diff --git a/libprocessgroup/include/processgroup/processgroup.h b/libprocessgroup/include/processgroup/processgroup.h
index 8f4c764..c20586d 100644
--- a/libprocessgroup/include/processgroup/processgroup.h
+++ b/libprocessgroup/include/processgroup/processgroup.h
@@ -67,25 +67,25 @@
 
 // Return 0 if all processes were killed and the cgroup was successfully removed.
 // Returns -1 in the case of an error occurring or if there are processes still running.
-int killProcessGroup(uid_t uid, int initialPid, int signal);
+int killProcessGroup(uid_t uid, pid_t initialPid, int signal);
 
 // Returns the same as killProcessGroup(), however it does not retry, which means
 // that it only returns 0 in the case that the cgroup exists and it contains no processes.
-int killProcessGroupOnce(uid_t uid, int initialPid, int signal);
+int killProcessGroupOnce(uid_t uid, pid_t initialPid, int signal);
 
 // Sends the provided signal to all members of a process group, but does not wait for processes to
 // exit, or for the cgroup to be removed. Callers should also ensure that killProcessGroup is called
 // later to ensure the cgroup is fully removed, otherwise system resources will leak.
 // Returns true if no errors are encountered sending signals, otherwise false.
-bool sendSignalToProcessGroup(uid_t uid, int initialPid, int signal);
+bool sendSignalToProcessGroup(uid_t uid, pid_t initialPid, int signal);
 
-int createProcessGroup(uid_t uid, int initialPid, bool memControl = false);
+int createProcessGroup(uid_t uid, pid_t initialPid, bool memControl = false);
 
 // Set various properties of a process group. For these functions to work, the process group must
 // have been created by passing memControl=true to createProcessGroup.
-bool setProcessGroupSwappiness(uid_t uid, int initialPid, int swappiness);
-bool setProcessGroupSoftLimit(uid_t uid, int initialPid, int64_t softLimitInBytes);
-bool setProcessGroupLimit(uid_t uid, int initialPid, int64_t limitInBytes);
+bool setProcessGroupSwappiness(uid_t uid, pid_t initialPid, int swappiness);
+bool setProcessGroupSoftLimit(uid_t uid, pid_t initialPid, int64_t softLimitInBytes);
+bool setProcessGroupLimit(uid_t uid, pid_t initialPid, int64_t limitInBytes);
 
 void removeAllEmptyProcessGroups(void);
 
@@ -95,7 +95,7 @@
 
 // Check if a profile can be applied without failing.
 // Returns true if it can be applied without failing, false otherwise
-bool isProfileValidForProcess(const std::string& profile_name, uid_t uid, int pid);
+bool isProfileValidForProcess(const std::string& profile_name, uid_t uid, pid_t pid);
 
 #endif // __ANDROID_VNDK__
 
diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 42d415a..facfb5e 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -82,7 +82,7 @@
     return StringPrintf("%s/uid_%u", cgroup, uid);
 }
 
-static std::string ConvertUidPidToPath(const char* cgroup, uid_t uid, int pid) {
+static std::string ConvertUidPidToPath(const char* cgroup, uid_t uid, pid_t pid) {
     return StringPrintf("%s/uid_%u/pid_%d", cgroup, uid, pid);
 }
 
@@ -232,7 +232,7 @@
                                                        false);
 }
 
-static int RemoveCgroup(const char* cgroup, uid_t uid, int pid) {
+static int RemoveCgroup(const char* cgroup, uid_t uid, pid_t pid) {
     auto path = ConvertUidPidToPath(cgroup, uid, pid);
     int ret = TEMP_FAILURE_RETRY(rmdir(path.c_str()));
 
@@ -370,7 +370,7 @@
     return false;
 }
 
-bool sendSignalToProcessGroup(uid_t uid, int initialPid, int signal) {
+bool sendSignalToProcessGroup(uid_t uid, pid_t initialPid, int signal) {
     std::set<pid_t> pgids, pids;
 
     if (CgroupsAvailable()) {
@@ -525,7 +525,7 @@
 // implementation of this function. The default retry value was 40 for killing and 400 for cgroup
 // removal with 5ms sleeps between each retry.
 static int KillProcessGroup(
-        uid_t uid, int initialPid, int signal, bool once = false,
+        uid_t uid, pid_t initialPid, int signal, bool once = false,
         std::chrono::steady_clock::time_point until = std::chrono::steady_clock::now() + 2200ms) {
     CHECK_GE(uid, 0);
     CHECK_GT(initialPid, 0);
@@ -632,15 +632,15 @@
     return ret;
 }
 
-int killProcessGroup(uid_t uid, int initialPid, int signal) {
+int killProcessGroup(uid_t uid, pid_t initialPid, int signal) {
     return KillProcessGroup(uid, initialPid, signal);
 }
 
-int killProcessGroupOnce(uid_t uid, int initialPid, int signal) {
+int killProcessGroupOnce(uid_t uid, pid_t initialPid, int signal) {
     return KillProcessGroup(uid, initialPid, signal, true);
 }
 
-static int createProcessGroupInternal(uid_t uid, int initialPid, std::string cgroup,
+static int createProcessGroupInternal(uid_t uid, pid_t initialPid, std::string cgroup,
                                       bool activate_controllers) {
     auto uid_path = ConvertUidToPath(cgroup.c_str(), uid);
 
@@ -687,7 +687,7 @@
     return ret;
 }
 
-int createProcessGroup(uid_t uid, int initialPid, bool memControl) {
+int createProcessGroup(uid_t uid, pid_t initialPid, bool memControl) {
     CHECK_GE(uid, 0);
     CHECK_GT(initialPid, 0);
 
@@ -731,15 +731,15 @@
     return true;
 }
 
-bool setProcessGroupSwappiness(uid_t, int pid, int swappiness) {
+bool setProcessGroupSwappiness(uid_t, pid_t pid, int swappiness) {
     return SetProcessGroupValue(pid, "MemSwappiness", swappiness);
 }
 
-bool setProcessGroupSoftLimit(uid_t, int pid, int64_t soft_limit_in_bytes) {
+bool setProcessGroupSoftLimit(uid_t, pid_t pid, int64_t soft_limit_in_bytes) {
     return SetProcessGroupValue(pid, "MemSoftLimit", soft_limit_in_bytes);
 }
 
-bool setProcessGroupLimit(uid_t, int pid, int64_t limit_in_bytes) {
+bool setProcessGroupLimit(uid_t, pid_t pid, int64_t limit_in_bytes) {
     return SetProcessGroupValue(pid, "MemLimit", limit_in_bytes);
 }
 
@@ -747,7 +747,7 @@
     return CgroupGetAttributePathForTask(attr_name, tid, path);
 }
 
-bool isProfileValidForProcess(const std::string& profile_name, uid_t uid, int pid) {
+bool isProfileValidForProcess(const std::string& profile_name, uid_t uid, pid_t pid) {
     const TaskProfile* tp = TaskProfiles::GetInstance().GetProfile(profile_name);
 
     if (tp == nullptr) {
diff --git a/libprocessgroup/task_profiles.cpp b/libprocessgroup/task_profiles.cpp
index eaafa5e..05927cb 100644
--- a/libprocessgroup/task_profiles.cpp
+++ b/libprocessgroup/task_profiles.cpp
@@ -489,7 +489,7 @@
 }
 
 bool WriteFileAction::WriteValueToFile(const std::string& value_, ResourceCacheType cache_type,
-                                       uid_t uid, int pid, bool logfailures) const {
+                                       uid_t uid, pid_t pid, bool logfailures) const {
     std::string value(value_);
 
     value = StringReplace(value, "<uid>", std::to_string(uid), true);
@@ -564,7 +564,7 @@
     DIR* d;
     struct dirent* de;
     char proc_path[255];
-    int t_pid;
+    pid_t t_pid;
 
     sprintf(proc_path, "/proc/%d/task", pid);
     if (!(d = opendir(proc_path))) {
diff --git a/libprocessgroup/task_profiles.h b/libprocessgroup/task_profiles.h
index 25e3a02..a6ce936 100644
--- a/libprocessgroup/task_profiles.h
+++ b/libprocessgroup/task_profiles.h
@@ -185,7 +185,7 @@
     mutable std::mutex fd_mutex_;
 
     bool WriteValueToFile(const std::string& value, ResourceCacheType cache_type, uid_t uid,
-                          int pid, bool logfailures) const;
+                          pid_t pid, bool logfailures) const;
     CacheUseResult UseCachedFd(ResourceCacheType cache_type, const std::string& value) const;
 };