Commit 2a3a2533 authored by Costa Shulyupin's avatar Costa Shulyupin Committed by Tomas Glozar
Browse files

tools/rtla: Deduplicate cgroup path opening code 



Both set_pid_cgroup() and set_comm_cgroup() functions contain
identical code for opening the cgroup.procs file.

Extract this common code into a new helper function open_cgroup_procs()
to reduce code duplication and improve maintainability.

Signed-off-by: default avatarCosta Shulyupin <costa.shul@redhat.com>
Link: https://lore.kernel.org/r/20251224125058.1771519-1-costa.shul@redhat.com


Signed-off-by: default avatarTomas Glozar <tglozar@redhat.com>
parent 0576be46

tools/tracing/rtla/src/utils.c

+32 −33
Original line number Diff line number Diff line
@@ -784,27 +784,27 @@ static int get_self_cgroup(char *self_cg, int sizeof_self_cg) 
}



/*

 * set_comm_cgroup - Set cgroup to pid_t pid

 * open_cgroup_procs - Open the cgroup.procs file for the given cgroup

 *

 * If cgroup argument is not NULL, the threads will move to the given cgroup.

 * Otherwise, the cgroup of the calling, i.e., rtla, thread will be used.

 * If cgroup argument is not NULL, the cgroup.procs file for that cgroup

 * will be opened. Otherwise, the cgroup of the calling, i.e., rtla, thread

 * will be used.

 *

 * Supports cgroup v2.

 *

 * Returns 1 on success, 0 otherwise.

 * Returns the file descriptor on success, -1 otherwise.

 */

int set_pid_cgroup(pid_t pid, const char *cgroup)

static int open_cgroup_procs(const char *cgroup)

{

	char cgroup_path[MAX_PATH - strlen("/cgroup.procs")];

	char cgroup_procs[MAX_PATH];

	char pid_str[24];

	int retval;

	int cg_fd;



	retval = find_mount("cgroup2", cgroup_path, sizeof(cgroup_path));

	if (!retval) {

		err_msg("Did not find cgroupv2 mount point\n");

		return 0;

		return -1;

	}



	if (!cgroup) {
@@ -812,7 +812,7 @@ int set_pid_cgroup(pid_t pid, const char *cgroup) 
				sizeof(cgroup_path) - strlen(cgroup_path));

		if (!retval) {

			err_msg("Did not find self cgroup\n");

			return 0;

			return -1;

		}

	} else {

		snprintf(&cgroup_path[strlen(cgroup_path)],
@@ -824,6 +824,29 @@ int set_pid_cgroup(pid_t pid, const char *cgroup) 
	debug_msg("Using cgroup path at: %s\n", cgroup_procs);



	cg_fd = open(cgroup_procs, O_RDWR);

	if (cg_fd < 0)

		return -1;



	return cg_fd;

}



/*

 * set_pid_cgroup - Set cgroup to pid_t pid

 *

 * If cgroup argument is not NULL, the threads will move to the given cgroup.

 * Otherwise, the cgroup of the calling, i.e., rtla, thread will be used.

 *

 * Supports cgroup v2.

 *

 * Returns 1 on success, 0 otherwise.

 */

int set_pid_cgroup(pid_t pid, const char *cgroup)

{

	char pid_str[24];

	int retval;

	int cg_fd;



	cg_fd = open_cgroup_procs(cgroup);

	if (cg_fd < 0)

		return 0;
@@ -853,8 +876,6 @@ int set_pid_cgroup(pid_t pid, const char *cgroup) 
 */

int set_comm_cgroup(const char *comm_prefix, const char *cgroup)

{

	char cgroup_path[MAX_PATH - strlen("/cgroup.procs")];

	char cgroup_procs[MAX_PATH];

	struct dirent *proc_entry;

	DIR *procfs;

	int retval;
@@ -866,29 +887,7 @@ int set_comm_cgroup(const char *comm_prefix, const char *cgroup) 
		return 0;

	}



	retval = find_mount("cgroup2", cgroup_path, sizeof(cgroup_path));

	if (!retval) {

		err_msg("Did not find cgroupv2 mount point\n");

		return 0;

	}



	if (!cgroup) {

		retval = get_self_cgroup(&cgroup_path[strlen(cgroup_path)],

				sizeof(cgroup_path) - strlen(cgroup_path));

		if (!retval) {

			err_msg("Did not find self cgroup\n");

			return 0;

		}

	} else {

		snprintf(&cgroup_path[strlen(cgroup_path)],

				sizeof(cgroup_path) - strlen(cgroup_path), "%s/", cgroup);

	}



	snprintf(cgroup_procs, MAX_PATH, "%s/cgroup.procs", cgroup_path);



	debug_msg("Using cgroup path at: %s\n", cgroup_procs);



	cg_fd = open(cgroup_procs, O_RDWR);

	cg_fd = open_cgroup_procs(cgroup);

	if (cg_fd < 0)

		return 0;