diff options
| -rw-r--r-- | lib/igt_aux.c | 134 | ||||
| -rw-r--r-- | lib/igt_aux.h | 4 |
2 files changed, 138 insertions, 0 deletions
diff --git a/lib/igt_aux.c b/lib/igt_aux.c index d5c70fa2..5392e1a1 100644 --- a/lib/igt_aux.c +++ b/lib/igt_aux.c @@ -735,3 +735,137 @@ void igt_unlock_mem(void) free(locked_mem); locked_mem = NULL; } + + +#define MODULE_PARAM_DIR "/sys/module/i915/parameters/" +#define PARAM_NAME_MAX_SZ 32 +#define PARAM_VALUE_MAX_SZ 16 +#define PARAM_FILE_PATH_MAX_SZ (strlen(MODULE_PARAM_DIR) + PARAM_NAME_MAX_SZ) + +struct module_param_data { + char name[PARAM_NAME_MAX_SZ]; + char original_value[PARAM_VALUE_MAX_SZ]; + + struct module_param_data *next; +}; +struct module_param_data *module_params = NULL; + +static void igt_module_param_exit_handler(int sig) +{ + const size_t dir_len = strlen(MODULE_PARAM_DIR); + char file_path[PARAM_FILE_PATH_MAX_SZ]; + struct module_param_data *data; + int fd; + + /* We don't need to assert string sizes on this function since they were + * already checked before being stored on the lists. Besides, + * igt_assert() is not AS-Safe. */ + strcpy(file_path, MODULE_PARAM_DIR); + + for (data = module_params; data != NULL; data = data->next) { + strcpy(file_path + dir_len, data->name); + + fd = open(file_path, O_RDWR); + if (fd >= 0) { + write(fd, data->original_value, + strlen(data->original_value)); + close(fd); + } + } + /* free() is not AS-Safe, so we can't call it here. */ +} + +/** + * igt_save_module_param: + * @name: name of the i915.ko module parameter + * @file_path: full sysfs file path for the parameter + * + * Reads the current value of an i915.ko module parameter, saves it on an array, + * then installs an exit handler to restore it when the program exits. + * + * It is safe to call this function multiple times for the same parameter. + * + * Notice that this function is called by igt_set_module_param(), so that one - + * or one of its wrappers - is the only function the test programs need to call. + */ +static void igt_save_module_param(const char *name, const char *file_path) +{ + struct module_param_data *data; + size_t n; + int fd; + + /* Check if this parameter is already saved. */ + for (data = module_params; data != NULL; data = data->next) + if (strncmp(data->name, name, PARAM_NAME_MAX_SZ) == 0) + return; + + if (!module_params) + igt_install_exit_handler(igt_module_param_exit_handler); + + data = calloc(1, sizeof (*data)); + igt_assert(data); + + strncpy(data->name, name, PARAM_NAME_MAX_SZ); + + fd = open(file_path, O_RDONLY); + igt_assert(fd >= 0); + + n = read(fd, data->original_value, PARAM_VALUE_MAX_SZ); + igt_assert_f(n > 0 && n < PARAM_VALUE_MAX_SZ, + "Need to increase PARAM_VALUE_MAX_SZ\n"); + + igt_assert(close(fd) == 0); + + data->next = module_params; + module_params = data; +} + +/** + * igt_set_module_param: + * @name: i915.ko parameter name + * @val: i915.ko parameter value + * + * This function sets the desired value for the given i915.ko parameter. It also + * takes care of saving and restoring the values that were already set before + * the test was run by calling igt_save_module_param(). + * + * Please consider using igt_set_module_param_int() for the integer and bool + * parameters. + */ +void igt_set_module_param(const char *name, const char *val) +{ + char file_path[PARAM_FILE_PATH_MAX_SZ]; + size_t len = strlen(val); + int fd; + + igt_assert_f(strlen(name) < PARAM_NAME_MAX_SZ, + "Need to increase PARAM_NAME_MAX_SZ\n"); + strcpy(file_path, MODULE_PARAM_DIR); + strcpy(file_path + strlen(MODULE_PARAM_DIR), name); + + igt_save_module_param(name, file_path); + + fd = open(file_path, O_RDWR); + igt_assert(write(fd, val, len) == len); + igt_assert(close(fd) == 0); +} + +/** + * igt_set_module_param_int: + * @name: i915.ko parameter name + * @val: i915.ko parameter value + * + * This is a wrapper for igt_set_module_param() that takes an integer instead of + * a string. Please see igt_set_module_param(). + */ +void igt_set_module_param_int(const char *name, int val) +{ + char str[PARAM_VALUE_MAX_SZ]; + int n; + + n = snprintf(str, PARAM_VALUE_MAX_SZ, "%d\n", val); + igt_assert_f(n < PARAM_VALUE_MAX_SZ, + "Need to increase PARAM_VALUE_MAX_SZ\n"); + + igt_set_module_param(name, str); +} diff --git a/lib/igt_aux.h b/lib/igt_aux.h index b2dc2679..9ea50de2 100644 --- a/lib/igt_aux.h +++ b/lib/igt_aux.h @@ -145,4 +145,8 @@ void igt_unlock_mem(void); ret_; \ }) + +void igt_set_module_param(const char *name, const char *val); +void igt_set_module_param_int(const char *name, int val); + #endif /* IGT_AUX_H */ |