Set oom_score_adj to 0 for all enroot processes

Fixes #120

Signed-off-by: Felix Abecassis <[email protected]>

enroot.c

@@ -21,6 +21,7 @@ pid_t enroot_exec(uid_t uid, gid_t gid, int log_fd,
 	int ret;
 	int null_fd = -1;
 	int target_fd = -1;
+	int oom_score_fd = -1;
 	pid_t pid;
 	char *argv_str;
 
@@ -59,6 +60,16 @@ pid_t enroot_exec(uid_t uid, gid_t gid, int log_fd,
 		if (ret < 0)
 			_exit(EXIT_FAILURE);
 
+		/*
+		 * Attempt to set oom_score_adj to 0, as it's often set to -1000 (OOM killing
+		 * disabled), inherited from slurmstepd or slurmd.
+		 */
+		oom_score_fd = open("/proc/self/oom_score_adj", O_CLOEXEC | O_WRONLY | O_APPEND);
+		if (oom_score_fd >= 0) {
+			dprintf(oom_score_fd, "%d", 0);
+			close(oom_score_fd);
+		}
+
 		ret = setregid(gid, gid);
 		if (ret < 0)
 			_exit(EXIT_FAILURE);