[PATCH v3 0/3] rtla: fix cgroup and trace options parsing

[PATCH v3 0/3] rtla: fix cgroup and trace options parsing

[Ivan Pravdin]

This series fixes 3 issue in rtla timerlat and osnoise parsing.

1. Fix buffer overflow when using --on-threshold option. Currently
   passing `--on-threshold trace` causes rtla timerlat to segfault.
   First patch addresses this issue.

2. Make -C/--cgroup option more user-friendly. Currently rtla timerlat
   and osnoise parses does not allow to specify tracer's threads cgroup
   name as `-C [cgroup]` or `--cgroup [cgroup]`. Second patch fixes this
   by allowing users to specify cgroup in the aforementioned manner.

3. When specifying `-t/--trace` before `-a/--auto`, trace filename is
   override to default <osnoise|timerlat>_trace.txt. For example, when
   running rtla as

       `rtla timerlat top -t custom_file.txt -a 100`

   when the threshold is reached, timerlat_trace.txt file is created
   instead of specified custom_file.txt. Third patch addresses this
   issue.

changes v2 -> v3:
   - Combined common logic into a utility function to parse optional
     argument value
   - Removed change that removed `clear_terminal` 

changes v1 -> v2:
   - Moved removing clear_terminal from `fix -C/--cgroup interface`
     patch to `fix -a overriding -t argument` patch
   - Added clarification why to remove clear_terminal
   - Added `Fixes:` tag to the `fix -C/--cgroup interface` patch

v2: https://lore.kernel.org/all/cover.1755018581.git.ipravdin.official@gmail.com/
v1: https://lore.kernel.org/all/cover.1755014784.git.ipravdin.official@gmail.com/

Ivan Pravdin (3):
  rtla: fix buffer overflow in actions_parse
  rtla: fix -C/--cgroup interface
  rtla: fix -a overriding -t argument

 Documentation/tools/rtla/common_options.rst |  2 +-
 tools/tracing/rtla/src/actions.c            |  2 +-
 tools/tracing/rtla/src/osnoise_hist.c       | 29 +++++++--------------
 tools/tracing/rtla/src/osnoise_top.c        | 29 +++++++--------------
 tools/tracing/rtla/src/timerlat_hist.c      | 29 +++++++--------------
 tools/tracing/rtla/src/timerlat_top.c       | 29 +++++++--------------
 tools/tracing/rtla/src/utils.c              | 26 ++++++++++++++++++
 tools/tracing/rtla/src/utils.h              |  1 +
 8 files changed, 65 insertions(+), 82 deletions(-)

-- 
2.48.1

[PATCH v3 1/3] rtla: fix buffer overflow in actions_parse

[Ivan Pravdin]

Currently, tests 3 and 13-22 in tests/timerlat.t fail with error:

    *** buffer overflow detected ***: terminated
    timeout: the monitored command dumped core

The result of running `sudo make check` is

    tests/timerlat.t (Wstat: 0 Tests: 22 Failed: 11)
      Failed tests:  3, 13-22
    Files=3, Tests=34, 140 wallclock secs ( 0.07 usr  0.01 sys + 27.63 cusr
    27.96 csys = 55.67 CPU)
    Result: FAIL

Fix buffer overflow in actions_parse to avoid this error. After this
change, the tests results are

    tests/hwnoise.t ... ok
    tests/osnoise.t ... ok
    tests/timerlat.t .. ok
    All tests successful.
    Files=3, Tests=34, 186 wallclock secs ( 0.06 usr  0.01 sys + 41.10 cusr
    44.38 csys = 85.55 CPU)
    Result: PASS

Fixes: 6ea082b171e0 ("rtla/timerlat: Add action on threshold feature")
Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com>
Reviewed-by: Tomas Glozar <tglozar@redhat.com>
---
 tools/tracing/rtla/src/actions.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/tracing/rtla/src/actions.c b/tools/tracing/rtla/src/actions.c
index aaf0808125d7..eab51c0c0ce2 100644
--- a/tools/tracing/rtla/src/actions.c
+++ b/tools/tracing/rtla/src/actions.c
@@ -131,7 +131,7 @@ actions_parse(struct actions *self, const char *trigger)
 {
 	enum action_type type = ACTION_NONE;
 	char *token;
-	char trigger_c[strlen(trigger)];
+	char trigger_c[strlen(trigger) + 1];
 
 	/* For ACTION_SIGNAL */
 	int signal = 0, pid = 0;
-- 
2.48.1

Re: [PATCH v3 1/3] rtla: fix buffer overflow in actions_parse

[Tomas Glozar]

Steven,

po 8. 9. 2025 v 4:06 odesílatel Ivan Pravdin
<ipravdin.official@gmail.com> napsal:
>
> Currently, tests 3 and 13-22 in tests/timerlat.t fail with error:
>
>     *** buffer overflow detected ***: terminated
>     timeout: the monitored command dumped core
>
> The result of running `sudo make check` is
>
>     tests/timerlat.t (Wstat: 0 Tests: 22 Failed: 11)
>       Failed tests:  3, 13-22
>     Files=3, Tests=34, 140 wallclock secs ( 0.07 usr  0.01 sys + 27.63 cusr
>     27.96 csys = 55.67 CPU)
>     Result: FAIL
>
> Fix buffer overflow in actions_parse to avoid this error. After this
> change, the tests results are
>
>     tests/hwnoise.t ... ok
>     tests/osnoise.t ... ok
>     tests/timerlat.t .. ok
>     All tests successful.
>     Files=3, Tests=34, 186 wallclock secs ( 0.06 usr  0.01 sys + 41.10 cusr
>     44.38 csys = 85.55 CPU)
>     Result: PASS
>
> Fixes: 6ea082b171e0 ("rtla/timerlat: Add action on threshold feature")
> Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com>
> Reviewed-by: Tomas Glozar <tglozar@redhat.com>
> ---
>  tools/tracing/rtla/src/actions.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Could you take this simple fix? (Might require tweaking the starting
letter "fix" -> "Fix", I don't care that much about it, but as you
said, tracing requires capital letters there :) )

The rest of the patchset conflicts with [1] but this one doesn't and
is also more important.

[1] https://patchwork.kernel.org/project/linux-trace-kernel/list/?series=999703

Tomas

Re: [PATCH v3 1/3] rtla: fix buffer overflow in actions_parse

[Steven Rostedt]

On Fri, 26 Sep 2025 16:32:52 +0200
Tomas Glozar <tglozar@redhat.com> wrote:


> Could you take this simple fix? (Might require tweaking the starting
> letter "fix" -> "Fix", I don't care that much about it, but as you
> said, tracing requires capital letters there :) )

Yeah, I can update it.

> 
> The rest of the patchset conflicts with [1] but this one doesn't and
> is also more important.
> 
> [1] https://patchwork.kernel.org/project/linux-trace-kernel/list/?series=999703

Should I expect a v4 on patches 2 and 3?

-- Steve

Re: [PATCH v3 1/3] rtla: fix buffer overflow in actions_parse

[Ivan Pravdin]

On Fri, Sep 26, 2025 at 04:32:52PM +0200, Tomas Glozar wrote:
> Steven,
> 
> po 8. 9. 2025 v 4:06 odesílatel Ivan Pravdin
> <ipravdin.official@gmail.com> napsal:
> >
> > Currently, tests 3 and 13-22 in tests/timerlat.t fail with error:
> >
> >     *** buffer overflow detected ***: terminated
> >     timeout: the monitored command dumped core
> >
> > The result of running `sudo make check` is
> >
> >     tests/timerlat.t (Wstat: 0 Tests: 22 Failed: 11)
> >       Failed tests:  3, 13-22
> >     Files=3, Tests=34, 140 wallclock secs ( 0.07 usr  0.01 sys + 27.63 cusr
> >     27.96 csys = 55.67 CPU)
> >     Result: FAIL
> >
> > Fix buffer overflow in actions_parse to avoid this error. After this
> > change, the tests results are
> >
> >     tests/hwnoise.t ... ok
> >     tests/osnoise.t ... ok
> >     tests/timerlat.t .. ok
> >     All tests successful.
> >     Files=3, Tests=34, 186 wallclock secs ( 0.06 usr  0.01 sys + 41.10 cusr
> >     44.38 csys = 85.55 CPU)
> >     Result: PASS
> >
> > Fixes: 6ea082b171e0 ("rtla/timerlat: Add action on threshold feature")
> > Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com>
> > Reviewed-by: Tomas Glozar <tglozar@redhat.com>
> > ---
> >  tools/tracing/rtla/src/actions.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Could you take this simple fix? (Might require tweaking the starting
> letter "fix" -> "Fix", I don't care that much about it, but as you
> said, tracing requires capital letters there :) )
> 
> The rest of the patchset conflicts with [1] but this one doesn't and
> is also more important.
> 
> [1] https://patchwork.kernel.org/project/linux-trace-kernel/list/?series=999703

Thanks Tomas. I will monitor it and rebase my patches once it is merged.

> 
> Tomas
> 

	Ivan Pravdin

[PATCH v3 2/3] rtla: fix -C/--cgroup interface

[Ivan Pravdin]

Currently, user can only specify cgroup to the tracer's thread the
following ways:

    `-C[cgroup]`
    `-C[=cgroup]`
    `--cgroup[=cgroup]`

If user tries to specify cgroup as `-C [cgroup]` or `--cgroup [cgroup]`,
the parser silently fails and rtla's cgroup is used for the tracer
threads.

To make interface more user-friendly, allow user to specify cgroup in
the aforementioned way, i.e. `-C [cgroup]` and `--cgroup [cgroup]`.

Refactor identical logic between -t/--trace and -C/--cgroup into a
common function.

Change documentation to reflect this user interface change.

Fixes: a957cbc02531 ("rtla: Add -C cgroup support")
Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com>
---
 Documentation/tools/rtla/common_options.rst |  2 +-
 tools/tracing/rtla/src/osnoise_hist.c       | 26 ++++++---------------
 tools/tracing/rtla/src/osnoise_top.c        | 26 ++++++---------------
 tools/tracing/rtla/src/timerlat_hist.c      | 26 ++++++---------------
 tools/tracing/rtla/src/timerlat_top.c       | 26 ++++++---------------
 tools/tracing/rtla/src/utils.c              | 26 +++++++++++++++++++++
 tools/tracing/rtla/src/utils.h              |  1 +
 7 files changed, 56 insertions(+), 77 deletions(-)

diff --git a/Documentation/tools/rtla/common_options.rst b/Documentation/tools/rtla/common_options.rst
index 2dc1575210aa..3f292a12b7af 100644
--- a/Documentation/tools/rtla/common_options.rst
+++ b/Documentation/tools/rtla/common_options.rst
@@ -42,7 +42,7 @@
         - *f:prio* - use SCHED_FIFO with *prio*;
         - *d:runtime[us|ms|s]:period[us|ms|s]* - use SCHED_DEADLINE with *runtime* and *period* in nanoseconds.
 
-**-C**, **--cgroup**\[*=cgroup*]
+**-C**, **--cgroup** \[*cgroup*]
 
         Set a *cgroup* to the tracer's threads. If the **-C** option is passed without arguments, the tracer's thread will inherit **rtla**'s *cgroup*. Otherwise, the threads will be placed on the *cgroup* passed to the option.
 
diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c
index 8d579bcee709..1dc39de79d78 100644
--- a/tools/tracing/rtla/src/osnoise_hist.c
+++ b/tools/tracing/rtla/src/osnoise_hist.c
@@ -422,9 +422,9 @@ static void osnoise_hist_usage(char *usage)
 	static const char * const msg[] = {
 		"",
 		"  usage: rtla osnoise hist [-h] [-D] [-d s] [-a us] [-p us] [-r us] [-s us] [-S us] \\",
-		"	  [-T us] [-t[file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] \\",
+		"	  [-T us] [-t [file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] \\",
 		"	  [-c cpu-list] [-H cpu-list] [-P priority] [-b N] [-E N] [--no-header] [--no-summary] \\",
-		"	  [--no-index] [--with-zeros] [-C[=cgroup_name]] [--warm-up]",
+		"	  [--no-index] [--with-zeros] [-C [cgroup_name]] [--warm-up]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us sample is hit",
@@ -435,10 +435,10 @@ static void osnoise_hist_usage(char *usage)
 		"	  -T/--threshold us: the minimum delta to be considered a noise",
 		"	  -c/--cpus cpu-list: list of cpus to run osnoise threads",
 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
-		"	  -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
+		"	  -C/--cgroup [cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
 		"	  -d/--duration time[s|m|h|d]: duration of the session",
 		"	  -D/--debug: print debug info",
-		"	  -t/--trace[file]: save the stopped trace to [file|osnoise_trace.txt]",
+		"	  -t/--trace [file]: save the stopped trace to [file|osnoise_trace.txt]",
 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	     --filter <filter>: enable a trace event filter to the previous -e event",
 		"	     --trigger <trigger>: enable a trace event trigger to the previous -e event",
@@ -559,13 +559,7 @@ static struct osnoise_params
 			break;
 		case 'C':
 			params->cgroup = 1;
-			if (!optarg) {
-				/* will inherit this cgroup */
-				params->cgroup_name = NULL;
-			} else if (*optarg == '=') {
-				/* skip the = */
-				params->cgroup_name = ++optarg;
-			}
+			params->cgroup_name = parse_optional_arg(argc, argv);
 			break;
 		case 'D':
 			config_debug = 1;
@@ -630,14 +624,8 @@ static struct osnoise_params
 			params->threshold = get_llong_from_str(optarg);
 			break;
 		case 't':
-			if (optarg) {
-				if (optarg[0] == '=')
-					params->trace_output = &optarg[1];
-				else
-					params->trace_output = &optarg[0];
-			} else if (optind < argc && argv[optind][0] != '0')
-				params->trace_output = argv[optind];
-			else
+			params->trace_output = parse_optional_arg(argc, argv);
+			if (!params->trace_output)
 				params->trace_output = "osnoise_trace.txt";
 			break;
 		case '0': /* no header */
diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
index 2c12780c8aa9..b3e161536ed8 100644
--- a/tools/tracing/rtla/src/osnoise_top.c
+++ b/tools/tracing/rtla/src/osnoise_top.c
@@ -257,8 +257,8 @@ static void osnoise_top_usage(struct osnoise_params *params, char *usage)
 
 	static const char * const msg[] = {
 		" [-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] [-H cpu-list] [-P priority] [-C[=cgroup_name]] [--warm-up s]",
+		"	  [-T us] [-t [file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] \\",
+		"	  [-c cpu-list] [-H cpu-list] [-P priority] [-C [cgroup_name]] [--warm-up s]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us sample is hit",
@@ -269,10 +269,10 @@ static void osnoise_top_usage(struct osnoise_params *params, char *usage)
 		"	  -T/--threshold us: the minimum delta to be considered a noise",
 		"	  -c/--cpus cpu-list: list of cpus to run osnoise threads",
 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
-		"	  -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
+		"	  -C/--cgroup [cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
 		"	  -d/--duration time[s|m|h|d]: duration of the session",
 		"	  -D/--debug: print debug info",
-		"	  -t/--trace[file]: save the stopped trace to [file|osnoise_trace.txt]",
+		"	  -t/--trace [file]: save the stopped trace to [file|osnoise_trace.txt]",
 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	     --filter <filter>: enable a trace event filter to the previous -e event",
 		"	     --trigger <trigger>: enable a trace event trigger to the previous -e event",
@@ -394,13 +394,7 @@ struct osnoise_params *osnoise_top_parse_args(int argc, char **argv)
 			break;
 		case 'C':
 			params->cgroup = 1;
-			if (!optarg) {
-				/* will inherit this cgroup */
-				params->cgroup_name = NULL;
-			} else if (*optarg == '=') {
-				/* skip the = */
-				params->cgroup_name = ++optarg;
-			}
+			params->cgroup_name = parse_optional_arg(argc, argv);
 			break;
 		case 'D':
 			config_debug = 1;
@@ -460,14 +454,8 @@ struct osnoise_params *osnoise_top_parse_args(int argc, char **argv)
 			params->stop_total_us = get_llong_from_str(optarg);
 			break;
 		case 't':
-			if (optarg) {
-				if (optarg[0] == '=')
-					params->trace_output = &optarg[1];
-				else
-					params->trace_output = &optarg[0];
-			} else if (optind < argc && argv[optind][0] != '-')
-				params->trace_output = argv[optind];
-			else
+			params->trace_output = parse_optional_arg(argc, argv);
+			if (!params->trace_output)
 				params->trace_output = "osnoise_trace.txt";
 			break;
 		case 'T':
diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c
index 9baea1b251ed..ad713dafa3c3 100644
--- a/tools/tracing/rtla/src/timerlat_hist.c
+++ b/tools/tracing/rtla/src/timerlat_hist.c
@@ -713,9 +713,9 @@ static void timerlat_hist_usage(char *usage)
 	char *msg[] = {
 		"",
 		"  usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\",
-		"         [-t[file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
+		"         [-t [file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
 		"	  [-P priority] [-E N] [-b N] [--no-irq] [--no-thread] [--no-header] [--no-summary] \\",
-		"	  [--no-index] [--with-zeros] [--dma-latency us] [-C[=cgroup_name]] [--no-aa] [--dump-task] [-u|-k]",
+		"	  [--no-index] [--with-zeros] [--dma-latency us] [-C [cgroup_name]] [--no-aa] [--dump-task] [-u|-k]",
 		"	  [--warm-up s] [--deepest-idle-state n]",
 		"",
 		"	  -h/--help: print this menu",
@@ -726,11 +726,11 @@ static void timerlat_hist_usage(char *usage)
 		"	  -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
 		"	  -c/--cpus cpus: run the tracer only on the given cpus",
 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
-		"	  -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
+		"	  -C/--cgroup [cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
 		"	  -d/--duration time[m|h|d]: duration of the session in seconds",
 		"	     --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
 		"	  -D/--debug: print debug info",
-		"	  -t/--trace[file]: save the stopped trace to [file|timerlat_trace.txt]",
+		"	  -t/--trace [file]: save the stopped trace to [file|timerlat_trace.txt]",
 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	     --filter <filter>: enable a trace event filter to the previous -e event",
 		"	     --trigger <trigger>: enable a trace event trigger to the previous -e event",
@@ -885,13 +885,7 @@ static struct timerlat_params
 			break;
 		case 'C':
 			params->cgroup = 1;
-			if (!optarg) {
-				/* will inherit this cgroup */
-				params->cgroup_name = NULL;
-			} else if (*optarg == '=') {
-				/* skip the = */
-				params->cgroup_name = ++optarg;
-			}
+			params->cgroup_name = parse_optional_arg(argc, argv);
 			break;
 		case 'b':
 			params->bucket_size = get_llong_from_str(optarg);
@@ -962,14 +956,8 @@ static struct timerlat_params
 			params->stop_total_us = get_llong_from_str(optarg);
 			break;
 		case 't':
-			if (optarg) {
-				if (optarg[0] == '=')
-					trace_output = &optarg[1];
-				else
-					trace_output = &optarg[0];
-			} else if (optind < argc && argv[optind][0] != '-')
-				trace_output = argv[optind];
-			else
+			trace_output = parse_optional_arg(argc, argv);
+			if (!trace_output)
 				trace_output = "timerlat_trace.txt";
 			break;
 		case 'u':
diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c
index c80b81c0b4da..7f1885018624 100644
--- a/tools/tracing/rtla/src/timerlat_top.c
+++ b/tools/tracing/rtla/src/timerlat_top.c
@@ -480,8 +480,8 @@ static void timerlat_top_usage(char *usage)
 	static const char *const msg[] = {
 		"",
 		"  usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\",
-		"	  [[-t[file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
-		"	  [-P priority] [--dma-latency us] [--aa-only us] [-C[=cgroup_name]] [-u|-k] [--warm-up s] [--deepest-idle-state n]",
+		"	  [[-t [file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
+		"	  [-P priority] [--dma-latency us] [--aa-only us] [-C [cgroup_name]] [-u|-k] [--warm-up s] [--deepest-idle-state n]",
 		"",
 		"	  -h/--help: print this menu",
 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
@@ -492,11 +492,11 @@ static void timerlat_top_usage(char *usage)
 		"	  -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
 		"	  -c/--cpus cpus: run the tracer only on the given cpus",
 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
-		"	  -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
+		"	  -C/--cgroup [cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
 		"	  -d/--duration time[s|m|h|d]: duration of the session",
 		"	  -D/--debug: print debug info",
 		"	     --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
-		"	  -t/--trace[file]: save the stopped trace to [file|timerlat_trace.txt]",
+		"	  -t/--trace [file]: save the stopped trace to [file|timerlat_trace.txt]",
 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
 		"	     --filter <command>: enable a trace event filter to the previous -e event",
 		"	     --trigger <command>: enable a trace event trigger to the previous -e event",
@@ -650,13 +650,7 @@ static struct timerlat_params
 			break;
 		case 'C':
 			params->cgroup = 1;
-			if (!optarg) {
-				/* will inherit this cgroup */
-				params->cgroup_name = NULL;
-			} else if (*optarg == '=') {
-				/* skip the = */
-				params->cgroup_name = ++optarg;
-			}
+			params->cgroup_name = optarg;
 			break;
 		case 'D':
 			config_debug = 1;
@@ -719,14 +713,8 @@ static struct timerlat_params
 			params->stop_total_us = get_llong_from_str(optarg);
 			break;
 		case 't':
-			if (optarg) {
-				if (optarg[0] == '=')
-					trace_output = &optarg[1];
-				else
-					trace_output = &optarg[0];
-			} else if (optind < argc && argv[optind][0] != '-')
-				trace_output = argv[optind];
-			else
+			trace_output = parse_optional_arg(argc, argv);
+			if (!trace_output)
 				trace_output = "timerlat_trace.txt";
 			break;
 		case 'u':
diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c
index d6ab15dcb490..bd5f34b44648 100644
--- a/tools/tracing/rtla/src/utils.c
+++ b/tools/tracing/rtla/src/utils.c
@@ -959,3 +959,29 @@ int auto_house_keeping(cpu_set_t *monitored_cpus)
 
 	return 1;
 }
+
+/**
+ * parse_optional_arg - Parse optional argument value
+ *
+ * Parse optional argument value, which can be in the form of:
+ * -sarg, -s/--long=arg, -s/--long arg
+ *
+ * Returns arg value if found, NULL otherwise.
+ */
+char *parse_optional_arg(int argc, char **argv)
+{
+	if (optarg) {
+		if (optarg[0] == '=') {
+			/* skip the = */
+			return &optarg[1];
+		} else {
+			return optarg;
+		}
+	/* parse argument of form -s [arg] and --long [arg]*/
+	} else if (optind < argc && argv[optind][0] != '-') {
+		/* consume optind */
+		return argv[optind++];
+	} else {
+		return NULL;
+	}
+}
diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h
index a2a6f89f342d..d8d83abf0f0d 100644
--- a/tools/tracing/rtla/src/utils.h
+++ b/tools/tracing/rtla/src/utils.h
@@ -24,6 +24,7 @@ long parse_seconds_duration(char *val);
 void get_duration(time_t start_time, char *output, int output_size);
 
 int parse_cpu_list(char *cpu_list, char **monitored_cpus);
+char *parse_optional_arg(int argc, char **argv);
 long long get_llong_from_str(char *start);
 
 static inline void
-- 
2.48.1

Re: [PATCH v3 2/3] rtla: fix -C/--cgroup interface

[Tomas Glozar]

po 8. 9. 2025 v 4:06 odesílatel Ivan Pravdin
<ipravdin.official@gmail.com> napsal:
>
> Refactor identical logic between -t/--trace and -C/--cgroup into a
> common function.
>
> Change documentation to reflect this user interface change.
>

Looks good to me, thank you for implementing the refactoring, now that
the logic is shared.

Reviewed-by: Tomas Glozar <tglozar@redhat.com>

Tomas

[PATCH v3 3/3] rtla: fix -a overriding -t argument

[Ivan Pravdin]

When running rtla as

    `rtla <timerlat|osnoise> <top|hist> -t custom_file.txt -a 100`

-a options override trace output filename specified by -t option.
Running the command above will create <timerlat|osnoise>_trace.txt file
instead of custom_file.txt. Fix this by making sure that -a option does
not override trace output filename even if it's passed after trace
output filename is specified.

Fixes: 173a3b014827 ("rtla/timerlat: Add the automatic trace option")
Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com>
---
 tools/tracing/rtla/src/osnoise_hist.c  | 3 ++-
 tools/tracing/rtla/src/osnoise_top.c   | 3 ++-
 tools/tracing/rtla/src/timerlat_hist.c | 3 ++-
 tools/tracing/rtla/src/timerlat_top.c  | 3 ++-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c
index 1dc39de79d78..3aa74affac26 100644
--- a/tools/tracing/rtla/src/osnoise_hist.c
+++ b/tools/tracing/rtla/src/osnoise_hist.c
@@ -543,7 +543,8 @@ static struct osnoise_params
 			params->threshold = 1;
 
 			/* set trace */
-			params->trace_output = "osnoise_trace.txt";
+			if (!params->trace_output)
+				params->trace_output = "osnoise_trace.txt";
 
 			break;
 		case 'b':
diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
index b3e161536ed8..6bcb8d10c342 100644
--- a/tools/tracing/rtla/src/osnoise_top.c
+++ b/tools/tracing/rtla/src/osnoise_top.c
@@ -383,7 +383,8 @@ struct osnoise_params *osnoise_top_parse_args(int argc, char **argv)
 			params->threshold = 1;
 
 			/* set trace */
-			params->trace_output = "osnoise_trace.txt";
+			if (!params->trace_output)
+				params->trace_output = "osnoise_trace.txt";
 
 			break;
 		case 'c':
diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c
index ad713dafa3c3..f845d5fa8141 100644
--- a/tools/tracing/rtla/src/timerlat_hist.c
+++ b/tools/tracing/rtla/src/timerlat_hist.c
@@ -874,7 +874,8 @@ static struct timerlat_params
 			params->print_stack = auto_thresh;
 
 			/* set trace */
-			trace_output = "timerlat_trace.txt";
+			if (!trace_output)
+				trace_output = "timerlat_trace.txt";
 
 			break;
 		case 'c':
diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c
index 7f1885018624..42d85ea2e996 100644
--- a/tools/tracing/rtla/src/timerlat_top.c
+++ b/tools/tracing/rtla/src/timerlat_top.c
@@ -625,7 +625,8 @@ static struct timerlat_params
 			params->print_stack = auto_thresh;
 
 			/* set trace */
-			trace_output = "timerlat_trace.txt";
+			if (!trace_output)
+				trace_output = "timerlat_trace.txt";
 
 			break;
 		case '5':
-- 
2.48.1

Re: [PATCH v3 3/3] rtla: fix -a overriding -t argument

[Tomas Glozar]

po 8. 9. 2025 v 4:06 odesílatel Ivan Pravdin
<ipravdin.official@gmail.com> napsal:
>
> When running rtla as
>
>     `rtla <timerlat|osnoise> <top|hist> -t custom_file.txt -a 100`
>
> -a options override trace output filename specified by -t option.
> Running the command above will create <timerlat|osnoise>_trace.txt file
> instead of custom_file.txt. Fix this by making sure that -a option does
> not override trace output filename even if it's passed after trace
> output filename is specified.
>
> Fixes: 173a3b014827 ("rtla/timerlat: Add the automatic trace option")
> Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com>

This part is good, the only problematic bit was the clear_terminal stuff.

Reviewed-by: Tomas Glozar <tglozar@redhat.com>

Tomas