tools/perf/scripts/perl/wakeup-latency.pl

Source file repositories/reference/linux-study-clean/tools/perf/scripts/perl/wakeup-latency.pl

File Facts

System
Linux kernel
Corpus path
tools/perf/scripts/perl/wakeup-latency.pl
Extension
.pl
Size
2821 bytes
Lines
108
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: tools
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

if ($wakeup_ts) {
	my $switch_ts = nsecs($common_secs, $common_nsecs);
	my $wakeup_latency = $switch_ts - $wakeup_ts;
	if ($wakeup_latency > $max_wakeup_latency) {
	    $max_wakeup_latency = $wakeup_latency;
	}
	if ($wakeup_latency < $min_wakeup_latency) {
	    $min_wakeup_latency = $wakeup_latency;
	}
	$total_wakeup_latency += $wakeup_latency;
	$total_wakeups++;
    }
    $last_wakeup{$common_cpu}{ts} = 0;
}

sub sched::sched_wakeup
{
    my ($event_name, $context, $common_cpu, $common_secs, $common_nsecs,
	$common_pid, $common_comm, $common_callchain,
	$comm, $pid, $prio, $success, $target_cpu) = @_;

    $last_wakeup{$target_cpu}{ts} = nsecs($common_secs, $common_nsecs);
}

sub trace_begin
{
    $min_wakeup_latency = 1000000000;
    $max_wakeup_latency = 0;
}

sub trace_end
{
    printf("wakeup_latency stats:\n\n");
    print "total_wakeups: $total_wakeups\n";
    if ($total_wakeups) {
	printf("avg_wakeup_latency (ns): %u\n",
	       avg($total_wakeup_latency, $total_wakeups));
    } else {
	printf("avg_wakeup_latency (ns): N/A\n");
    }
    printf("min_wakeup_latency (ns): %u\n", $min_wakeup_latency);
    printf("max_wakeup_latency (ns): %u\n", $max_wakeup_latency);

    print_unhandled();
}

my %unhandled;

sub print_unhandled
{
    if ((scalar keys %unhandled) == 0) {
	return;
    }

    print "\nunhandled events:\n\n";

    printf("%-40s  %10s\n", "event", "count");
    printf("%-40s  %10s\n", "----------------------------------------",
	   "-----------");

    foreach my $event_name (keys %unhandled) {
	printf("%-40s  %10d\n", $event_name, $unhandled{$event_name});
    }
}

sub trace_unhandled
{
    my ($event_name, $context, $common_cpu, $common_secs, $common_nsecs,
	$common_pid, $common_comm, $common_callchain) = @_;

Annotation

Implementation Notes