Re: [PATCH] perf test: iterate over shell tests in alphabetical order

From: Arnaldo Carvalho de Melo
Date: Wed May 26 2021 - 09:58:50 EST


Em Tue, May 25, 2021 at 04:25:48PM -0700, Ian Rogers escreveu:
> On Tue, May 25, 2021 at 4:08 PM Riccardo Mancini <rickyman7@xxxxxxxxx> wrote:
> >
> > for_each_shell_test macro iterated over all shell tests in the directory
> > using readdir, which does not guarantee any ordering, causing
> > problems on certain fs. However, the order in which they are visited
> > determines the id of the test, in case one wants to run a single test.
> >
> > This patch replaces readdir with scandir using alphabetical sorting.
> > This guarantees that, given the same set of tests, all machines will
> > see the tests in the same order, and, thus, that test ids are
> > consistent.
> >
> > Signed-off-by: Riccardo Mancini <rickyman7@xxxxxxxxx>
> > Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> > Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> > Cc: Ian Rogers <irogers@xxxxxxxxxx>
>
> Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks, applied and also added this, which I think it appropriate in
this case, no?

Reported-by: Ian Rogers <irogers@xxxxxxxxxx>

- Arnaldo

> > ---
> > tools/perf/tests/builtin-test.c | 38 ++++++++++++++++++---------------
> > 1 file changed, 21 insertions(+), 17 deletions(-)
> >
> > diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
> > index c4b888f18e9ca..cbbfe48ab8029 100644
> > --- a/tools/perf/tests/builtin-test.c
> > +++ b/tools/perf/tests/builtin-test.c
> > @@ -510,8 +510,8 @@ static const char *shell_test__description(char *description, size_t size,
> > return description ? strim(description + 1) : NULL;
> > }
> >
> > -#define for_each_shell_test(dir, base, ent) \
> > - while ((ent = readdir(dir)) != NULL) \
> > +#define for_each_shell_test(entlist, nr, base, ent) \
> > + for (int __i = 0; __i < nr && (ent = entlist[__i]); __i++) \
>
> I think this declaration of __i is okay as C99 allows declarations
> here, but generally I don't see this style in the kernel.
>
> Thanks,
> Ian
>
> > if (!is_directory(base, ent) && ent->d_name[0] != '.')
> >
> > static const char *shell_tests__dir(char *path, size_t size)
> > @@ -538,8 +538,9 @@ static const char *shell_tests__dir(char *path, size_t size)
> >
> > static int shell_tests__max_desc_width(void)
> > {
> > - DIR *dir;
> > + struct dirent **entlist;
> > struct dirent *ent;
> > + int n_dirs;
> > char path_dir[PATH_MAX];
> > const char *path = shell_tests__dir(path_dir, sizeof(path_dir));
> > int width = 0;
> > @@ -547,11 +548,11 @@ static int shell_tests__max_desc_width(void)
> > if (path == NULL)
> > return -1;
> >
> > - dir = opendir(path);
> > - if (!dir)
> > + n_dirs = scandir(path, &entlist, NULL, alphasort);
> > + if (n_dirs == -1)
> > return -1;
> >
> > - for_each_shell_test(dir, path, ent) {
> > + for_each_shell_test(entlist, n_dirs, path, ent) {
> > char bf[256];
> > const char *desc = shell_test__description(bf, sizeof(bf), path, ent->d_name);
> >
> > @@ -563,7 +564,8 @@ static int shell_tests__max_desc_width(void)
> > }
> > }
> >
> > - closedir(dir);
> > + free(entlist);
> > +
> > return width;
> > }
> >
> > @@ -589,8 +591,9 @@ static int shell_test__run(struct test *test, int subdir __maybe_unused)
> >
> > static int run_shell_tests(int argc, const char *argv[], int i, int width)
> > {
> > - DIR *dir;
> > + struct dirent **entlist;
> > struct dirent *ent;
> > + int n_dirs;
> > char path_dir[PATH_MAX];
> > struct shell_test st = {
> > .dir = shell_tests__dir(path_dir, sizeof(path_dir)),
> > @@ -599,14 +602,14 @@ static int run_shell_tests(int argc, const char *argv[], int i, int width)
> > if (st.dir == NULL)
> > return -1;
> >
> > - dir = opendir(st.dir);
> > - if (!dir) {
> > + n_dirs = scandir(st.dir, &entlist, NULL, alphasort);
> > + if (n_dirs == -1) {
> > pr_err("failed to open shell test directory: %s\n",
> > st.dir);
> > return -1;
> > }
> >
> > - for_each_shell_test(dir, st.dir, ent) {
> > + for_each_shell_test(entlist, n_dirs, st.dir, ent) {
> > int curr = i++;
> > char desc[256];
> > struct test test = {
> > @@ -623,7 +626,7 @@ static int run_shell_tests(int argc, const char *argv[], int i, int width)
> > test_and_print(&test, false, -1);
> > }
> >
> > - closedir(dir);
> > + free(entlist);
> > return 0;
> > }
> >
> > @@ -722,19 +725,20 @@ static int __cmd_test(int argc, const char *argv[], struct intlist *skiplist)
> >
> > static int perf_test__list_shell(int argc, const char **argv, int i)
> > {
> > - DIR *dir;
> > + struct dirent **entlist;
> > struct dirent *ent;
> > + int n_dirs;
> > char path_dir[PATH_MAX];
> > const char *path = shell_tests__dir(path_dir, sizeof(path_dir));
> >
> > if (path == NULL)
> > return -1;
> >
> > - dir = opendir(path);
> > - if (!dir)
> > + n_dirs = scandir(path, &entlist, NULL, alphasort);
> > + if (n_dirs == -1)
> > return -1;
> >
> > - for_each_shell_test(dir, path, ent) {
> > + for_each_shell_test(entlist, n_dirs, path, ent) {
> > int curr = i++;
> > char bf[256];
> > struct test t = {
> > @@ -747,7 +751,7 @@ static int perf_test__list_shell(int argc, const char **argv, int i)
> > pr_info("%2d: %s\n", i, t.desc);
> > }
> >
> > - closedir(dir);
> > + free(entlist);
> > return 0;
> > }
> >
> > --
> > 2.31.1
> >

--

- Arnaldo