Document the 'perf test -w' workloads functionality

From: Arnaldo Carvalho de Melo <[email protected]>

Hi,

I noticed that the 'perf test -w' code wasn't well exposed, so
add a '-w --list' option to list the existing workloads and document it in the 'perf test' man page.

- Arnaldo

Arnaldo Carvalho de Melo (3):
perf test: Introduce workloads__for_each()
perf test: Introduce '-w --list' to list the available workloads perf test: Document the -w/--workload option

 tools/perf/Documentation/perf-test.txt |  6 ++++++
 tools/perf/tests/builtin-test.c        | 25 +++++++++++++++++++++----
 2 files changed, 27 insertions(+), 4 deletions(-)

2.47.0

From: Arnaldo Carvalho de Melo <[email protected]>

And use it in run_workload().

Testing it:

  root@x1:~# perf trace -e *landlock* perf test -w landlock
       0.000 ( 0.015 ms): :1274331/1274331 landlock_add_rule(ruleset_fd: 11, rule_type: LANDLOCK_RULE_PATH_BENEATH, rule_attr: 0x7ffd3fea55e0, flags: 45) = -1 EINVAL (Invalid argument)
       0.018 ( 0.003 ms): :1274331/1274331 landlock_add_rule(ruleset_fd: 11, rule_type: LANDLOCK_RULE_NET_PORT, rule_attr: 0x7ffd3fea55f0, flags: 45) = -1 EINVAL (Invalid argument)
  root@x1:~# perf test -w bla
  No workload found: bla
  root@x1:~#

---
 tools/perf/tests/builtin-test.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

index 470a9709427ddaad..2201f7ed432ce9f2 100644
@@ -155,6 +155,9 @@ static struct test_workload *workloads[] = {
 	&workload__landlock,
 };
 
+#define workloads__for_each(workload) \
+	for (unsigned i = 0; i < ARRAY_SIZE(workloads) && ({ workload = workloads[i]; 1; }); i++)
+
 static int num_subtests(const struct test_suite *t)
 {
 	int num;

@@ -504,11 +507,9 @@ static int perf_test__list(int argc, const char **argv)
 
 static int run_workload(const char *work, int argc, const char **argv)
 {
-	unsigned int i = 0;
 	struct test_workload *twl;
 
-	for (i = 0; i < ARRAY_SIZE(workloads); i++) {
-		twl = workloads[i];
+	workloads__for_each(twl) {
 		if (!strcmp(twl->name, work))
 			return twl->func(argc, argv);
 	}

2.47.0

From: Arnaldo Carvalho de Melo <[email protected]>

Using it:

  $ perf test -w noplop
  No workload found: noplop
  $
  $ perf test -w
   Error: switch `w' requires a value
   Usage: perf test [<options>] [{list <test-name-fragment>|[<test-name-fragments>|<test-numbers>]}]

-w, --workload <work>
workload to run for testing, use '-w --list' to list the available ones.
$

  $ perf test -w --list
  noploop
  thloop
  leafloop
  sqrtloop
  brstack
  datasym
  landlock
  $

Would be good at some point to have a description in 'struct test_workload'.

---
 tools/perf/tests/builtin-test.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

index 2201f7ed432ce9f2..f0d10d2dd0d40019 100644
@@ -505,10 +505,26 @@ static int perf_test__list(int argc, const char **argv)
 	return 0;
 }
 
+static int workloads__fprintf_list(FILE *fp)
+{
+	struct test_workload *twl;
+	int printed = 0;
+
+	workloads__for_each(twl)
+		printed += fprintf(fp, "%s\n", twl->name);
+
+	return printed;
+}
+
 static int run_workload(const char *work, int argc, const char **argv)
 {
 	struct test_workload *twl;
 
+	if (!strcmp(work, "--list")) {
+		workloads__fprintf_list(stdout);
+		return 0;
+	}
+
 	workloads__for_each(twl) {
 		if (!strcmp(twl->name, work))
 			return twl->func(argc, argv);

@@ -544,7 +560,7 @@ int cmd_test(int argc, const char **argv)
 	OPT_BOOLEAN('p', "parallel", &parallel, "Run the tests in parallel"),
 	OPT_BOOLEAN('S', "sequential", &sequential,
 		    "Run the tests one after another rather than in parallel"),
-	OPT_STRING('w', "workload", &workload, "work", "workload to run for testing"),
+	OPT_STRING('w', "workload", &workload, "work", "workload to run for testing, use '-w --list' to list the available ones."),
 	OPT_STRING(0, "dso", &dso_to_test, "dso", "dso to test"),
 	OPT_STRING(0, "objdump", &test_objdump_path, "path",
 		   "objdump binary to use for disassembly and annotations"),

2.47.0

From: Arnaldo Carvalho de Melo <[email protected]>

Wasn't documented so far, mention that it is mostly used in the shell regression tests.

---
 tools/perf/Documentation/perf-test.txt | 6 ++++++
 1 file changed, 6 insertions(+)

index 9acb8d1f658890e9..e03c1cabdcd37594 100644
@@ -48,3 +48,9 @@ OPTIONS
 
 --dso::
 	Specify a DSO for the "Symbols" test.
+
+-w::
+--workload=::
+	Run a built-in workload, to list them use '-w --list', current ones include:
+	noploop, thloop, leafloop, sqrtloop, brstack, datasym and landlock.
+	Used with the shell script regression tests.

2.47.0