[PATCH 2/8] rtla/auto-analysis: Replace \t with spaces

From: Daniel Bristot de Oliveira
Date: Wed Apr 24 2024 - 10:38:00 EST


When copying timerlat auto-analysis from a terminal to some web pages or
chats, the \t are being replaced with a single ' ' or ' ', breaking
the output.

For example:
## CPU 3 hit stop tracing, analyzing it ##
IRQ handler delay: 1.30 us (0.11 %)
IRQ latency: 1.90 us
Timerlat IRQ duration: 3.00 us (0.24 %)
Blocking thread: 1223.16 us (99.00 %)
insync:4048 1223.16 us
IRQ interference 4.93 us (0.40 %)
local_timer:236 4.93 us
------------------------------------------------------------------------
Thread latency: 1235.47 us (100%)

Replace \t with spaces to avoid this problem.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 27e348b221f6 ("rtla/timerlat: Add auto-analysis core")
Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
---
tools/tracing/rtla/src/timerlat_aa.c | 109 ++++++++++++++++-----------
1 file changed, 63 insertions(+), 46 deletions(-)

diff --git a/tools/tracing/rtla/src/timerlat_aa.c b/tools/tracing/rtla/src/timerlat_aa.c
index 7093fd5333be..7bd80ee2a5b4 100644
--- a/tools/tracing/rtla/src/timerlat_aa.c
+++ b/tools/tracing/rtla/src/timerlat_aa.c
@@ -16,6 +16,9 @@ enum timelat_state {
TIMERLAT_WAITING_THREAD,
};

+/* Used to fill spaces in the output */
+static const char *spaces = " ";
+
#define MAX_COMM 24

/*
@@ -274,14 +277,17 @@ static int timerlat_aa_nmi_handler(struct trace_seq *s, struct tep_record *recor
taa_data->prev_irq_timstamp = start;

trace_seq_reset(taa_data->prev_irqs_seq);
- trace_seq_printf(taa_data->prev_irqs_seq, "\t%24s \t\t\t%9.2f us\n",
- "nmi", ns_to_usf(duration));
+ trace_seq_printf(taa_data->prev_irqs_seq, " %24s %.*s %9.2f us\n",
+ "nmi",
+ 24, spaces,
+ ns_to_usf(duration));
return 0;
}

taa_data->thread_nmi_sum += duration;
- trace_seq_printf(taa_data->nmi_seq, " %24s \t\t\t%9.2f us\n",
- "nmi", ns_to_usf(duration));
+ trace_seq_printf(taa_data->nmi_seq, " %24s %.*s %9.2f us\n",
+ "nmi",
+ 24, spaces, ns_to_usf(duration));

return 0;
}
@@ -323,8 +329,10 @@ static int timerlat_aa_irq_handler(struct trace_seq *s, struct tep_record *recor
taa_data->prev_irq_timstamp = start;

trace_seq_reset(taa_data->prev_irqs_seq);
- trace_seq_printf(taa_data->prev_irqs_seq, "\t%24s:%-3llu \t\t%9.2f us\n",
- desc, vector, ns_to_usf(duration));
+ trace_seq_printf(taa_data->prev_irqs_seq, " %24s:%-3llu %.*s %9.2f us\n",
+ desc, vector,
+ 15, spaces,
+ ns_to_usf(duration));
return 0;
}

@@ -372,8 +380,10 @@ static int timerlat_aa_irq_handler(struct trace_seq *s, struct tep_record *recor
* IRQ interference.
*/
taa_data->thread_irq_sum += duration;
- trace_seq_printf(taa_data->irqs_seq, " %24s:%-3llu \t %9.2f us\n",
- desc, vector, ns_to_usf(duration));
+ trace_seq_printf(taa_data->irqs_seq, " %24s:%-3llu %.*s %9.2f us\n",
+ desc, vector,
+ 24, spaces,
+ ns_to_usf(duration));

return 0;
}
@@ -408,8 +418,10 @@ static int timerlat_aa_softirq_handler(struct trace_seq *s, struct tep_record *r

taa_data->thread_softirq_sum += duration;

- trace_seq_printf(taa_data->softirqs_seq, "\t%24s:%-3llu \t %9.2f us\n",
- softirq_name[vector], vector, ns_to_usf(duration));
+ trace_seq_printf(taa_data->softirqs_seq, " %24s:%-3llu %.*s %9.2f us\n",
+ softirq_name[vector], vector,
+ 24, spaces,
+ ns_to_usf(duration));
return 0;
}

@@ -452,8 +464,10 @@ static int timerlat_aa_thread_handler(struct trace_seq *s, struct tep_record *re
} else {
taa_data->thread_thread_sum += duration;

- trace_seq_printf(taa_data->threads_seq, "\t%24s:%-3llu \t\t%9.2f us\n",
- comm, pid, ns_to_usf(duration));
+ trace_seq_printf(taa_data->threads_seq, " %24s:%-12llu %.*s %9.2f us\n",
+ comm, pid,
+ 15, spaces,
+ ns_to_usf(duration));
}

return 0;
@@ -482,7 +496,8 @@ static int timerlat_aa_stack_handler(struct trace_seq *s, struct tep_record *rec
function = tep_find_function(taa_ctx->tool->trace.tep, caller[i]);
if (!function)
break;
- trace_seq_printf(taa_data->stack_seq, "\t\t-> %s\n", function);
+ trace_seq_printf(taa_data->stack_seq, " %.*s -> %s\n",
+ 14, spaces, function);
}
}
return 0;
@@ -568,23 +583,24 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
exp_irq_ts = taa_data->timer_irq_start_time - taa_data->timer_irq_start_delay;
if (exp_irq_ts < taa_data->prev_irq_timstamp + taa_data->prev_irq_duration) {
if (taa_data->prev_irq_timstamp < taa_data->timer_irq_start_time)
- printf(" Previous IRQ interference: \t\t up to %9.2f us\n",
- ns_to_usf(taa_data->prev_irq_duration));
+ printf(" Previous IRQ interference: %.*s up to %9.2f us\n",
+ 16, spaces,
+ ns_to_usf(taa_data->prev_irq_duration));
}

/*
* The delay that the IRQ suffered before starting.
*/
- printf(" IRQ handler delay: %16s %9.2f us (%.2f %%)\n",
- (ns_to_usf(taa_data->timer_exit_from_idle) > 10) ? "(exit from idle)" : "",
- ns_to_usf(taa_data->timer_irq_start_delay),
- ns_to_per(total, taa_data->timer_irq_start_delay));
+ printf(" IRQ handler delay: %.*s %16s %9.2f us (%.2f %%)\n", 16, spaces,
+ (ns_to_usf(taa_data->timer_exit_from_idle) > 10) ? "(exit from idle)" : "",
+ ns_to_usf(taa_data->timer_irq_start_delay),
+ ns_to_per(total, taa_data->timer_irq_start_delay));

/*
* Timerlat IRQ.
*/
- printf(" IRQ latency: \t\t\t\t %9.2f us\n",
- ns_to_usf(taa_data->tlat_irq_latency));
+ printf(" IRQ latency: %.*s %9.2f us\n", 40, spaces,
+ ns_to_usf(taa_data->tlat_irq_latency));

if (irq) {
/*
@@ -595,15 +611,16 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
* so it will be displayed, it is the key.
*/
printf(" Blocking thread:\n");
- printf(" %24s:%-9llu\n",
- taa_data->run_thread_comm, taa_data->run_thread_pid);
+ printf(" %.*s %24s:%-9llu\n", 6, spaces, taa_data->run_thread_comm,
+ taa_data->run_thread_pid);
} else {
/*
* The duration of the IRQ handler that handled the timerlat IRQ.
*/
- printf(" Timerlat IRQ duration: \t\t %9.2f us (%.2f %%)\n",
- ns_to_usf(taa_data->timer_irq_duration),
- ns_to_per(total, taa_data->timer_irq_duration));
+ printf(" Timerlat IRQ duration: %.*s %9.2f us (%.2f %%)\n",
+ 30, spaces,
+ ns_to_usf(taa_data->timer_irq_duration),
+ ns_to_per(total, taa_data->timer_irq_duration));

/*
* The amount of time that the current thread postponed the scheduler.
@@ -611,13 +628,13 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
* Recalling that it is net from NMI/IRQ/Softirq interference, so there
* is no need to compute values here.
*/
- printf(" Blocking thread: \t\t\t %9.2f us (%.2f %%)\n",
- ns_to_usf(taa_data->thread_blocking_duration),
- ns_to_per(total, taa_data->thread_blocking_duration));
+ printf(" Blocking thread: %.*s %9.2f us (%.2f %%)\n", 36, spaces,
+ ns_to_usf(taa_data->thread_blocking_duration),
+ ns_to_per(total, taa_data->thread_blocking_duration));

- printf(" %24s:%-9llu %9.2f us\n",
- taa_data->run_thread_comm, taa_data->run_thread_pid,
- ns_to_usf(taa_data->thread_blocking_duration));
+ printf(" %.*s %24s:%-9llu %.*s %9.2f us\n", 6, spaces,
+ taa_data->run_thread_comm, taa_data->run_thread_pid,
+ 12, spaces, ns_to_usf(taa_data->thread_blocking_duration));
}

/*
@@ -629,9 +646,9 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
* NMIs can happen during the IRQ, so they are always possible.
*/
if (taa_data->thread_nmi_sum)
- printf(" NMI interference \t\t\t %9.2f us (%.2f %%)\n",
- ns_to_usf(taa_data->thread_nmi_sum),
- ns_to_per(total, taa_data->thread_nmi_sum));
+ printf(" NMI interference %.*s %9.2f us (%.2f %%)\n", 36, spaces,
+ ns_to_usf(taa_data->thread_nmi_sum),
+ ns_to_per(total, taa_data->thread_nmi_sum));

/*
* If it is an IRQ latency, the other factors can be skipped.
@@ -643,9 +660,9 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
* Prints the interference caused by IRQs to the thread latency.
*/
if (taa_data->thread_irq_sum) {
- printf(" IRQ interference \t\t\t %9.2f us (%.2f %%)\n",
- ns_to_usf(taa_data->thread_irq_sum),
- ns_to_per(total, taa_data->thread_irq_sum));
+ printf(" IRQ interference %.*s %9.2f us (%.2f %%)\n", 36, spaces,
+ ns_to_usf(taa_data->thread_irq_sum),
+ ns_to_per(total, taa_data->thread_irq_sum));

trace_seq_do_printf(taa_data->irqs_seq);
}
@@ -654,9 +671,9 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
* Prints the interference caused by Softirqs to the thread latency.
*/
if (taa_data->thread_softirq_sum) {
- printf(" Softirq interference \t\t\t %9.2f us (%.2f %%)\n",
- ns_to_usf(taa_data->thread_softirq_sum),
- ns_to_per(total, taa_data->thread_softirq_sum));
+ printf(" Softirq interference %.*s %9.2f us (%.2f %%)\n", 32, spaces,
+ ns_to_usf(taa_data->thread_softirq_sum),
+ ns_to_per(total, taa_data->thread_softirq_sum));

trace_seq_do_printf(taa_data->softirqs_seq);
}
@@ -670,9 +687,9 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
* timer handling latency.
*/
if (taa_data->thread_thread_sum) {
- printf(" Thread interference \t\t\t %9.2f us (%.2f %%)\n",
- ns_to_usf(taa_data->thread_thread_sum),
- ns_to_per(total, taa_data->thread_thread_sum));
+ printf(" Thread interference %.*s %9.2f us (%.2f %%)\n", 33, spaces,
+ ns_to_usf(taa_data->thread_thread_sum),
+ ns_to_per(total, taa_data->thread_thread_sum));

trace_seq_do_printf(taa_data->threads_seq);
}
@@ -682,8 +699,8 @@ static void timerlat_thread_analysis(struct timerlat_aa_data *taa_data, int cpu,
*/
print_total:
printf("------------------------------------------------------------------------\n");
- printf(" %s latency: \t\t\t %9.2f us (100%%)\n", irq ? "IRQ" : "Thread",
- ns_to_usf(total));
+ printf(" %s latency: %.*s %9.2f us (100%%)\n", irq ? " IRQ" : "Thread",
+ 37, spaces, ns_to_usf(total));
}

static int timerlat_auto_analysis_collect_trace(struct timerlat_aa_context *taa_ctx)
--
2.44.0