Commit 3a7f9e51 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

cgroup: selftests: Move memcontrol specific helpers out of common cgroup_util.c 



Move a handful of helpers out of cgroup_util.c and into test_memcontrol.c
that have nothing to with cgroups in general, in anticipation of making
cgroup_util.c a generic library that can be used by other selftests.

Make read_text() and write_text() non-static so test_memcontrol.c can
use them.

Signed-off-by: default avatarJames Houghton <jthoughton@google.com>
Acked-by: default avatarMichal Koutný <mkoutny@suse.com>
Link: https://lore.kernel.org/r/20250508184649.2576210-4-jthoughton@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 26dcdfa0

tools/testing/selftests/cgroup/cgroup_util.c

+2 −80
Original line number Diff line number Diff line
@@ -20,7 +20,7 @@ 
#include "../clone3/clone3_selftests.h"



/* Returns read len on success, or -errno on failure. */

static ssize_t read_text(const char *path, char *buf, size_t max_len)

ssize_t read_text(const char *path, char *buf, size_t max_len)

{

	ssize_t len;

	int fd;
@@ -39,7 +39,7 @@ static ssize_t read_text(const char *path, char *buf, size_t max_len) 
}



/* Returns written len on success, or -errno on failure. */

static ssize_t write_text(const char *path, char *buf, ssize_t len)

ssize_t write_text(const char *path, char *buf, ssize_t len)

{

	int fd;
@@ -488,84 +488,6 @@ int cg_run_nowait(const char *cgroup, 
	return pid;

}



int get_temp_fd(void)

{

	return open(".", O_TMPFILE | O_RDWR | O_EXCL);

}



int alloc_pagecache(int fd, size_t size)

{

	char buf[PAGE_SIZE];

	struct stat st;

	int i;



	if (fstat(fd, &st))

		goto cleanup;



	size += st.st_size;



	if (ftruncate(fd, size))

		goto cleanup;



	for (i = 0; i < size; i += sizeof(buf))

		read(fd, buf, sizeof(buf));



	return 0;



cleanup:

	return -1;

}



int alloc_anon(const char *cgroup, void *arg)

{

	size_t size = (unsigned long)arg;

	char *buf, *ptr;



	buf = malloc(size);

	for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE)

		*ptr = 0;



	free(buf);

	return 0;

}



int is_swap_enabled(void)

{

	char buf[PAGE_SIZE];

	const char delim[] = "\n";

	int cnt = 0;

	char *line;



	if (read_text("/proc/swaps", buf, sizeof(buf)) <= 0)

		return -1;



	for (line = strtok(buf, delim); line; line = strtok(NULL, delim))

		cnt++;



	return cnt > 1;

}



int set_oom_adj_score(int pid, int score)

{

	char path[PATH_MAX];

	int fd, len;



	sprintf(path, "/proc/%d/oom_score_adj", pid);



	fd = open(path, O_WRONLY | O_APPEND);

	if (fd < 0)

		return fd;



	len = dprintf(fd, "%d", score);

	if (len < 0) {

		close(fd);

		return len;

	}



	close(fd);

	return 0;

}



int proc_mount_contains(const char *option)

{

	char buf[4 * PAGE_SIZE];

tools/testing/selftests/cgroup/cgroup_util.h

+3 −5
Original line number Diff line number Diff line
@@ -21,6 +21,9 @@ static inline int values_close(long a, long b, int err) 
	return labs(a - b) <= (a + b) / 100 * err;

}



extern ssize_t read_text(const char *path, char *buf, size_t max_len);

extern ssize_t write_text(const char *path, char *buf, ssize_t len);



extern int cg_find_unified_root(char *root, size_t len, bool *nsdelegate);

extern char *cg_name(const char *root, const char *name);

extern char *cg_name_indexed(const char *root, const char *name, int index);
@@ -49,11 +52,6 @@ extern int cg_enter_current_thread(const char *cgroup); 
extern int cg_run_nowait(const char *cgroup,

			 int (*fn)(const char *cgroup, void *arg),

			 void *arg);

extern int get_temp_fd(void);

extern int alloc_pagecache(int fd, size_t size);

extern int alloc_anon(const char *cgroup, void *arg);

extern int is_swap_enabled(void);

extern int set_oom_adj_score(int pid, int score);

extern int cg_wait_for_proc_count(const char *cgroup, int count);

extern int cg_killall(const char *cgroup);

int proc_mount_contains(const char *option);

tools/testing/selftests/cgroup/test_memcontrol.c

+78 −0
Original line number Diff line number Diff line
@@ -24,6 +24,84 @@ 
static bool has_localevents;

static bool has_recursiveprot;



int get_temp_fd(void)

{

	return open(".", O_TMPFILE | O_RDWR | O_EXCL);

}



int alloc_pagecache(int fd, size_t size)

{

	char buf[PAGE_SIZE];

	struct stat st;

	int i;



	if (fstat(fd, &st))

		goto cleanup;



	size += st.st_size;



	if (ftruncate(fd, size))

		goto cleanup;



	for (i = 0; i < size; i += sizeof(buf))

		read(fd, buf, sizeof(buf));



	return 0;



cleanup:

	return -1;

}



int alloc_anon(const char *cgroup, void *arg)

{

	size_t size = (unsigned long)arg;

	char *buf, *ptr;



	buf = malloc(size);

	for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE)

		*ptr = 0;



	free(buf);

	return 0;

}



int is_swap_enabled(void)

{

	char buf[PAGE_SIZE];

	const char delim[] = "\n";

	int cnt = 0;

	char *line;



	if (read_text("/proc/swaps", buf, sizeof(buf)) <= 0)

		return -1;



	for (line = strtok(buf, delim); line; line = strtok(NULL, delim))

		cnt++;



	return cnt > 1;

}



int set_oom_adj_score(int pid, int score)

{

	char path[PATH_MAX];

	int fd, len;



	sprintf(path, "/proc/%d/oom_score_adj", pid);



	fd = open(path, O_WRONLY | O_APPEND);

	if (fd < 0)

		return fd;



	len = dprintf(fd, "%d", score);

	if (len < 0) {

		close(fd);

		return len;

	}



	close(fd);

	return 0;

}



/*

 * This test creates two nested cgroups with and without enabling

 * the memory controller.