Re: [PATCH v1 3/4] selftests/mm: Extract read_sysfs and write_sysfs into vm_util
From: Pu Lehui
Date: Tue Jun 03 2025 - 03:18:22 EST
On 2025/5/30 19:48, Lorenzo Stoakes wrote:
On Thu, May 29, 2025 at 03:56:49PM +0000, Pu Lehui wrote:
From: Pu Lehui <pulehui@xxxxxxxxxx>
Extract read_sysfs and write_sysfs into vm_util. Meanwhile, rename
the function in thuge-gen that has the same name as read_sysfs.
Nice!
Signed-off-by: Pu Lehui <pulehui@xxxxxxxxxx>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
---
tools/testing/selftests/mm/ksm_tests.c | 32 ++--------------------
tools/testing/selftests/mm/thuge-gen.c | 6 ++--
tools/testing/selftests/mm/vm_util.c | 38 ++++++++++++++++++++++++++
tools/testing/selftests/mm/vm_util.h | 2 ++
4 files changed, 45 insertions(+), 33 deletions(-)
diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c
index dcdd5bb20f3d..e80deac1436b 100644
--- a/tools/testing/selftests/mm/ksm_tests.c
+++ b/tools/testing/selftests/mm/ksm_tests.c
@@ -58,40 +58,12 @@ int debug;
static int ksm_write_sysfs(const char *file_path, unsigned long val)
{
- FILE *f = fopen(file_path, "w");
-
- if (!f) {
- fprintf(stderr, "f %s\n", file_path);
- perror("fopen");
- return 1;
- }
- if (fprintf(f, "%lu", val) < 0) {
- perror("fprintf");
- fclose(f);
- return 1;
- }
- fclose(f);
-
- return 0;
+ return write_sysfs(file_path, val);
}
static int ksm_read_sysfs(const char *file_path, unsigned long *val)
{
- FILE *f = fopen(file_path, "r");
-
- if (!f) {
- fprintf(stderr, "f %s\n", file_path);
- perror("fopen");
- return 1;
- }
- if (fscanf(f, "%lu", val) != 1) {
- perror("fscanf");
- fclose(f);
- return 1;
- }
- fclose(f);
-
- return 0;
+ return read_sysfs(file_path, val);
}
static void ksm_print_sysfs(void)
diff --git a/tools/testing/selftests/mm/thuge-gen.c b/tools/testing/selftests/mm/thuge-gen.c
index a41bc1234b37..95b6f043a3cb 100644
--- a/tools/testing/selftests/mm/thuge-gen.c
+++ b/tools/testing/selftests/mm/thuge-gen.c
@@ -77,7 +77,7 @@ void show(unsigned long ps)
system(buf);
}
-unsigned long read_sysfs(int warn, char *fmt, ...)
+unsigned long thuge_read_sysfs(int warn, char *fmt, ...)
{
I wonder if we could update these to use the newly shared functions?
Not a big deal though, perhaps a bit out of scope here, more of a nice-to-have.
Hi Lorenzo, Andrew,
Yep, we can do it more. But, actually, I am not sure about the merge
process of mm module. Do I need to resend the whole series or just the
diff below?
From 13ecf9d66a0068d520be955e3ca8d9c0dc9d8393 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui@xxxxxxxxxx>
Date: Tue, 3 Jun 2025 06:50:43 +0000
Subject: [PATCH] selftests/mm: Use generic read_sysfs in thuge-gen test
Use generic read_sysfs in thuge-gen test.
Signed-off-by: Pu Lehui <pulehui@xxxxxxxxxx>
---
tools/testing/selftests/mm/thuge-gen.c | 37 +++++++-------------------
1 file changed, 9 insertions(+), 28 deletions(-)
diff --git a/tools/testing/selftests/mm/thuge-gen.c
b/tools/testing/selftests/mm/thuge-gen.c
index 95b6f043a3cb..5a32ed0ba26c 100644
--- a/tools/testing/selftests/mm/thuge-gen.c
+++ b/tools/testing/selftests/mm/thuge-gen.c
@@ -77,40 +77,19 @@ void show(unsigned long ps)
system(buf);
}
-unsigned long thuge_read_sysfs(int warn, char *fmt, ...)
+unsigned long read_free(unsigned long ps)
{
- char *line = NULL;
- size_t linelen = 0;
- char buf[100];
- FILE *f;
- va_list ap;
unsigned long val = 0;
+ char buf[100];
- va_start(ap, fmt);
- vsnprintf(buf, sizeof buf, fmt, ap);
- va_end(ap);
+ snprintf(buf, sizeof buf,
+ "/sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
+ ps >> 10);
+ read_sysfs(buf, &val);
- f = fopen(buf, "r");
- if (!f) {
- if (warn)
- ksft_print_msg("missing %s\n", buf);
- return 0;
- }
- if (getline(&line, &linelen, f) > 0) {
- sscanf(line, "%lu", &val);
- }
- fclose(f);
- free(line);
return val;
}
-unsigned long read_free(unsigned long ps)
-{
- return thuge_read_sysfs(ps != getpagesize(),
- "/sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
- ps >> 10);
-}
-
void test_mmap(unsigned long size, unsigned flags)
{
char *map;
@@ -173,6 +152,7 @@ void test_shmget(unsigned long size, unsigned flags)
void find_pagesizes(void)
{
unsigned long largest = getpagesize();
+ unsigned long shmmax_val = 0;
int i;
glob_t g;
@@ -195,7 +175,8 @@ void find_pagesizes(void)
}
globfree(&g);
- if (thuge_read_sysfs(0, "/proc/sys/kernel/shmmax") < NUM_PAGES * largest)
+ read_sysfs("/proc/sys/kernel/shmmax", &shmmax_val);
+ if (shmmax_val < NUM_PAGES * largest)
ksft_exit_fail_msg("Please do echo %lu > /proc/sys/kernel/shmmax",
largest * NUM_PAGES);
--
2.34.1
char *line = NULL;
size_t linelen = 0;
@@ -106,7 +106,7 @@ unsigned long read_sysfs(int warn, char *fmt, ...)
unsigned long read_free(unsigned long ps)
{
- return read_sysfs(ps != getpagesize(),
+ return thuge_read_sysfs(ps != getpagesize(),
"/sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
ps >> 10);
}
@@ -195,7 +195,7 @@ void find_pagesizes(void)
}
globfree(&g);
- if (read_sysfs(0, "/proc/sys/kernel/shmmax") < NUM_PAGES * largest)
+ if (thuge_read_sysfs(0, "/proc/sys/kernel/shmmax") < NUM_PAGES * largest)
ksft_exit_fail_msg("Please do echo %lu > /proc/sys/kernel/shmmax",
largest * NUM_PAGES);
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index 1357e2d6a7b6..d899c272e0ee 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -486,3 +486,41 @@ int close_procmap(struct procmap_fd *procmap)
{
return close(procmap->fd);
}
+
+int write_sysfs(const char *file_path, unsigned long val)
+{
+ FILE *f = fopen(file_path, "w");
+
+ if (!f) {
+ fprintf(stderr, "f %s\n", file_path);
+ perror("fopen");
+ return 1;
+ }
+ if (fprintf(f, "%lu", val) < 0) {
+ perror("fprintf");
+ fclose(f);
+ return 1;
+ }
+ fclose(f);
+
+ return 0;
+}
+
+int read_sysfs(const char *file_path, unsigned long *val)
+{
+ FILE *f = fopen(file_path, "r");
+
+ if (!f) {
+ fprintf(stderr, "f %s\n", file_path);
+ perror("fopen");
+ return 1;
+ }
+ if (fscanf(f, "%lu", val) != 1) {
+ perror("fscanf");
+ fclose(f);
+ return 1;
+ }
+ fclose(f);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index 9211ba640d9c..f84c7c4680ea 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -87,6 +87,8 @@ int open_procmap(pid_t pid, struct procmap_fd *procmap_out);
int query_procmap(struct procmap_fd *procmap);
bool find_vma_procmap(struct procmap_fd *procmap, void *address);
int close_procmap(struct procmap_fd *procmap);
+int write_sysfs(const char *file_path, unsigned long val);
+int read_sysfs(const char *file_path, unsigned long *val);
static inline int open_self_procmap(struct procmap_fd *procmap_out)
{
--
2.34.1