be automatically saved to a file named *system_event_hist.txt*.
+        For example, the command:
+
+        rtla <command> <mode> -t -e osnoise:irq_noise --trigger="hist:key=desc,duration/1000:sort=desc,duration/1000:vals=hitcount"
+
+        Will automatically save the content of the histogram associated to *osnoise:irq_noise* event in *osnoise_irq_noise_hist.txt*.
+
+        For further information about event trigger see https://www.kernel.org/doc/html/latest/trace/events.html#event-triggers.
+
 **-P**, **--priority** *o:prio|r:prio|f:prio|d:runtime:period*
 
         Set scheduling parameters to the osnoise tracer threads, the format to set the priority are:

Documentation/tools/rtla/common_osnoise_options.rst

@@ -1,3 +1,8 @@
+**-a**, **--auto** *us*
+
+        Set the automatic trace mode. This mode sets some commonly used options
+        while debugging the system. It is equivalent to use **-s** *us* **-T 1 -t**.
+
 **-p**, **--period** *us*
 
         Set the *osnoise* tracer period in microseconds.
@@ -15,3 +20,8 @@
 
         Stop the trace if the total sample is higher than the argument in microseconds.
         If **-T** is set, it will also save the trace to the output.
+
+**-T**, **--threshold** *us*
+
+        Specify the minimum delta between two time reads to be considered noise.
+        The default threshold is *5 us*.

Documentation/tools/rtla/common_timerlat_options.rst

@@ -1,3 +1,10 @@
+**-a**, **--auto** *us*
+
+        Set the automatic trace mode. This mode sets some commonly used options
+        while debugging the system. It is equivalent to use **-T** *us* **-s** *us*
+        **-t**. By default, *timerlat* tracer uses FIFO:95 for *timerlat* threads,
+        thus equilavent to **-P** *f:95*.
+
 **-p**, **--period** *us*
 
         Set the *timerlat* tracer period in microseconds.
@@ -14,3 +21,8 @@
 
         Save the stack trace at the *IRQ* if a *Thread* latency is higher than the
         argument in us.
+
+**--dma-latency** *us*
+        Set the /dev/cpu_dma_latency to *us*, aiming to bound exit from idle latencies.
+        *cyclictest* sets this value to *0* by default, use **--dma-latency** *0* to have
+        similar results.

tools/tracing/rtla/src/osnoise.c

@@ -655,6 +655,85 @@ void osnoise_put_print_stack(struct osnoise_context *context)
 	context->orig_print_stack = OSNOISE_OPTION_INIT_VAL;
 }
 
+/*
+ * osnoise_get_tracing_thresh - read and save the original "tracing_thresh"
+ */
+static long long
+osnoise_get_tracing_thresh(struct osnoise_context *context)
+{
+	long long tracing_thresh;
+
+	if (context->tracing_thresh != OSNOISE_OPTION_INIT_VAL)
+		return context->tracing_thresh;
+
+	if (context->orig_tracing_thresh != OSNOISE_OPTION_INIT_VAL)
+		return context->orig_tracing_thresh;
+
+	tracing_thresh = osnoise_read_ll_config("tracing_thresh");
+	if (tracing_thresh < 0)
+		goto out_err;
+
+	context->orig_tracing_thresh = tracing_thresh;
+	return tracing_thresh;
+
+out_err:
+	return OSNOISE_OPTION_INIT_VAL;
+}
+
+/*
+ * osnoise_set_tracing_thresh - set "tracing_thresh"
+ */
+int osnoise_set_tracing_thresh(struct osnoise_context *context, long long tracing_thresh)
+{
+	long long curr_tracing_thresh = osnoise_get_tracing_thresh(context);
+	int retval;
+
+	if (curr_tracing_thresh == OSNOISE_OPTION_INIT_VAL)
+		return -1;
+
+	retval = osnoise_write_ll_config("tracing_thresh", tracing_thresh);
+	if (retval < 0)
+		return -1;
+
+	context->tracing_thresh = tracing_thresh;
+
+	return 0;
+}
+
+/*
+ * osnoise_restore_tracing_thresh - restore the original "tracing_thresh"
+ */
+void osnoise_restore_tracing_thresh(struct osnoise_context *context)
+{
+	int retval;
+
+	if (context->orig_tracing_thresh == OSNOISE_OPTION_INIT_VAL)
+		return;
+
+	if (context->orig_tracing_thresh == context->tracing_thresh)
+		goto out_done;
+
+	retval = osnoise_write_ll_config("tracing_thresh", context->orig_tracing_thresh);
+	if (retval < 0)
+		err_msg("Could not restore original tracing_thresh\n");
+
+out_done:
+	context->tracing_thresh = OSNOISE_OPTION_INIT_VAL;
+}
+
+/*
+ * osnoise_put_tracing_thresh - restore original values and cleanup data
+ */
+void osnoise_put_tracing_thresh(struct osnoise_context *context)
+{
+	osnoise_restore_tracing_thresh(context);
+
+	if (context->orig_tracing_thresh == OSNOISE_OPTION_INIT_VAL)
+		return;
+
+	context->orig_tracing_thresh = OSNOISE_OPTION_INIT_VAL;
+}
+
 /*
  * enable_osnoise - enable osnoise tracer in the trace_instance
  */
@@ -716,6 +795,9 @@ struct osnoise_context *osnoise_context_alloc(void)
 	context->orig_print_stack	= OSNOISE_OPTION_INIT_VAL;
 	context->print_stack		= OSNOISE_OPTION_INIT_VAL;
 
+	context->orig_tracing_thresh	= OSNOISE_OPTION_INIT_VAL;
+	context->tracing_thresh		= OSNOISE_OPTION_INIT_VAL;
+
 	osnoise_get_context(context);
 
 	return context;
@@ -741,6 +823,7 @@ void osnoise_put_context(struct osnoise_context *context)
 	osnoise_put_stop_total_us(context);
 	osnoise_put_timerlat_period_us(context);
 	osnoise_put_print_stack(context);
+	osnoise_put_tracing_thresh(context);
 
 	free(context);
 }

tools/tracing/rtla/src/osnoise.h

@@ -23,6 +23,10 @@ struct osnoise_context {
 	long long		orig_timerlat_period_us;
 	long long		timerlat_period_us;
 
+	/* 0 as init value */
+	long long		orig_tracing_thresh;
+	long long		tracing_thresh;
+
 	/* -1 as init value because 0 is disabled */
 	long long		orig_stop_us;
 	long long		stop_us;
@@ -67,6 +71,10 @@ int osnoise_set_timerlat_period_us(struct osnoise_context *context,
 				   long long timerlat_period_us);
 void osnoise_restore_timerlat_period_us(struct osnoise_context *context);
 
+int osnoise_set_tracing_thresh(struct osnoise_context *context,
+			       long long tracing_thresh);
+void osnoise_restore_tracing_thresh(struct osnoise_context *context);
+
 void osnoise_restore_print_stack(struct osnoise_context *context);
 int osnoise_set_print_stack(struct osnoise_context *context,
 			    long long print_stack);