On Sun, Oct 01, 2023 at 12:37:40PM -0700, Andrew Morton wrote:
> selftests-proc-add-proc-pid-statm-output-validation.patch
> Add /proc/${pid}/statm validation
>
> /proc/$(pid)/statm output is expected to be:
> "0 0 0 * 0 0 0\n"
> Here * can be any value
>
> Read output of /proc/$(pid)/statm
> and compare length of output is
> equal or greater than expected output
> --- a/tools/testing/selftests/proc/proc-empty-vm.c~selftests-proc-add-proc-pid-statm-output-validation
> +++ a/tools/testing/selftests/proc/proc-empty-vm.c
> @@ -303,6 +303,37 @@ static int test_proc_pid_smaps_rollup(pi
> }
> }
>
> +static const char g_statm[] = "0 0 0 * 0 0 0\n";
This is both unreliable and incorrect.
4th value is "end_code - start_code" when exec is done which could be
anything not 1-digit number (although unlikely).
Testing for strlen is simply too weak of a test.
> +static int test_proc_pid_statm(pid_t pid)
> +{
> + char buf[4096];
> +
> + snprintf(buf, sizeof(buf), "/proc/%u/statm", pid);
> +
> + int fd = open(buf, O_RDONLY);
> +
> + if (fd == -1) {
> + if (errno == ENOENT) {
> + /*
> + * /proc/${pid}/statm is under CONFIG_PROC_PAGE_MONITOR,
> + * it doesn't necessarily exist.
> + */
> + return EXIT_SUCCESS;
> + }
> + perror("open /proc/${pid}/statm");
> + return EXIT_FAILURE;
> + } else {
> + ssize_t rv = read(fd, buf, sizeof(buf));
> +
> + close(fd);
> + size_t len = strlen(g_statm);
> +
> + assert(rv >= len);
> + return EXIT_SUCCESS;
> + }
> +}
> +
> int main(void)
> {
> int rv = EXIT_SUCCESS;
> @@ -389,11 +420,8 @@ int main(void)
> if (rv == EXIT_SUCCESS) {
> rv = test_proc_pid_smaps_rollup(pid);
> }
> - /*
> - * TODO test /proc/${pid}/statm, task_statm()
> - * ->start_code, ->end_code aren't updated by munmap().
> - * Output can be "0 0 0 2 0 0 0\n" where "2" can be anything.
> - */
> + if (rv == EXIT_SUCCESS)
> + rv = test_proc_pid_statm(pid);
>
> /* Cut the rope. */
On Mon, Oct 02, 2023 at 03:38:25PM +0300, Alexey Dobriyan wrote:
> On Sun, Oct 01, 2023 at 12:37:40PM -0700, Andrew Morton wrote:
> > selftests-proc-add-proc-pid-statm-output-validation.patch
>
> > Add /proc/${pid}/statm validation
> >
> > /proc/$(pid)/statm output is expected to be:
> > "0 0 0 * 0 0 0\n"
> > Here * can be any value
> >
> > Read output of /proc/$(pid)/statm
> > and compare length of output is
> > equal or greater than expected output
>
> > --- a/tools/testing/selftests/proc/proc-empty-vm.c~selftests-proc-add-proc-pid-statm-output-validation
> > +++ a/tools/testing/selftests/proc/proc-empty-vm.c
> > @@ -303,6 +303,37 @@ static int test_proc_pid_smaps_rollup(pi
> > }
> > }
> >
> > +static const char g_statm[] = "0 0 0 * 0 0 0\n";
>
> This is both unreliable and incorrect.
>
> 4th value is "end_code - start_code" when exec is done which could be
> anything not 1-digit number (although unlikely).
>
> Testing for strlen is simply too weak of a test.
>
> > +static int test_proc_pid_statm(pid_t pid)
> > +{
> > + char buf[4096];
> > +
> > + snprintf(buf, sizeof(buf), "/proc/%u/statm", pid);
> > +
> > + int fd = open(buf, O_RDONLY);
> > +
> > + if (fd == -1) {
> > + if (errno == ENOENT) {
> > + /*
> > + * /proc/${pid}/statm is under CONFIG_PROC_PAGE_MONITOR,
> > + * it doesn't necessarily exist.
> > + */
> > + return EXIT_SUCCESS;
> > + }
> > + perror("open /proc/${pid}/statm");
> > + return EXIT_FAILURE;
> > + } else {
> > + ssize_t rv = read(fd, buf, sizeof(buf));
> > +
> > + close(fd);
> > + size_t len = strlen(g_statm);
> > +
> > + assert(rv >= len);
> > + return EXIT_SUCCESS;
> > + }
> > +}
> > +
> > int main(void)
> > {
> > int rv = EXIT_SUCCESS;
> > @@ -389,11 +420,8 @@ int main(void)
> > if (rv == EXIT_SUCCESS) {
> > rv = test_proc_pid_smaps_rollup(pid);
> > }
> > - /*
> > - * TODO test /proc/${pid}/statm, task_statm()
> > - * ->start_code, ->end_code aren't updated by munmap().
> > - * Output can be "0 0 0 2 0 0 0\n" where "2" can be anything.
> > - */
> > + if (rv == EXIT_SUCCESS)
> > + rv = test_proc_pid_statm(pid);
> >
> > /* Cut the rope. */
Hi Alexey,
Thanks for reviewing the changes.
I assume below output of /proc/${procid}/statm
can be assumed as mentioned below:
static const char g_statm[] = "0 0 0 * 0 0 0\n"
If 0 is correct at their places, only issue is *,
whose value will be single digit or could change?
If this assumption is correct, i can change the
validation to handle 4th postion, and remaining
place will validate if it has zero or not,
and will send another patch?
Thanks,
Swarup
Add /proc/${pid}/statm validation
/proc/$(pid)/statm output is expected to be:
"0 0 0 * 0 0 0\n"
Here * can be any value
Read output of /proc/$(pid)/statm
and check except for 4th position,
all other positions have value zero.
Signed-off-by: Swarup Laxman Kotiaklapudi <[email protected]>
---
Changes in V2:
- 4th field if zero it will assert
- field other than 4th field is checked for zero value
- clean up of function test_proc_pid_statm()
Changes in V1:
- added new function test_proc_pid_statm()
tools/testing/selftests/proc/proc-empty-vm.c | 57 ++++++++++++++++++--
1 file changed, 52 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/proc/proc-empty-vm.c b/tools/testing/selftests/proc/proc-empty-vm.c
index b16c13688b88..1b5b48445e0f 100644
--- a/tools/testing/selftests/proc/proc-empty-vm.c
+++ b/tools/testing/selftests/proc/proc-empty-vm.c
@@ -302,6 +302,56 @@ static int test_proc_pid_smaps_rollup(pid_t pid)
}
}
+static int test_proc_pid_statm(pid_t pid)
+{
+ char buf[4096];
+ char *tok;
+ char *string;
+ int non_zero_value_indx = 4;
+ int i = 1;
+
+ snprintf(buf, sizeof(buf), "/proc/%u/statm", pid);
+
+ /*
+ * Output can be "0 0 0 2 0 0 0\n" where "2" can be anything.
+ */
+ int fd = open(buf, O_RDONLY);
+
+ if (fd == -1) {
+ if (errno == ENOENT) {
+ /*
+ * /proc/${pid}/statm is under CONFIG_PROC_PAGE_MONITOR,
+ * it doesn't necessarily exist.
+ */
+ return EXIT_SUCCESS;
+ }
+ perror("open /proc/${pid}/statm");
+ return EXIT_FAILURE;
+ } else {
+ ssize_t rv = read(fd, buf, sizeof(buf));
+
+ close(fd);
+ assert(rv);
+ string = buf;
+
+ while ((tok = strsep(&string, " ")) != NULL) {
+ if (i == non_zero_value_indx) {
+ if (!strncmp(tok, "0", 1))
+ goto err_statm;
+ } else {
+ if (strncmp(tok, "0", 1))
+ goto err_statm;
+ }
+ i++;
+ }
+ }
+
+ return EXIT_SUCCESS;
+
+err_statm:
+ assert(0);
+}
+
int main(void)
{
int rv = EXIT_SUCCESS;
@@ -388,11 +438,8 @@ int main(void)
if (rv == EXIT_SUCCESS) {
rv = test_proc_pid_smaps_rollup(pid);
}
- /*
- * TODO test /proc/${pid}/statm, task_statm()
- * ->start_code, ->end_code aren't updated by munmap().
- * Output can be "0 0 0 2 0 0 0\n" where "2" can be anything.
- */
+ if (rv == EXIT_SUCCESS)
+ rv = test_proc_pid_statm(pid);
/* Cut the rope. */
int wstatus;
--
2.34.1