+ selftests-proc-add-proc-pid-statm-output-validation.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: selftests: proc: add /proc/$(pid)/statm output validation
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     selftests-proc-add-proc-pid-statm-output-validation.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-proc-add-proc-pid-statm-output-validation.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Swarup Laxman Kotiaklapudi <swarupkotikalapudi@gmail.com>
Subject: selftests: proc: add /proc/$(pid)/statm output validation
Date: Sun, 1 Oct 2023 22:38:16 +0530

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

Link: https://lkml.kernel.org/r/20231001170816.28241-1-swarupkotikalapudi@gmail.com
Signed-off-by: Swarup Laxman Kotiaklapudi <swarupkotikalapudi@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/proc/proc-empty-vm.c |   38 ++++++++++++++---
 1 file changed, 33 insertions(+), 5 deletions(-)

--- 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";
+
+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. */
 		int wstatus;
_

Patches currently in -mm which might be from swarupkotikalapudi@gmail.com are

selftests-proc-add-proc-pid-statm-output-validation.patch