@@ -112,7 +112,9 @@ struct tst_cgroup_group;
void tst_cgroup_scan(void);
/* Print the config detected by tst_cgroup_scan */
void tst_cgroup_print_config(void);
-
+/* Load the config printed by tst_cgroup_print_config() to update the
+ * the internal state of the test to the given config */
+void tst_cgroup_load_config(const char *const config);
/* Ensure the specified controller is available in the test's default
* CGroup, mounting/enabling it if necessary */
void tst_cgroup_require(const char *const ctrl_name,
@@ -375,6 +375,112 @@ static struct cgroup_root *cgroup_find_root(const char *const mnt_path)
return NULL;
}
+static int parse_ctrl_config(const char *const config_entry)
+{
+ char *token;
+ struct cgroup_ctrl *ctrl = NULL;
+
+ if (!strcmp(CONFIG_CTRL_HEADER, config_entry))
+ return 0;
+
+ if (!strcmp(CONFIG_ROOT_HEADER, config_entry))
+ return 1;
+
+ for (token = strtok(config_entry, " "); token; token = strtok(NULL, " ")) {
+ if (!ctrl && !(ctrl = cgroup_find_ctrl(token)))
+ tst_brk(TBROK, "Could not find ctrl from config. Ctrls changing between calls?");
+
+ if (ctrl && !strcmp(token, CONFIG_CTRL_REQUIRED))
+ ctrl->we_require_it = 1;
+ }
+
+ return 0;
+}
+
+static int parse_root_config(char *config_entry)
+{
+ char *key;
+ char *value;
+ struct cgroup_root *root = NULL;
+
+ for (key = strtok(config_entry, " "); key; key = strtok(NULL, " ")) {
+ if (!(value = strchr(key, '='))) {
+ if (!(root = cgroup_find_root(key)))
+ tst_brk(TBROK, "Could not find root from config. Roots changing between calls?");
+
+ continue;
+ }
+
+ if (!root)
+ tst_brk(TBROK, "Root has not been found, possibly malformed config?");
+
+ *value = '\0';
+ value = value + 1;
+
+ if (!strcmp(key, CONFIG_MOUNTROOT_KEY) && !strcmp(value, "yes")) {
+ root->we_mounted_it = 1;
+ } else if (!strcmp(key, CONFIG_LTPDIR_KEY) && !root->ltp_dir.dir_name) {
+ cgroup_dir_mk(&root->mnt_dir, cgroup_ltp_dir, &root->ltp_dir);
+ cgroup_dir_mk(&root->ltp_dir, cgroup_ltp_drain_dir, &root->drain_dir);
+ if (!strcmp(value, "yes")) {
+ root->ltp_dir.we_created_it = 1;
+ root->drain_dir.we_created_it = 1;
+ }
+ } else if (!strcmp(key, CONFIG_TESTID_KEY) && strcmp(value, "NULL") &&
+ !root->test_dir.dir_name) {
+ cgroup_dir_mk(&root->ltp_dir, value, &root->test_dir);
+ root->test_dir.we_created_it = 1;
+ }
+ }
+
+ return 0;
+}
+
+/* Load the test state configuration provided by tst_cgroup_print_config()
+ *
+ * This will reload some internal tst_cgroup state given by the config
+ * that might otherwise have been lost between calls or between different
+ * processes. In particular this is used by testcases/lib/tst_cgctl to
+ * provide access to this C api to shell scripts.
+ *
+ * The config keeps track of the minimal state needed for tst_cgroup_cleanup
+ * to cleanup after a test and does not keep track of the creation of
+ * test cgroups that might be created through tst_cgroup_group_mk().
+ */
+void tst_cgroup_load_config(const char *const config)
+{
+ char temp_config[BUFSIZ];
+ char *curr_line;
+ char *next_line;
+
+ if (strlen(config) >= BUFSIZ)
+ tst_brk(TBROK, "Config has exceeded buffer size?");
+
+ strncpy(temp_config, config, BUFSIZ);
+
+ for (curr_line = &temp_config[0]; curr_line; curr_line = next_line + 1) {
+ next_line = strchr(curr_line, '\n');
+ if (next_line)
+ *next_line = '\0';
+
+ if (parse_ctrl_config(curr_line))
+ break;
+ }
+
+ for (curr_line = next_line + 1; curr_line; curr_line = next_line + 1) {
+ next_line = strchr(curr_line, '\n');
+ if (next_line)
+ *next_line = '\0';
+
+ parse_root_config(curr_line);
+ /* Bash will truncate the last newline that we are using to deliminate
+ * the start and end of valid entries, so if we could not detect any more
+ * newlines we assume that was our last entry. */
+ if (!next_line)
+ break;
+ }
+}
+
/* Determine if a mounted cgroup hierarchy is unique and record it if so.
*
* For CGroups V2 this is very simple as there is only one
Implement tst_cgroup_load_config which consumes the state given by tst_cgroup_print_config() to update the internal test state to reflect the given config. This allows for programs using the cgroup C API to load and reload state, allowing functionality such as calling tst_cgroup_require and tst_cgroup_cleanup to function properly between programs or between invocations of a binary using the C API. Signed-off-by: Luke Nowakowski-Krijger <luke.nowakowskikrijger@canonical.com> --- v2: Add root null check in parse_root_config. Remove checking for ltp_drain_dir key from config as it was redundant. Remove unsued variable in parse_ctrl_config. Cleanup some compiler warnings. include/tst_cgroup.h | 4 +- lib/tst_cgroup.c | 106 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 109 insertions(+), 1 deletion(-)