xref: /linux/tools/testing/selftests/cgroup/lib/include/cgroup_util.h (revision 311ead1be05d2348e89f873337c8375e856e1abb)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <stdbool.h>
3 #include <stdlib.h>
4 
5 #ifndef PAGE_SIZE
6 #define PAGE_SIZE 4096
7 #endif
8 
9 #define MB(x) (x << 20)
10 
11 #define USEC_PER_SEC	1000000L
12 #define NSEC_PER_SEC	1000000000L
13 
14 #define TEST_UID	65534 /* usually nobody, any !root is fine */
15 
16 #define CG_THREADS_FILE (!cg_test_v1_named ? "cgroup.threads" : "tasks")
17 #define CG_NAMED_NAME "selftest"
18 #define CG_PATH_FORMAT (!cg_test_v1_named ? "0::%s" : (":name=" CG_NAMED_NAME ":%s"))
19 
20 #define DEFAULT_WAIT_INTERVAL_US (100 * 1000) /* 100 ms */
21 
22 /*
23  * Checks if two given values differ by less than err% of their sum.
24  */
25 static inline int values_close(long a, long b, int err)
26 {
27 	return labs(a - b) <= (a + b) / 100 * err;
28 }
29 
30 /*
31  * Checks if two given values differ by less than err% of their sum and assert
32  * with detailed debug info if not.
33  */
34 static inline int values_close_report(long a, long b, int err)
35 {
36 	long diff  = labs(a - b);
37 	long limit = (a + b) / 100 * err;
38 	double actual_err = (a + b) ? (100.0 * diff / (a + b)) : 0.0;
39 	int close = diff <= limit;
40 
41 	if (!close)
42 		fprintf(stderr,
43 			"[FAIL] actual=%ld expected=%ld | diff=%ld | limit=%ld | "
44 			"tolerance=%d%% | actual_error=%.2f%%\n",
45 			a, b, diff, limit, err, actual_err);
46 
47 	return close;
48 }
49 
50 extern ssize_t read_text(const char *path, char *buf, size_t max_len);
51 extern ssize_t write_text(const char *path, char *buf, ssize_t len);
52 
53 extern int cg_find_controller_root(char *root, size_t len, const char *controller);
54 extern int cg_find_unified_root(char *root, size_t len, bool *nsdelegate);
55 extern char *cg_name(const char *root, const char *name);
56 extern char *cg_name_indexed(const char *root, const char *name, int index);
57 extern char *cg_control(const char *cgroup, const char *control);
58 extern int cg_create(const char *cgroup);
59 extern int cg_destroy(const char *cgroup);
60 extern int cg_read(const char *cgroup, const char *control,
61 		   char *buf, size_t len);
62 extern int cg_read_strcmp(const char *cgroup, const char *control,
63 			  const char *expected);
64 extern int cg_read_strstr(const char *cgroup, const char *control,
65 			  const char *needle);
66 extern long cg_read_long(const char *cgroup, const char *control);
67 extern long cg_read_long_fd(int fd);
68 long cg_read_key_long(const char *cgroup, const char *control, const char *key);
69 long cg_read_key_long_poll(const char *cgroup, const char *control,
70 			   const char *key, long expected, int retries,
71 			   useconds_t wait_interval_us);
72 extern long cg_read_lc(const char *cgroup, const char *control);
73 extern int cg_write(const char *cgroup, const char *control, char *buf);
74 extern int cg_open(const char *cgroup, const char *control, int flags);
75 int cg_write_numeric(const char *cgroup, const char *control, long value);
76 extern int cg_run(const char *cgroup,
77 		  int (*fn)(const char *cgroup, void *arg),
78 		  void *arg);
79 extern int cg_enter(const char *cgroup, int pid);
80 extern int cg_enter_current(const char *cgroup);
81 extern int cg_enter_current_thread(const char *cgroup);
82 extern int cg_run_nowait(const char *cgroup,
83 			 int (*fn)(const char *cgroup, void *arg),
84 			 void *arg);
85 extern int cg_wait_for_proc_count(const char *cgroup, int count);
86 extern int cg_killall(const char *cgroup);
87 int proc_mount_contains(const char *option);
88 int cgroup_feature(const char *feature);
89 extern ssize_t proc_read_text(int pid, bool thread, const char *item, char *buf, size_t size);
90 extern int proc_read_strstr(int pid, bool thread, const char *item, const char *needle);
91 extern pid_t clone_into_cgroup(int cgroup_fd);
92 extern int clone_reap(pid_t pid, int options);
93 extern int clone_into_cgroup_run_wait(const char *cgroup);
94 extern int dirfd_open_opath(const char *dir);
95 extern int cg_prepare_for_wait(const char *cgroup);
96 extern int memcg_prepare_for_wait(const char *cgroup);
97 extern int cg_wait_for(int fd);
98 extern bool cg_test_v1_named;
99