POSIX: add pthread_getcpuclockid()

fix #15615

Change-Id: I6b34f97464fac97d0b339fa338cfc5df34536080
Reviewed-on: https://review.haiku-os.org/c/haiku/+/8681
Reviewed-by: Jérôme Duval <jerome.duval@gmail.com>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>

headers/posix/pthread.h

@@ -196,6 +196,7 @@ extern int pthread_atfork(void (*prepare)(void), void (*parent)(void),
 	void (*child)(void));
 extern int pthread_once(pthread_once_t *once_control,
 	void (*init_routine)(void));
+extern int pthread_getcpuclockid(pthread_t thread_id, clockid_t* clock_id);
 
 /* thread attributes functions */
 extern int pthread_attr_destroy(pthread_attr_t *attr);

headers/private/kernel/UserTimer.h

@@ -261,6 +261,7 @@ void		user_timer_check_team_user_timers(Team* team);
 
 status_t	_user_get_clock(clockid_t clockID, bigtime_t* _time);
 status_t	_user_set_clock(clockid_t clockID, bigtime_t time);
+status_t	_user_get_cpuclockid(thread_id id, int32 which, clockid_t* _clockID);
 
 int32		_user_create_timer(clockid_t clockID, thread_id threadID,
 				uint32 flags, const struct sigevent* event,

headers/private/system/syscall_clock_info.h

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2024, Jérôme Duval, jerome.duval@gmail.com. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef _SYSTEM_SYSCALL_CLOCK_INFO_H
+#define _SYSTEM_SYSCALL_CLOCK_INFO_H
+
+
+enum which_process_info {
+	TEAM_ID = 1,
+	THREAD_ID,
+};
+
+
+#endif	/* _SYSTEM_SYSCALL_CLOCK_INFO_H */

headers/private/system/syscalls.h

@@ -412,6 +412,7 @@ extern status_t		_kern_get_real_time_clock_is_gmt(bool *_isGMT);
 
 extern status_t		_kern_get_clock(clockid_t clockID, bigtime_t* _time);
 extern status_t		_kern_set_clock(clockid_t clockID, bigtime_t time);
+extern status_t		_kern_get_cpuclockid(thread_id id, int32 which, clockid_t* _clockID);
 
 extern bigtime_t	_kern_system_time();
 extern status_t		_kern_snooze_etc(bigtime_t time, int timebase, int32 flags,

src/system/kernel/UserTimer.cpp

@@ -14,12 +14,19 @@
 #include <debug.h>
 #include <kernel.h>
 #include <real_time_clock.h>
+#include <syscall_clock_info.h>
 #include <team.h>
 #include <thread_types.h>
 #include <UserEvent.h>
 #include <util/AutoLock.h>
 
 
+#define CPUCLOCK_TEAM		0x00000000
+#define CPUCLOCK_THREAD		0x80000000
+#define CPUCLOCK_SPECIAL	0xc0000000
+#define CPUCLOCK_ID_MASK	(~(CPUCLOCK_SPECIAL))
+
+
 // Minimum interval length in microseconds for a periodic timer. This is not a
 // restriction on the user timer interval length itself, but the minimum time
 // span by which we advance the start time for kernel timers. A shorted user
@@ -1505,13 +1512,24 @@ user_timer_get_clock(clockid_t clockID, bigtime_t& _time)
 			team_id teamID;
 			if (clockID == CLOCK_PROCESS_CPUTIME_ID) {
 				teamID = B_CURRENT_TEAM;
-			} else {
+			} else if ((clockID & CPUCLOCK_THREAD) == CPUCLOCK_THREAD) {
-				if (clockID < 0)
+				thread_id threadID = clockID & CPUCLOCK_ID_MASK;
+				// get the thread
+				Thread* thread = Thread::Get(threadID);
+				if (thread == NULL)
 					return B_BAD_VALUE;
-				if (clockID == team_get_kernel_team_id())
+				BReference<Thread> threadReference(thread, true);
+				if (thread->team == team_get_kernel_team())
 					return B_NOT_ALLOWED;
+				// get the time
+				InterruptsSpinLocker timeLocker(thread->time_lock);
+				_time = thread->CPUTime(false);
 
-				teamID = clockID;
+				return B_OK;
+			} else if ((clockID & CPUCLOCK_TEAM) == CPUCLOCK_TEAM) {
+				teamID = clockID & CPUCLOCK_ID_MASK;
+				if (teamID == team_get_kernel_team_id())
+					return B_NOT_ALLOWED;
 			}
 
 			// get the team
@@ -1657,13 +1675,31 @@ _user_set_clock(clockid_t clockID, bigtime_t time)
 			team_id teamID;
 			if (clockID == CLOCK_PROCESS_CPUTIME_ID) {
 				teamID = B_CURRENT_TEAM;
-			} else {
+			} else if ((clockID & CPUCLOCK_THREAD) != 0) {
-				if (clockID < 0)
+				thread_id threadID = clockID & CPUCLOCK_ID_MASK;
+				if (threadID < 0)
 					return B_BAD_VALUE;
-				if (clockID == team_get_kernel_team_id())
+				// get the thread
+				Thread* thread = Thread::Get(threadID);
+				if (thread == NULL)
+					return B_BAD_VALUE;
+				BReference<Thread> threadReference(thread, true);
+				if (thread->team == team_get_kernel_team())
 					return B_NOT_ALLOWED;
 
-				teamID = clockID;
+				// set the time offset
+				InterruptsSpinLocker timeLocker(thread->time_lock);
+				bigtime_t diff = time - thread->CPUTime(false);
+				thread->cpu_clock_offset += diff;
+
+				thread_clock_changed(thread, diff);
+				return B_OK;
+			} else {
+				teamID = clockID & CPUCLOCK_ID_MASK;
+				if (teamID < 0)
+					return B_BAD_VALUE;
+				if (teamID == team_get_kernel_team_id())
+					return B_NOT_ALLOWED;
 			}
 
 			// get the team
@@ -1686,6 +1722,34 @@ _user_set_clock(clockid_t clockID, bigtime_t time)
 }
 
 
+status_t
+_user_get_cpuclockid(thread_id id, int32 which, clockid_t* userclockID)
+{
+	clockid_t clockID;
+	if (which != TEAM_ID && which != THREAD_ID)
+		return B_BAD_VALUE;
+
+	if (which == TEAM_ID) {
+		Team* team = Team::Get(id);
+		if (team == NULL)
+			return B_BAD_VALUE;
+		clockID = id | CPUCLOCK_TEAM;
+	} else if (which == THREAD_ID) {
+		Thread* thread = Thread::Get(id);
+		if (thread == NULL)
+			return B_BAD_VALUE;
+		clockID = id | CPUCLOCK_THREAD;
+	}
+
+	if (userclockID != NULL
+		&& (!IS_USER_ADDRESS(userclockID)
+			|| user_memcpy(userclockID, &clockID, sizeof(clockID)) != B_OK)) {
+		return B_BAD_ADDRESS;
+	}
+	return B_OK;
+}
+
+
 int32
 _user_create_timer(clockid_t clockID, thread_id threadID, uint32 flags,
 	const struct sigevent* userEvent,

src/system/libroot/posix/time/clock_support.cpp

@@ -14,8 +14,10 @@
 #include <OS.h>
 
 #include <errno_private.h>
-#include <time_private.h>
+#include <pthread_private.h>
+#include <syscall_clock_info.h>
 #include <syscall_utils.h>
+#include <time_private.h>
 
 #include <syscalls.h>
 
@@ -145,9 +147,7 @@ clock_getcpuclockid(pid_t pid, clockid_t* _clockID)
 		return 0;
 	}
 
-	// test-get the time to verify the team exists and we have permission
+	status_t error = _kern_get_cpuclockid(pid, TEAM_ID, _clockID);
-	bigtime_t microSeconds;
-	status_t error = _kern_get_clock(pid, &microSeconds);
 	if (error != B_OK) {
 		// Since pid is > 0, B_BAD_VALUE always means a team with that ID
 		// doesn't exist. Translate the error code accordingly.
@@ -156,6 +156,24 @@ clock_getcpuclockid(pid_t pid, clockid_t* _clockID)
 		return error;
 	}
 
-	*_clockID = pid;
+	return 0;
+}
+
+
+int
+pthread_getcpuclockid(pthread_t thread, clockid_t* _clockID)
+{
+	if (thread->id < 0)
+		return ESRCH;
+
+	status_t error = _kern_get_cpuclockid(thread->id, THREAD_ID, _clockID);
+	if (error != B_OK) {
+		// Since thread->id is > 0, B_BAD_VALUE always means a thread with that ID
+		// doesn't exist. Translate the error code accordingly.
+		if (error == B_BAD_VALUE)
+			return ESRCH;
+		return error;
+	}
+
 	return 0;
 }

src/tests/system/libroot/posix/Jamfile

@@ -43,6 +43,7 @@ SimpleTest <test>truncate : truncate.cpp ;
 SimpleTest init_rld_after_fork_test : init_rld_after_fork_test.cpp ;
 SimpleTest user_thread_fork_test : user_thread_fork_test.cpp ;
 SimpleTest pthread_barrier_test : pthread_barrier_test.cpp ;
+SimpleTest pthread_clock_test : pthread_clock_test.cpp ;
 SimpleTest posix_spawn_test : posix_spawn_test.cpp ;
 SimpleTest posix_spawn_redir_test : posix_spawn_redir_test.c ;
 SimpleTest posix_spawn_redir_err : posix_spawn_redir_err.c ;

src/tests/system/libroot/posix/pthread_clock_test.cpp

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2024, Haiku, Inc. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include <pthread.h>
+#include <OS.h>
+
+void*
+threadFn(void* ptr)
+{
+	snooze(1000000);
+	return NULL;
+}
+
+
+int
+main()
+{
+	pthread_t t;
+	pthread_create(&t, NULL, threadFn, NULL);
+
+	clockid_t c;
+	if (pthread_getcpuclockid(t, &c) != 0)
+		return 1;
+	timespec ts;
+	if (clock_gettime(c, &ts) != 0)
+		return 1;
+
+	if (clock_getcpuclockid(getpid(), &c) != 0)
+		return 1;
+	if (clock_gettime(c, &ts) != 0)
+		return 1;
+
+	if (pthread_join(t, NULL) != 0)
+		return 1;
+	return 0;
+}