kernel: Change Thread::team_lock to rw_spinlock

headers/private/kernel/thread_types.h

@@ -483,7 +483,7 @@ struct Thread : TeamThreadIteratorEntry<thread_id>, KernelReferenceable,
 
 	BKernel::Team	*team;	// protected by team lock, thread lock, scheduler
 							// lock, team_lock
-	spinlock		team_lock;
+	rw_spinlock		team_lock;
 
 	struct {
 		sem_id		sem;		// immutable after thread creation

src/system/kernel/UserEvent.cpp

@@ -169,7 +169,7 @@ ThreadSignalEvent::Fire()
 
 	fSignal->AcquireReference();
 		// one reference is transferred to send_signal_to_team_locked
-	InterruptsSpinLocker teamLocker(fThread->team_lock);
+	InterruptsReadSpinLocker teamLocker(fThread->team_lock);
 	SpinLocker locker(fThread->team->signal_lock);
 	status_t error = send_signal_to_thread_locked(fThread, fSignal->Number(),
 		fSignal, B_DO_NOT_RESCHEDULE);

src/system/kernel/signal.cpp

@@ -1494,7 +1494,7 @@ send_signal_to_thread(Thread* thread, const Signal& signal, uint32 flags)
 	if (error != B_OK)
 		return error;
 
-	InterruptsSpinLocker teamLocker(thread->team_lock);
+	InterruptsReadSpinLocker teamLocker(thread->team_lock);
 	SpinLocker locker(thread->team->signal_lock);
 
 	error = send_signal_to_thread_locked(thread, signal.Number(), signalToQueue,

src/system/kernel/thread.cpp

@@ -206,7 +206,7 @@ Thread::Thread(const char* name, thread_id threadID, struct cpu_ent* cpu)
 	mutex_init_etc(&fLock, lockName, MUTEX_FLAG_CLONE_NAME);
 
 	B_INITIALIZE_SPINLOCK(&time_lock);
-	B_INITIALIZE_SPINLOCK(&team_lock);
+	B_INITIALIZE_RW_SPINLOCK(&team_lock);
 
 	// init name
 	if (name != NULL)
@@ -1984,7 +1984,7 @@ thread_exit(void)
 		// swap address spaces, to make sure we're running on the kernel's pgdir
 		vm_swap_address_space(team->address_space, VMAddressSpace::Kernel());
 
-		SpinLocker teamLocker(thread->team_lock);
+		WriteSpinLocker teamLocker(thread->team_lock);
 		SpinLocker schedulerLocker(gSchedulerLock);
 			// removing the thread and putting its death entry to the parent
 			// team needs to be an atomic operation
@@ -3281,7 +3281,7 @@ _user_cancel_thread(thread_id threadID, void (*cancelFunction)(int))
 	thread->cancel_function = cancelFunction;
 
 	// send the cancellation signal to the thread
-	InterruptsSpinLocker teamLocker(thread->team_lock);
+	InterruptsReadSpinLocker teamLocker(thread->team_lock);
 	SpinLocker locker(thread->team->signal_lock);
 	return send_signal_to_thread_locked(thread, SIGNAL_CANCEL_THREAD, NULL, 0);
 }