diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index f7af08b..38eb92f 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -446,14 +446,9 @@
 
 static int KillProcessGroup(uid_t uid, int initialPid, int signal, int retries,
                             int* max_processes) {
-    if (uid < 0) {
-        LOG(ERROR) << __func__ << ": invalid UID " << uid;
-        return -1;
-    }
-    if (initialPid <= 0) {
-        LOG(ERROR) << __func__ << ": invalid PID " << initialPid;
-        return -1;
-    }
+    CHECK_GE(uid, 0);
+    CHECK_GT(initialPid, 0);
+
     std::string hierarchy_root_path;
     if (CgroupsAvailable()) {
         CgroupGetControllerPath(CGROUPV2_CONTROLLER_NAME, &hierarchy_root_path);
@@ -590,7 +585,8 @@
 }
 
 int createProcessGroup(uid_t uid, int initialPid, bool memControl) {
-    std::string cgroup;
+    CHECK_GE(uid, 0);
+    CHECK_GT(initialPid, 0);
 
     if (memControl && !UsePerAppMemcg()) {
         PLOG(ERROR) << "service memory controls are used without per-process memory cgroup support";
@@ -608,6 +604,7 @@
         }
     }
 
+    std::string cgroup;
     CgroupGetControllerPath(CGROUPV2_CONTROLLER_NAME, &cgroup);
     return createProcessGroupInternal(uid, initialPid, cgroup, true);
 }