[igt-dev] [PATCH i-g-t 3/7] lib/params: overhaul param saving

Juha-Pekka Heikkila
2020-04-28T20:23:52Z

From: Jani Nikula <jani.nikula@intel.com>

More generic, use existing functions.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
---
lib/igt_params.c | 101 +++++++++++++++++++----------------------------
1 file changed, 41 insertions(+), 60 deletions(-)

diff --git a/lib/igt_params.c b/lib/igt_params.c
index f220e73b..b5ac1266 100644
--- a/lib/igt_params.c
+++ b/lib/igt_params.c
@@ -34,92 +34,74 @@
#include "igt_params.h"
#include "igt_sysfs.h"

-#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];
+ char *path;
+ char *name;
+ char *original_value;

struct module_param_data *next;
};
struct module_param_data *module_params = NULL;

-static void igt_module_param_exit_handler(int sig)
+static void igt_params_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);
+ int 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) {
- int size = strlen (data->original_value);
-
- if (size != write(fd, data->original_value, size)) {
- const char msg[] = "WARNING: Module parameters "
- "may not have been reset to their "
- "original values\n";
- assert(write(STDERR_FILENO, msg, sizeof(msg))
- == sizeof(msg));
- }
-
- close(fd);
+ dir = open(data->path, O_RDONLY);
+
+ if (!igt_sysfs_set(dir, data->name, data->original_value)) {
+ const char msg[] = "WARNING: Module parameters "
+ "may not have been reset to their "
+ "original values\n";
+ assert(write(STDERR_FILENO, msg, sizeof(msg))
+ == sizeof(msg));
}
+
+ close(dir);
}
/* 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
+ * igt_params_save:
+ * @dir: file handle for path
+ * @path: full path to the sysfs directory
+ * @name: name of the sysfs attribute
*
- * 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.
+ * Reads the current value of a sysfs attribute, 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)
+static void igt_params_save(int dir, const char *path, const char *name)
{
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)
+ if (strcmp(data->path, path) == 0 &&
+ strcmp(data->name, name) == 0)
return;

if (!module_params)
- igt_install_exit_handler(igt_module_param_exit_handler);
+ igt_install_exit_handler(igt_params_exit_handler);

data = calloc(1, sizeof (*data));
igt_assert(data);

- strncpy(data->name, name, PARAM_NAME_MAX_SZ - 1);
-
- fd = open(file_path, O_RDONLY);
- igt_assert(fd >= 0);
+ data->path = strdup(path);
+ igt_assert(data->path);

- 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");
+ data->name = strdup(name);
+ igt_assert(data->name);

- igt_assert(close(fd) == 0);
+ data->original_value = igt_sysfs_get(dir, name);
+ igt_assert(data->original_value);

data->next = module_params;
module_params = data;
@@ -205,22 +187,21 @@ bool igt_params_set(int device, const char *parameter, const char *fmt, ...)
*/
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;
+ const char *path = "/sys/module/i915/parameters";
+ int dir;

- 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);
+ dir = open(path, O_RDONLY);
+ igt_assert(dir >= 0);

- igt_save_module_param(name, file_path);
+ igt_params_save(dir, path, name);

- fd = open(file_path, O_RDWR);
- igt_assert(write(fd, val, len) == len);
- igt_assert(close(fd) == 0);
+ igt_assert(igt_sysfs_set(dir, name, val));
+
+ igt_assert(close(dir) == 0);
}

+#define PARAM_VALUE_MAX_SZ 16
+
/**
* igt_set_module_param_int:
* @name: i915.ko parameter name
--
2.26.0