[for-next][PATCH 7/8] rtla: Add hwnoise tool

From: Steven Rostedt
Date: Sat Feb 18 2023 - 15:19:56 EST

From: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>

The hwnoise tool is a special mode for the osnoise top tool.

hwnoise dispatches the osnoise tracer and displays a summary of the noise.
The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE
option set, thus only allowing only hardware-related noise, resulting in
a simplified output. hwnoise has the same features of osnoise.

An example of the tool's output:

# rtla hwnoise -c 1-11 -T 1 -d 10m -q
Hardware-related Noise
duration: 0 00:10:00 | time is in us
CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI
1 #599 599000000 138 99.99997 3 3 4 74
2 #599 599000000 85 99.99998 3 3 4 75
3 #599 599000000 86 99.99998 4 3 6 75
4 #599 599000000 81 99.99998 4 4 2 75
5 #599 599000000 85 99.99998 2 2 2 75

Link: https://lkml.kernel.org/r/2d6f49a6f3a4f8b51b2c806458b1cff71ad4d014.1675805361.git.bristot@xxxxxxxxxx

Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Clark Williams <williams@xxxxxxxxxx>
Cc: Bagas Sanjaya <bagasdotme@xxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
tools/tracing/rtla/Makefile | 2 +
tools/tracing/rtla/src/osnoise.c | 117 +++++++++++++++++++++++++++
tools/tracing/rtla/src/osnoise.h | 7 ++
tools/tracing/rtla/src/osnoise_top.c | 84 +++++++++++++++----
tools/tracing/rtla/src/rtla.c | 4 +
5 files changed, 198 insertions(+), 16 deletions(-)

diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile
index 22e28b76f800..2456a399eb9a 100644
--- a/tools/tracing/rtla/Makefile
+++ b/tools/tracing/rtla/Makefile
@@ -119,6 +119,8 @@ install: doc_install
$(STRIP) $(DESTDIR)$(BINDIR)/rtla
@test ! -f $(DESTDIR)$(BINDIR)/osnoise || rm $(DESTDIR)$(BINDIR)/osnoise
ln -s rtla $(DESTDIR)$(BINDIR)/osnoise
+ @test ! -f $(DESTDIR)$(BINDIR)/hwnoise || rm $(DESTDIR)$(BINDIR)/hwnoise
+ ln -s rtla $(DESTDIR)$(BINDIR)/hwnoise
@test ! -f $(DESTDIR)$(BINDIR)/timerlat || rm $(DESTDIR)$(BINDIR)/timerlat
ln -s rtla $(DESTDIR)$(BINDIR)/timerlat

diff --git a/tools/tracing/rtla/src/osnoise.c b/tools/tracing/rtla/src/osnoise.c
index 4dee343909b1..3ca7a3853943 100644
--- a/tools/tracing/rtla/src/osnoise.c
+++ b/tools/tracing/rtla/src/osnoise.c
@@ -734,6 +734,113 @@ void osnoise_put_tracing_thresh(struct osnoise_context *context)
context->orig_tracing_thresh = OSNOISE_OPTION_INIT_VAL;
}

+static int osnoise_options_get_option(char *option)
+{
+ char *options = tracefs_instance_file_read(NULL, "osnoise/options", NULL);
+ char no_option[128];
+ int retval = 0;
+ char *opt;
+
+ if (!options)
+ return OSNOISE_OPTION_INIT_VAL;
+
+ /*
+ * Check first if the option is disabled.
+ */
+ snprintf(no_option, sizeof(no_option), "NO_%s", option);
+
+ opt = strstr(options, no_option);
+ if (opt)
+ goto out_free;
+
+ /*
+ * Now that it is not disabled, if the string is there, it is
+ * enabled. If the string is not there, the option does not exist.
+ */
+ opt = strstr(options, option);
+ if (opt)
+ retval = 1;
+ else
+ retval = OSNOISE_OPTION_INIT_VAL;
+
+out_free:
+ free(options);
+ return retval;
+}
+
+static int osnoise_options_set_option(char *option, bool onoff)
+{
+ char no_option[128];
+
+ if (onoff)
+ return tracefs_instance_file_write(NULL, "osnoise/options", option);
+
+ snprintf(no_option, sizeof(no_option), "NO_%s", option);
+
+ return tracefs_instance_file_write(NULL, "osnoise/options", no_option);
+}
+
+static int osnoise_get_irq_disable(struct osnoise_context *context)
+{
+ if (context->opt_irq_disable != OSNOISE_OPTION_INIT_VAL)
+ return context->opt_irq_disable;
+
+ if (context->orig_opt_irq_disable != OSNOISE_OPTION_INIT_VAL)
+ return context->orig_opt_irq_disable;
+
+ context->orig_opt_irq_disable = osnoise_options_get_option("OSNOISE_IRQ_DISABLE");
+
+ return context->orig_opt_irq_disable;
+}
+
+int osnoise_set_irq_disable(struct osnoise_context *context, bool onoff)
+{
+ int opt_irq_disable = osnoise_get_irq_disable(context);
+ int retval;
+
+ if (opt_irq_disable == OSNOISE_OPTION_INIT_VAL)
+ return -1;
+
+ if (opt_irq_disable == onoff)
+ return 0;
+
+ retval = osnoise_options_set_option("OSNOISE_IRQ_DISABLE", onoff);
+ if (retval < 0)
+ return -1;
+
+ context->opt_irq_disable = onoff;
+
+ return 0;
+}
+
+static void osnoise_restore_irq_disable(struct osnoise_context *context)
+{
+ int retval;
+
+ if (context->orig_opt_irq_disable == OSNOISE_OPTION_INIT_VAL)
+ return;
+
+ if (context->orig_opt_irq_disable == context->opt_irq_disable)
+ goto out_done;
+
+ retval = osnoise_options_set_option("OSNOISE_IRQ_DISABLE", context->orig_opt_irq_disable);
+ if (retval < 0)
+ err_msg("Could not restore original OSNOISE_IRQ_DISABLE option\n");
+
+out_done:
+ context->orig_opt_irq_disable = OSNOISE_OPTION_INIT_VAL;
+}
+
+static void osnoise_put_irq_disable(struct osnoise_context *context)
+{
+ osnoise_restore_irq_disable(context);
+
+ if (context->orig_opt_irq_disable == OSNOISE_OPTION_INIT_VAL)
+ return;
+
+ context->orig_opt_irq_disable = OSNOISE_OPTION_INIT_VAL;
+}
+
/*
* enable_osnoise - enable osnoise tracer in the trace_instance
*/
@@ -798,6 +905,9 @@ struct osnoise_context *osnoise_context_alloc(void)
context->orig_tracing_thresh = OSNOISE_OPTION_INIT_VAL;
context->tracing_thresh = OSNOISE_OPTION_INIT_VAL;

+ context->orig_opt_irq_disable = OSNOISE_OPTION_INIT_VAL;
+ context->opt_irq_disable = OSNOISE_OPTION_INIT_VAL;
+
osnoise_get_context(context);

return context;
@@ -824,6 +934,7 @@ void osnoise_put_context(struct osnoise_context *context)
osnoise_put_timerlat_period_us(context);
osnoise_put_print_stack(context);
osnoise_put_tracing_thresh(context);
+ osnoise_put_irq_disable(context);

free(context);
}
@@ -958,3 +1069,9 @@ int osnoise_main(int argc, char *argv[])
osnoise_usage(1);
exit(1);
}
+
+int hwnoise_main(int argc, char *argv[])
+{
+ osnoise_top_main(argc, argv);
+ exit(0);
+}
diff --git a/tools/tracing/rtla/src/osnoise.h b/tools/tracing/rtla/src/osnoise.h
index 04a4384cc544..4dcf22ccd704 100644
--- a/tools/tracing/rtla/src/osnoise.h
+++ b/tools/tracing/rtla/src/osnoise.h
@@ -38,6 +38,10 @@ struct osnoise_context {
/* -1 as init value because 0 is disabled */
long long orig_print_stack;
long long print_stack;
+
+ /* -1 as init value because 0 is off */
+ int orig_opt_irq_disable;
+ int opt_irq_disable;
};

/*
@@ -79,6 +83,8 @@ void osnoise_restore_print_stack(struct osnoise_context *context);
int osnoise_set_print_stack(struct osnoise_context *context,
long long print_stack);

+int osnoise_set_irq_disable(struct osnoise_context *context, bool onoff);
+
/*
* osnoise_tool - osnoise based tool definition.
*/
@@ -97,3 +103,4 @@ struct osnoise_tool *osnoise_init_trace_tool(char *tracer);
int osnoise_hist_main(int argc, char *argv[]);
int osnoise_top_main(int argc, char **argv);
int osnoise_main(int argc, char **argv);
+int hwnoise_main(int argc, char **argv);
diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
index 76479bfb2922..562f2e4b18c5 100644
--- a/tools/tracing/rtla/src/osnoise_top.c
+++ b/tools/tracing/rtla/src/osnoise_top.c
@@ -14,6 +14,11 @@
#include "osnoise.h"
#include "utils.h"

+enum osnoise_mode {
+ MODE_OSNOISE = 0,
+ MODE_HWNOISE
+};
+
/*
* osnoise top parameters
*/
@@ -32,6 +37,7 @@ struct osnoise_top_params {
int set_sched;
struct sched_attr sched_param;
struct trace_events *events;
+ enum osnoise_mode mode;
};

struct osnoise_top_cpu {
@@ -143,15 +149,23 @@ osnoise_top_handler(struct trace_seq *s, struct tep_record *record,
*/
static void osnoise_top_header(struct osnoise_tool *top)
{
+ struct osnoise_top_params *params = top->params;
struct trace_seq *s = top->trace.seq;
char duration[26];

get_duration(top->start_time, duration, sizeof(duration));

trace_seq_printf(s, "\033[2;37;40m");
- trace_seq_printf(s, " Operating System Noise");
- trace_seq_printf(s, " ");
- trace_seq_printf(s, " ");
+ trace_seq_printf(s, " ");
+
+ if (params->mode == MODE_OSNOISE) {
+ trace_seq_printf(s, "Operating System Noise");
+ trace_seq_printf(s, " ");
+ } else if (params->mode == MODE_HWNOISE) {
+ trace_seq_printf(s, "Hardware-related Noise");
+ }
+
+ trace_seq_printf(s, " ");
trace_seq_printf(s, "\033[0;0;0m");
trace_seq_printf(s, "\n");

@@ -162,7 +176,14 @@ static void osnoise_top_header(struct osnoise_tool *top)
trace_seq_printf(s, " Noise ");
trace_seq_printf(s, " %% CPU Aval ");
trace_seq_printf(s, " Max Noise Max Single ");
- trace_seq_printf(s, " HW NMI IRQ Softirq Thread");
+ trace_seq_printf(s, " HW NMI");
+
+ if (params->mode == MODE_HWNOISE)
+ goto eol;
+
+ trace_seq_printf(s, " IRQ Softirq Thread");
+
+eol:
trace_seq_printf(s, "\033[0;0;0m");
trace_seq_printf(s, "\n");
}
@@ -181,6 +202,7 @@ static void clear_terminal(struct trace_seq *seq)
*/
static void osnoise_top_print(struct osnoise_tool *tool, int cpu)
{
+ struct osnoise_top_params *params = tool->params;
struct trace_seq *s = tool->trace.seq;
struct osnoise_top_cpu *cpu_data;
struct osnoise_top_data *data;
@@ -205,6 +227,12 @@ static void osnoise_top_print(struct osnoise_tool *tool, int cpu)

trace_seq_printf(s, "%12llu ", cpu_data->hw_count);
trace_seq_printf(s, "%12llu ", cpu_data->nmi_count);
+
+ if (params->mode == MODE_HWNOISE) {
+ trace_seq_printf(s, "\n");
+ return;
+ }
+
trace_seq_printf(s, "%12llu ", cpu_data->irq_count);
trace_seq_printf(s, "%12llu ", cpu_data->softirq_count);
trace_seq_printf(s, "%12llu\n", cpu_data->thread_count);
@@ -241,12 +269,12 @@ osnoise_print_stats(struct osnoise_top_params *params, struct osnoise_tool *top)
/*
* osnoise_top_usage - prints osnoise top usage message
*/
-void osnoise_top_usage(char *usage)
+static void osnoise_top_usage(struct osnoise_top_params *params, char *usage)
{
int i;

static const char * const msg[] = {
- " usage: rtla osnoise [top] [-h] [-q] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\",
+ " [-h] [-q] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\",
" [-T us] [-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] \\",
" [-c cpu-list] [-P priority]",
"",
@@ -277,9 +305,22 @@ void osnoise_top_usage(char *usage)
if (usage)
fprintf(stderr, "%s\n", usage);

- fprintf(stderr, "rtla osnoise top: a per-cpu summary of the OS noise (version %s)\n",
+ if (params->mode == MODE_OSNOISE) {
+ fprintf(stderr,
+ "rtla osnoise top: a per-cpu summary of the OS noise (version %s)\n",
VERSION);

+ fprintf(stderr, " usage: rtla osnoise [top]");
+ }
+
+ if (params->mode == MODE_HWNOISE) {
+ fprintf(stderr,
+ "rtla hwnoise: a summary of hardware-related noise (version %s)\n",
+ VERSION);
+
+ fprintf(stderr, " usage: rtla hwnoise");
+ }
+
for (i = 0; msg[i]; i++)
fprintf(stderr, "%s\n", msg[i]);
exit(1);
@@ -299,6 +340,9 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
if (!params)
exit(1);

+ if (strcmp(argv[0], "hwnoise") == 0)
+ params->mode = MODE_HWNOISE;
+
while (1) {
static struct option long_options[] = {
{"auto", required_argument, 0, 'a'},
@@ -345,7 +389,7 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
case 'c':
retval = parse_cpu_list(optarg, &params->monitored_cpus);
if (retval)
- osnoise_top_usage("\nInvalid -c cpu list\n");
+ osnoise_top_usage(params, "\nInvalid -c cpu list\n");
params->cpus = optarg;
break;
case 'D':
@@ -354,7 +398,7 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
case 'd':
params->duration = parse_seconds_duration(optarg);
if (!params->duration)
- osnoise_top_usage("Invalid -D duration\n");
+ osnoise_top_usage(params, "Invalid -D duration\n");
break;
case 'e':
tevent = trace_event_alloc(optarg);
@@ -370,17 +414,17 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
break;
case 'h':
case '?':
- osnoise_top_usage(NULL);
+ osnoise_top_usage(params, NULL);
break;
case 'p':
params->period = get_llong_from_str(optarg);
if (params->period > 10000000)
- osnoise_top_usage("Period longer than 10 s\n");
+ osnoise_top_usage(params, "Period longer than 10 s\n");
break;
case 'P':
retval = parse_prio(optarg, &params->sched_param);
if (retval == -1)
- osnoise_top_usage("Invalid -P priority");
+ osnoise_top_usage(params, "Invalid -P priority");
params->set_sched = 1;
break;
case 'q':
@@ -389,7 +433,7 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
case 'r':
params->runtime = get_llong_from_str(optarg);
if (params->runtime < 100)
- osnoise_top_usage("Runtime shorter than 100 us\n");
+ osnoise_top_usage(params, "Runtime shorter than 100 us\n");
break;
case 's':
params->stop_us = get_llong_from_str(optarg);
@@ -415,7 +459,7 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
exit(EXIT_FAILURE);
}
} else {
- osnoise_top_usage("--trigger requires a previous -e\n");
+ osnoise_top_usage(params, "--trigger requires a previous -e\n");
}
break;
case '1': /* filter */
@@ -426,11 +470,11 @@ struct osnoise_top_params *osnoise_top_parse_args(int argc, char **argv)
exit(EXIT_FAILURE);
}
} else {
- osnoise_top_usage("--filter requires a previous -e\n");
+ osnoise_top_usage(params, "--filter requires a previous -e\n");
}
break;
default:
- osnoise_top_usage("Invalid option");
+ osnoise_top_usage(params, "Invalid option");
}
}

@@ -495,6 +539,14 @@ osnoise_top_apply_config(struct osnoise_tool *tool, struct osnoise_top_params *p
}
}

+ if (params->mode == MODE_HWNOISE) {
+ retval = osnoise_set_irq_disable(tool->context, 1);
+ if (retval) {
+ err_msg("Failed to set OSNOISE_IRQ_DISABLE option\n");
+ goto out_err;
+ }
+ }
+
return 0;

out_err:
diff --git a/tools/tracing/rtla/src/rtla.c b/tools/tracing/rtla/src/rtla.c
index 52e8f1825281..7635c70123ab 100644
--- a/tools/tracing/rtla/src/rtla.c
+++ b/tools/tracing/rtla/src/rtla.c
@@ -26,6 +26,7 @@ static void rtla_usage(int err)
"",
" commands:",
" osnoise - gives information about the operating system noise (osnoise)",
+ " hwnoise - gives information about hardware-related noise",
" timerlat - measures the timer irq and thread latency",
"",
NULL,
@@ -47,6 +48,9 @@ int run_command(int argc, char **argv, int start_position)
if (strcmp(argv[start_position], "osnoise") == 0) {
osnoise_main(argc-start_position, &argv[start_position]);
goto ran;
+ } else if (strcmp(argv[start_position], "hwnoise") == 0) {
+ hwnoise_main(argc-start_position, &argv[start_position]);
+ goto ran;
} else if (strcmp(argv[start_position], "timerlat") == 0) {
timerlat_main(argc-start_position, &argv[start_position]);
goto ran;
--
2.39.1