XHCI: Granularize locking.

This is not so important now (though it is a mild performance improvement
when running transfers during commands), but it will be when the debug
transfer hooks are implemented, as we will need to use these to determine
if it is safe to queue and poll for transfers or not.

src/add-ons/kernel/busses/usb/xhci.cpp

@@ -189,16 +189,16 @@ XHCI::XHCI(pci_info *info, Stack *stack)
 		fErstArea(-1),
 		fDcbaArea(-1),
 		fCmdCompSem(-1),
-		fFinishTransfersSem(-1),
-		fFinishThread(-1),
 		fStopThreads(false),
-		fFinishedHead(NULL),
 		fRootHub(NULL),
 		fRootHubAddress(0),
 		fPortCount(0),
 		fSlotCount(0),
 		fScratchpadCount(0),
 		fContextSizeShift(0),
+		fFinishedHead(NULL),
+		fFinishTransfersSem(-1),
+		fFinishThread(-1),
 		fEventSem(-1),
 		fEventThread(-1),
 		fEventIdx(0),
@@ -207,6 +207,8 @@ XHCI::XHCI(pci_info *info, Stack *stack)
 		fCmdCcs(1)
 {
 	B_INITIALIZE_SPINLOCK(&fSpinlock);
+	mutex_init(&fFinishedLock, "XHCI finished transfers");
+	mutex_init(&fEventLock, "XHCI event handler");
 
 	if (BusManager::InitCheck() < B_OK) {
 		TRACE_ERROR("bus manager failed to init\n");
@@ -402,6 +404,9 @@ XHCI::~XHCI()
 	wait_for_thread(fFinishThread, &result);
 	wait_for_thread(fEventThread, &result);
 
+	mutex_destroy(&fFinishedLock);
+	mutex_destroy(&fEventLock);
+
 	remove_io_interrupt_handler(fIRQ, InterruptHandler, (void *)this);
 
 	delete_area(fRegisterArea);
@@ -2114,11 +2119,13 @@ XHCI::HandleTransferComplete(xhci_trb* trb)
 
 			td->trb_completion_code = completionCode;
 			td->trb_left = remainder;
+
 			// add descriptor to finished list
-			Lock();
+			mutex_lock(&fFinishedLock);
 			td->next = fFinishedHead;
 			fFinishedHead = td;
-			Unlock();
+			mutex_unlock(&fFinishedLock);
+
 			release_sem(fFinishTransfersSem);
 			TRACE("HandleTransferComplete td %p done\n", td);
 		} else {
@@ -2361,6 +2368,16 @@ XHCI::CompleteEvents()
 		if (semCount > 0)
 			acquire_sem_etc(fEventSem, semCount, B_RELATIVE_TIMEOUT, 0);
 
+		ProcessEvents();
+	}
+}
+
+
+void
+XHCI::ProcessEvents()
+{
+	MutexLocker _(fEventLock);
+
 	uint16 i = fEventIdx;
 	uint8 j = fEventCcs;
 	uint8 t = 2;
@@ -2406,7 +2423,6 @@ XHCI::CompleteEvents()
 	addr |= ERST_EHB;
 	WriteRunReg32(XHCI_ERDP_LO(0), (uint32)addr);
 	WriteRunReg32(XHCI_ERDP_HI(0), (uint32)(addr >> 32));
-	}
 }
 
 
@@ -2431,13 +2447,13 @@ XHCI::FinishTransfers()
 		if (semCount > 0)
 			acquire_sem_etc(fFinishTransfersSem, semCount, B_RELATIVE_TIMEOUT, 0);
 
-		Lock();
+		mutex_lock(&fFinishedLock);
 		TRACE("finishing transfers\n");
 		while (fFinishedHead != NULL) {
 			xhci_td* td = fFinishedHead;
 			fFinishedHead = td->next;
 			td->next = NULL;
-			Unlock();
+			mutex_unlock(&fFinishedLock);
 
 			TRACE("finishing transfer td %p\n", td);
 
@@ -2495,9 +2511,9 @@ XHCI::FinishTransfers()
 			transfer->Finished(callbackStatus, actualLength);
 			delete transfer;
 			FreeDescriptor(td);
-			Lock();
+			mutex_lock(&fFinishedLock);
 		}
-		Unlock();
+		mutex_unlock(&fFinishedLock);
 	}
 }
 

src/add-ons/kernel/busses/usb/xhci.h

@@ -139,6 +139,7 @@ private:
 			// Event management
 	static	int32				EventThread(void *data);
 			void				CompleteEvents();
+			void				ProcessEvents();
 
 			// Transfer management
 	static	int32				FinishThread(void *data);
@@ -242,12 +243,8 @@ private:
 			spinlock			fSpinlock;
 
 			sem_id				fCmdCompSem;
-			sem_id				fFinishTransfersSem;
-			thread_id			fFinishThread;
 			bool				fStopThreads;
 
-			xhci_td	*			fFinishedHead;
-
 			// Root Hub
 			XHCIRootHub *		fRootHub;
 			uint8				fRootHubAddress;
@@ -267,8 +264,16 @@ private:
 			struct xhci_device	fDevices[XHCI_MAX_DEVICES];
 			int32				fContextSizeShift; // 0/1 for 32/64 bytes
 
+			// Transfers
+			mutex				fFinishedLock;
+			xhci_td	*			fFinishedHead;
+			sem_id				fFinishTransfersSem;
+			thread_id			fFinishThread;
+
+			// Events
 			sem_id				fEventSem;
 			thread_id			fEventThread;
+			mutex				fEventLock;
 			uint16				fEventIdx;
 			uint16				fCmdIdx;
 			uint8				fEventCcs;