wait4(): retrieve dead team entries usage information.

* This adds a parameter to the wait_for_child syscall. I extended the test case
to show the actual retrieved information.
* fix #13546

headers/private/kernel/team.h

@@ -69,7 +69,8 @@ thread_id _user_load_image(const char* const* flatArgs, size_t flatArgsSize,
 status_t _user_wait_for_team(team_id id, status_t *_returnCode);
 void _user_exit_team(status_t returnValue);
 status_t _user_kill_team(thread_id thread);
-pid_t _user_wait_for_child(thread_id child, uint32 flags, siginfo_t* info);
+pid_t _user_wait_for_child(thread_id child, uint32 flags, siginfo_t* info,
+			team_usage_info* usageInfo);
 status_t _user_exec(const char *path, const char* const* flatArgs,
 			size_t flatArgsSize, int32 argCount, int32 envCount, mode_t umask);
 thread_id _user_fork(void);

headers/private/kernel/thread_types.h

@@ -116,6 +116,8 @@ struct job_control_entry : DoublyLinkedListLinkImpl<job_control_entry> {
 	status_t			status;
 	uint16				reason;		// reason for the team's demise, one of the
 									// CLD_* values defined in <signal.h>
+	bigtime_t			user_time;
+	bigtime_t			kernel_time;
 
 	job_control_entry();
 	~job_control_entry();

headers/private/system/syscalls.h

@@ -141,7 +141,7 @@ extern status_t		_kern_kill_team(team_id team);
 extern team_id		_kern_get_current_team();
 extern status_t		_kern_wait_for_team(team_id team, status_t *_returnCode);
 extern pid_t		_kern_wait_for_child(thread_id child, uint32 flags,
-						siginfo_t* info);
+						siginfo_t* info, team_usage_info* usageInfo);
 extern status_t		_kern_exec(const char *path, const char* const* flatArgs,
 						size_t flatArgsSize, int32 argCount, int32 envCount,
 						mode_t umask);

src/libs/bsd/wait.c

@@ -12,6 +12,10 @@
 #include <sys/wait.h>
 
 
+extern pid_t _waitpid(pid_t pid, int* _status, int options,
+		team_usage_info *usage_info);
+
+
 pid_t
 wait3(int *status, int options, struct rusage *rusage)
 {
@@ -22,14 +26,10 @@ wait3(int *status, int options, struct rusage *rusage)
 pid_t
 wait4(pid_t pid, int *status, int options, struct rusage *rusage)
 {
-	pid_t waitPid = waitpid(pid, status, options);
-	if (waitPid != -1) {
-		team_usage_info info;
-		
-		// Obtain info for the process that changed state.
-		if (get_team_usage_info(waitPid, RUSAGE_SELF, &info) != B_OK)
-			return -1;
-		
+	team_usage_info info;
+	pid_t waitPid = _waitpid(pid, status, options,
+		rusage != NULL ? &info : NULL);
+	if (waitPid != -1 && rusage != NULL) {
 		rusage->ru_utime.tv_sec = info.user_time / 1000000;
 		rusage->ru_utime.tv_usec = info.user_time % 1000000;
 

src/system/kernel/team.cpp

@@ -2369,6 +2369,10 @@ job_control_entry::InitDeadState()
 		reason = team->exit.reason;
 		signal = team->exit.signal;
 		signaling_user = team->exit.signaling_user;
+		user_time = team->dead_threads_user_time
+			+ team->dead_children.user_time;
+		kernel_time = team->dead_threads_kernel_time
+			+ team->dead_children.kernel_time;
 
 		team = NULL;
 	}
@@ -2387,6 +2391,8 @@ job_control_entry::operator=(const job_control_entry& other)
 	group_id = other.group_id;
 	status = other.status;
 	reason = other.reason;
+	user_time = other.user_time;
+	kernel_time = other.kernel_time;
 
 	return *this;
 }
@@ -2395,7 +2401,8 @@ job_control_entry::operator=(const job_control_entry& other)
 /*! This is the kernel backend for waitid().
 */
 static thread_id
-wait_for_child(pid_t child, uint32 flags, siginfo_t& _info)
+wait_for_child(pid_t child, uint32 flags, siginfo_t& _info,
+	team_usage_info& _usage_info)
 {
 	Thread* thread = thread_get_current_thread();
 	Team* team = thread->team;
@@ -2533,6 +2540,8 @@ wait_for_child(pid_t child, uint32 flags, siginfo_t& _info)
 			_info.si_code = foundEntry.reason;
 			_info.si_status = foundEntry.reason == CLD_EXITED
 				? foundEntry.status : foundEntry.signal;
+			_usage_info.user_time = foundEntry.user_time;
+			_usage_info.kernel_time = foundEntry.kernel_time;
 			break;
 		case JOB_CONTROL_STATE_STOPPED:
 			_info.si_code = CLD_STOPPED;
@@ -3915,19 +3924,28 @@ _user_fork(void)
 
 
 pid_t
-_user_wait_for_child(thread_id child, uint32 flags, siginfo_t* userInfo)
+_user_wait_for_child(thread_id child, uint32 flags, siginfo_t* userInfo,
+	team_usage_info* usageInfo)
 {
 	if (userInfo != NULL && !IS_USER_ADDRESS(userInfo))
 		return B_BAD_ADDRESS;
+	if (usageInfo != NULL && !IS_USER_ADDRESS(usageInfo))
+		return B_BAD_ADDRESS;
 
 	siginfo_t info;
-	pid_t foundChild = wait_for_child(child, flags, info);
+	team_usage_info usage_info;
+	pid_t foundChild = wait_for_child(child, flags, info, usage_info);
 	if (foundChild < 0)
 		return syscall_restart_handle_post(foundChild);
 
 	// copy info back to userland
 	if (userInfo != NULL && user_memcpy(userInfo, &info, sizeof(info)) != B_OK)
 		return B_BAD_ADDRESS;
+	// copy usage_info back to userland
+	if (usageInfo != NULL && user_memcpy(usageInfo, &usage_info,
+		sizeof(usage_info)) != B_OK) {
+		return B_BAD_ADDRESS;
+	}
 
 	return foundChild;
 }

src/system/libroot/posix/sys/wait.cpp

@@ -23,13 +23,12 @@ wait(int* _status)
 	return waitpid(-1, _status, 0);
 }
 
-
-pid_t
-waitpid(pid_t pid, int* _status, int options)
+extern "C" pid_t
+_waitpid(pid_t pid, int* _status, int options, team_usage_info *usage_info)
 {
 	// wait
 	siginfo_t info;
-	pid_t child = _kern_wait_for_child(pid, options, &info);
+	pid_t child = _kern_wait_for_child(pid, options, &info, usage_info);
 
 	pthread_testcancel();
 
@@ -84,6 +83,13 @@ waitpid(pid_t pid, int* _status, int options)
 }
 
 
+pid_t
+waitpid(pid_t pid, int* _status, int options)
+{
+	return _waitpid(pid, _status, options, NULL);
+}
+
+
 int
 waitid(idtype_t idType, id_t id, siginfo_t* info, int options)
 {
@@ -111,7 +117,7 @@ waitid(idtype_t idType, id_t id, siginfo_t* info, int options)
 			RETURN_AND_SET_ERRNO_TEST_CANCEL(EINVAL);
 	}
 
-	pid_t child = _kern_wait_for_child(id, options, info);
+	pid_t child = _kern_wait_for_child(id, options, info, NULL);
 	if (child >= 0 || child == B_WOULD_BLOCK)
 		return 0;
 

src/tests/libs/bsd/wait4_test.cpp

@@ -5,6 +5,7 @@
 
 
 #include <errno.h>
+#include <inttypes.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/resource.h> 
@@ -55,10 +56,14 @@ main(int argc, char** argv)
 	struct rusage usage;
 	pid_t pid;
 	do {
+		memset(&usage, 0, sizeof(usage));
 		int childStatus = -1;
 		pid = wait4(-1, &childStatus, 0, &usage);
-		printf("wait4() returned %ld (%s), child status %d\n",
-			pid, strerror(errno), childStatus);
+		printf("wait4() returned %" PRId32 " (%s), child status %" PRId32
+			", kernel: %ld.%06" PRId32 " user: %ld.%06" PRId32 "\n",
+			pid, strerror(errno), childStatus, usage.ru_stime.tv_sec,
+			usage.ru_stime.tv_usec, usage.ru_utime.tv_sec,
+			usage.ru_utime.tv_usec);
 	} while (pid >= 0);
 
 	return 0;