Commit 347d24fc authored by Valentin Schneider's avatar Valentin Schneider Committed by Steven Rostedt (Google)
Browse files

tracing/filters: Enable filtering the CPU common field by a cpumask 

The tracing_cpumask lets us specify which CPUs are traced in a buffer
instance, but doesn't let us do this on a per-event basis (unless one
creates an instance per event).

A previous commit added filtering scalar fields by a user-given cpumask,
make this work with the CPU common field as well.

This enables doing things like

$ trace-cmd record -e 'sched_switch' -f 'CPU & CPUS{12-52}' \
		   -e 'sched_wakeup' -f 'target_cpu & CPUS{12-52}'

Link: https://lkml.kernel.org/r/20230707172155.70873-5-vschneid@redhat.com



Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Leonardo Bras <leobras@redhat.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: default avatarValentin Schneider <vschneid@redhat.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 3cbec9d7

kernel/trace/trace_events_filter.c

+14 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ enum filter_pred_fn { 
	FILTER_PRED_FN_PCHAR_USER,

	FILTER_PRED_FN_PCHAR,

	FILTER_PRED_FN_CPU,

	FILTER_PRED_FN_CPU_CPUMASK,

	FILTER_PRED_FN_CPUMASK,

	FILTER_PRED_FN_FUNCTION,

	FILTER_PRED_FN_,
@@ -937,6 +938,14 @@ static int filter_pred_cpu(struct filter_pred *pred, void *event) 
	}

}



/* Filter predicate for current CPU vs user-provided cpumask */

static int filter_pred_cpu_cpumask(struct filter_pred *pred, void *event)

{

	int cpu = raw_smp_processor_id();



	return do_filter_scalar_cpumask(pred->op, cpu, pred->mask);

}



/* Filter predicate for cpumask field vs user-provided cpumask */

static int filter_pred_cpumask(struct filter_pred *pred, void *event)

{
@@ -1440,6 +1449,8 @@ static int filter_pred_fn_call(struct filter_pred *pred, void *event) 
		return filter_pred_pchar(pred, event);

	case FILTER_PRED_FN_CPU:

		return filter_pred_cpu(pred, event);

	case FILTER_PRED_FN_CPU_CPUMASK:

		return filter_pred_cpu_cpumask(pred, event);

	case FILTER_PRED_FN_CPUMASK:

		return filter_pred_cpumask(pred, event);

	case FILTER_PRED_FN_FUNCTION:
@@ -1659,6 +1670,7 @@ static int parse_pred(const char *str, void *data, 


		switch (field->filter_type) {

		case FILTER_CPUMASK:

		case FILTER_CPU:

		case FILTER_OTHER:

			break;

		default:
@@ -1714,6 +1726,8 @@ static int parse_pred(const char *str, void *data, 
		i++;

		if (field->filter_type == FILTER_CPUMASK) {

			pred->fn_num = FILTER_PRED_FN_CPUMASK;

		} else if (field->filter_type == FILTER_CPU) {

			pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK;

		} else {

			switch (field->size) {

			case 8: