usb: trigger the explore thread when a bus is added

this helps to find the boot disk, otherwise it can happen that the usb disk driver misses a bus to explore. Change-Id: I6983b42cf66f946b4ba9763ec09b6e4a848f2e9a Reviewed-on: https://review.haiku-os.org/c/haiku/+/5712 Reviewed-by: waddlesplash <[email protected]> Tested-by: Commit checker robot <[email protected]>
calcium9 · Oct 3, 2022 · 3f7abfc · 3f7abfc
1 parent 547ddb9
commit 3f7abfc
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Showing 3 changed files with 27 additions and 6 deletions.
diff --git a/src/add-ons/kernel/bus_managers/usb/Stack.cpp b/src/add-ons/kernel/bus_managers/usb/Stack.cpp
@@ -20,7 +20,7 @@
 Stack::Stack()
 	:	fExploreThread(-1),
 		fFirstExploreDone(false),
-		fStopThreads(false),
+		fExploreSem(-1),
 		fAllocator(NULL),
 		fObjectIndex(1),
 		fObjectMaxCount(1024),
@@ -31,6 +31,12 @@ Stack::Stack()
 
 	mutex_init(&fStackLock, "usb stack lock");
 	mutex_init(&fExploreLock, "usb explore lock");
+	fExploreSem = create_sem(0, "usb explore sem");
+	if (fExploreSem < B_OK) {
+		TRACE_ERROR("failed to create semaphore\n");
+		return;
+	}
+
 
 	size_t objectArraySize = fObjectMaxCount * sizeof(Object *);
 	fObjectArray = (Object **)malloc(objectArraySize);
@@ -65,7 +71,8 @@ Stack::Stack()
 Stack::~Stack()
 {
 	int32 result;
-	fStopThreads = true;
+	delete_sem(fExploreSem);
+	fExploreSem = -1;
 	wait_for_thread(fExploreThread, &result);
 
 	mutex_lock(&fStackLock);
@@ -202,10 +209,16 @@ Stack::ExploreThread(void *data)
 {
 	Stack *stack = (Stack *)data;
 
-	while (!stack->fStopThreads) {
+	while (acquire_sem_etc(stack->fExploreSem, 1, B_RELATIVE_TIMEOUT,
+		USB_DELAY_HUB_EXPLORE) != B_BAD_SEM_ID) {
 		if (mutex_lock(&stack->fExploreLock) != B_OK)
 			break;
 
+		int32 semCount = 0;
+		get_sem_count(stack->fExploreSem, &semCount);
+		if (semCount > 0)
+			acquire_sem_etc(stack->fExploreSem, semCount, B_RELATIVE_TIMEOUT, 0);
+
 		rescan_item *rescanList = NULL;
 		change_item *changeItem = NULL;
 		for (int32 i = 0; i < stack->fBusManagers.Count(); i++) {
@@ -230,7 +243,6 @@ Stack::ExploreThread(void *data)
 		stack->fFirstExploreDone = true;
 		mutex_unlock(&stack->fExploreLock);
 		stack->RescanDrivers(rescanList);
-		snooze(USB_DELAY_HUB_EXPLORE);
 	}
 
 	return B_OK;
@@ -508,3 +520,10 @@ Stack::UninstallNotify(const char *driverName)
 
 	return B_NAME_NOT_FOUND;
 }
+
+
+void
+Stack::TriggerExplore()
+{
+	release_sem(fExploreSem);
+}
diff --git a/src/add-ons/kernel/bus_managers/usb/usb.cpp b/src/add-ons/kernel/bus_managers/usb/usb.cpp
@@ -898,7 +898,7 @@ struct usb_module_info_v2 gModuleInfoV2 = {
 status_t
 usb_added_device(device_node *parent)
 {
-	dprintf("usb_added_device\n");
+	gUSBStack->TriggerExplore();
 	return B_OK;
 }
 

diff --git a/src/add-ons/kernel/bus_managers/usb/usb_private.h b/src/add-ons/kernel/bus_managers/usb/usb_private.h
@@ -165,13 +165,15 @@ class Stack {
 		usb_id							USBID() const { return 0; }
 		const char *					TypeName() const { return "stack"; }
 
+		void							TriggerExplore();
+
 private:
 static	int32							ExploreThread(void *data);
 
 		Vector<BusManager *>			fBusManagers;
 		thread_id						fExploreThread;
 		bool							fFirstExploreDone;
-		bool							fStopThreads;
+		sem_id							fExploreSem;
 
 		mutex							fStackLock;
 		mutex							fExploreLock;