]> git.saurik.com Git - apple/xnu.git/blobdiff - iokit/Kernel/IOPerfControl.cpp
xnu-6153.11.26.tar.gz
[apple/xnu.git] / iokit / Kernel / IOPerfControl.cpp
index e5ece3480524b95d31bf5a100b8b338d5edb2f73..b3d1a5aac617b9be8c766f8a641a76e07865edc9 100644 (file)
 #define super OSObject
 OSDefineMetaClassAndStructors(IOPerfControlClient, OSObject);
 
-bool IOPerfControlClient::init(IOService *driver, uint64_t maxWorkCapacity)
+static IOPerfControlClient::IOPerfControlClientShared *_Atomic gIOPerfControlClientShared;
+
+bool
+IOPerfControlClient::init(IOService *driver, uint64_t maxWorkCapacity)
 {
-    if (!super::init())
-        return false;
-
-    interface = PerfControllerInterface{
-        .version = 0,
-        .registerDevice =
-            [](IOService *device) {
-                return kIOReturnSuccess;
-            },
-        .unregisterDevice =
-            [](IOService *device) {
-                return kIOReturnSuccess;
-            },
-        .workCanSubmit =
-            [](IOService *device, PerfControllerInterface::WorkState *state, WorkSubmitArgs *args) {
-                return false;
-            },
-        .workSubmit =
-            [](IOService *device, uint64_t token, PerfControllerInterface::WorkState *state, WorkSubmitArgs *args) {
-            },
-        .workBegin =
-            [](IOService *device, uint64_t token, PerfControllerInterface::WorkState *state, WorkBeginArgs *args) {
-            },
-        .workEnd =
-            [](IOService *device, uint64_t token, PerfControllerInterface::WorkState *state, WorkEndArgs *args, bool done) {
-            },
-    };
-
-    interfaceLock = IOLockAlloc();
-    if (!interfaceLock)
-        goto error;
-
-    deviceRegistrationList = OSSet::withCapacity(4);
-    if (!deviceRegistrationList)
-        goto error;
-
-    bzero(workTable, sizeof(workTable));
-    memset(&workTable[kIOPerfControlClientWorkUntracked], ~0, sizeof(WorkTableEntry));
-    workTableNextIndex = kIOPerfControlClientWorkUntracked + 1;
-
-    workTableLock = IOSimpleLockAlloc();
-    if (!workTableLock)
-        goto error;
-
-    // TODO: check sum(maxWorkCapacities) < table size
-
-    return true;
+       // TODO: Remove this limit and implement dynamic table growth if workloads are found that exceed this
+       if (maxWorkCapacity > kMaxWorkTableNumEntries) {
+               maxWorkCapacity = kMaxWorkTableNumEntries;
+       }
+
+       if (!super::init()) {
+               return false;
+       }
+
+       shared = atomic_load_explicit(&gIOPerfControlClientShared, memory_order_acquire);
+       if (shared == nullptr) {
+               IOPerfControlClient::IOPerfControlClientShared *expected = shared;
+               shared = reinterpret_cast<IOPerfControlClient::IOPerfControlClientShared*>(kalloc(sizeof(IOPerfControlClientShared)));
+               if (!shared) {
+                       return false;
+               }
+
+               atomic_init(&shared->maxDriverIndex, 0);
+
+               shared->interface = PerfControllerInterface{
+                       .version = 0,
+                       .registerDevice =
+                   [](IOService *device) {
+                           return kIOReturnSuccess;
+                   },
+                       .unregisterDevice =
+                           [](IOService *device) {
+                                   return kIOReturnSuccess;
+                           },
+                       .workCanSubmit =
+                           [](IOService *device, PerfControllerInterface::WorkState *state, WorkSubmitArgs *args) {
+                                   return false;
+                           },
+                       .workSubmit =
+                           [](IOService *device, uint64_t token, PerfControllerInterface::WorkState *state, WorkSubmitArgs *args) {
+                           },
+                       .workBegin =
+                           [](IOService *device, uint64_t token, PerfControllerInterface::WorkState *state, WorkBeginArgs *args) {
+                           },
+                       .workEnd =
+                           [](IOService *device, uint64_t token, PerfControllerInterface::WorkState *state, WorkEndArgs *args, bool done) {
+                           },
+               };
+
+               shared->interfaceLock = IOLockAlloc();
+               if (!shared->interfaceLock) {
+                       goto shared_init_error;
+               }
+
+               shared->deviceRegistrationList = OSSet::withCapacity(4);
+               if (!shared->deviceRegistrationList) {
+                       goto shared_init_error;
+               }
+
+               if (!atomic_compare_exchange_strong_explicit(&gIOPerfControlClientShared, &expected, shared, memory_order_acq_rel,
+                   memory_order_acquire)) {
+                       IOLockFree(shared->interfaceLock);
+                       shared->deviceRegistrationList->release();
+                       kfree(shared, sizeof(*shared));
+                       shared = expected;
+               }
+       }
+
+       driverIndex = atomic_fetch_add_explicit(&shared->maxDriverIndex, 1, memory_order_relaxed) + 1;
+       assertf(driverIndex != 0, "Overflow in driverIndex. Too many IOPerfControlClients created.\n");
+
+       // + 1 since index 0 is unused for kIOPerfControlClientWorkUntracked
+       workTableLength = maxWorkCapacity + 1;
+       assertf(workTableLength <= kWorkTableMaxSize, "%zu exceeds max allowed capacity of %zu", workTableLength, kWorkTableMaxSize);
+       if (maxWorkCapacity > 0) {
+               workTable = reinterpret_cast<WorkTableEntry*>(kalloc(workTableLength * sizeof(WorkTableEntry)));
+               if (!workTable) {
+                       goto error;
+               }
+               bzero(workTable, workTableLength * sizeof(WorkTableEntry));
+               workTableNextIndex = 1;
+
+               workTableLock = IOSimpleLockAlloc();
+               if (!workTableLock) {
+                       goto error;
+               }
+       }
+
+       return true;
 
 error:
-    if (interfaceLock)
-        IOLockFree(interfaceLock);
-    if (deviceRegistrationList)
-        deviceRegistrationList->release();
-    if (workTableLock)
-        IOSimpleLockFree(workTableLock);
-    return false;
+       if (workTable) {
+               kfree(workTable, maxWorkCapacity * sizeof(WorkTableEntry));
+       }
+       if (workTableLock) {
+               IOSimpleLockFree(workTableLock);
+       }
+       return false;
+shared_init_error:
+       if (shared) {
+               if (shared->interfaceLock) {
+                       IOLockFree(shared->interfaceLock);
+               }
+               if (shared->deviceRegistrationList) {
+                       shared->deviceRegistrationList->release();
+               }
+               kfree(shared, sizeof(*shared));
+               shared = nullptr;
+       }
+       return false;
 }
 
-IOPerfControlClient *_Atomic gSharedClient = nullptr;
+IOPerfControlClient *
+IOPerfControlClient::copyClient(IOService *driver, uint64_t maxWorkCapacity)
+{
+       IOPerfControlClient *client = new IOPerfControlClient;
+       if (!client || !client->init(driver, maxWorkCapacity)) {
+               panic("could not create IOPerfControlClient");
+       }
+       return client;
+}
 
-IOPerfControlClient *IOPerfControlClient::copyClient(IOService *driver, uint64_t maxWorkCapacity)
+/* Convert the per driver token into a globally unique token for the performance
+ * controller's consumption. This is achieved by setting the driver's unique
+ * index onto the high order bits. The performance controller is shared between
+ * all drivers and must track all instances separately, while each driver has
+ * its own token table, so this step is needed to avoid token collisions between
+ * drivers.
+ */
+inline uint64_t
+IOPerfControlClient::tokenToGlobalUniqueToken(uint64_t token)
 {
-    IOPerfControlClient *client = atomic_load_explicit(&gSharedClient, memory_order_acquire);
-    if (client == nullptr) {
-        IOPerfControlClient *expected = client;
-        client = new IOPerfControlClient;
-        if (!client || !client->init(driver, maxWorkCapacity))
-            panic("could not create IOPerfControlClient");
-        if (!atomic_compare_exchange_strong_explicit(&gSharedClient, &expected, client, memory_order_acq_rel,
-                                                     memory_order_acquire)) {
-            client->release();
-            client = expected;
-        }
-    }
-    // TODO: add maxWorkCapacity to existing client
-    client->retain();
-    return client;
+       return token | (static_cast<uint64_t>(driverIndex) << kWorkTableIndexBits);
 }
 
-uint64_t IOPerfControlClient::allocateToken(thread_group *thread_group)
+/* With this implementation, tokens returned to the driver differ from tokens
+ * passed to the performance controller. This implementation has the nice
+ * property that tokens returns to the driver will aways be between 1 and
+ * the value of maxWorkCapacity passed by the driver to copyClient. The tokens
+ * the performance controller sees will match on the lower order bits and have
+ * the driver index set on the high order bits.
+ */
+uint64_t
+IOPerfControlClient::allocateToken(thread_group *thread_group)
 {
-    uint64_t token = kIOPerfControlClientWorkUntracked;
+       uint64_t token = kIOPerfControlClientWorkUntracked;
 
 
-    return token;
+       return token;
 }
 
-void IOPerfControlClient::deallocateToken(uint64_t token)
+void
+IOPerfControlClient::deallocateToken(uint64_t token)
 {
 }
 
-bool IOPerfControlClient::getEntryForToken(uint64_t token, IOPerfControlClient::WorkTableEntry &entry)
+bool
+IOPerfControlClient::getEntryForToken(uint64_t token, IOPerfControlClient::WorkTableEntry &entry)
 {
-    if (token == kIOPerfControlClientWorkUntracked)
-        return false;
-
-    if (token >= kWorkTableNumEntries)
-        panic("Invalid work token (%llu): index out of bounds.", token);
-
-    entry = workTable[token];
-    auto *thread_group = entry.thread_group;
-    assertf(thread_group, "Invalid work token: %llu", token);
-    return thread_group != nullptr;
+       if (token == kIOPerfControlClientWorkUntracked) {
+               return false;
+       }
+
+       if (token >= workTableLength) {
+               panic("Invalid work token (%llu): index out of bounds.", token);
+       }
+
+       entry = workTable[token];
+       auto *thread_group = entry.thread_group;
+       assertf(thread_group, "Invalid work token: %llu", token);
+       return thread_group != nullptr;
 }
 
-void IOPerfControlClient::markEntryStarted(uint64_t token, bool started)
+void
+IOPerfControlClient::markEntryStarted(uint64_t token, bool started)
 {
-    if (token == kIOPerfControlClientWorkUntracked)
-        return;
+       if (token == kIOPerfControlClientWorkUntracked) {
+               return;
+       }
 
-    if (token >= kWorkTableNumEntries)
-        panic("Invalid work token (%llu): index out of bounds.", token);
+       if (token >= workTableLength) {
+               panic("Invalid work token (%llu): index out of bounds.", token);
+       }
 
-    workTable[token].started = started;
+       workTable[token].started = started;
 }
 
-IOReturn IOPerfControlClient::registerDevice(__unused IOService *driver, IOService *device)
+IOReturn
+IOPerfControlClient::registerDevice(__unused IOService *driver, IOService *device)
 {
-    IOReturn ret = kIOReturnSuccess;
+       IOReturn ret = kIOReturnSuccess;
 
-    IOLockLock(interfaceLock);
+       IOLockLock(shared->interfaceLock);
 
-    if (interface.version > 0)
-        ret = interface.registerDevice(device);
-    else
-        deviceRegistrationList->setObject(device);
+       if (shared->interface.version > 0) {
+               ret = shared->interface.registerDevice(device);
+       } else {
+               shared->deviceRegistrationList->setObject(device);
+       }
 
-    IOLockUnlock(interfaceLock);
+       IOLockUnlock(shared->interfaceLock);
 
-    return ret;
+       return ret;
 }
 
-void IOPerfControlClient::unregisterDevice(__unused IOService *driver, IOService *device)
+void
+IOPerfControlClient::unregisterDevice(__unused IOService *driver, IOService *device)
 {
-    IOLockLock(interfaceLock);
+       IOLockLock(shared->interfaceLock);
 
-    if (interface.version > 0)
-        interface.unregisterDevice(device);
-    else
-        deviceRegistrationList->removeObject(device);
+       if (shared->interface.version > 0) {
+               shared->interface.unregisterDevice(device);
+       } else {
+               shared->deviceRegistrationList->removeObject(device);
+       }
 
-    IOLockUnlock(interfaceLock);
+       IOLockUnlock(shared->interfaceLock);
 }
 
-uint64_t IOPerfControlClient::workSubmit(IOService *device, WorkSubmitArgs *args)
+uint64_t
+IOPerfControlClient::workSubmit(IOService *device, WorkSubmitArgs *args)
 {
-    return kIOPerfControlClientWorkUntracked;
+       return kIOPerfControlClientWorkUntracked;
 }
 
-uint64_t IOPerfControlClient::workSubmitAndBegin(IOService *device, WorkSubmitArgs *submitArgs, WorkBeginArgs *beginArgs)
+uint64_t
+IOPerfControlClient::workSubmitAndBegin(IOService *device, WorkSubmitArgs *submitArgs, WorkBeginArgs *beginArgs)
 {
-    return kIOPerfControlClientWorkUntracked;
+       return kIOPerfControlClientWorkUntracked;
 }
 
-void IOPerfControlClient::workBegin(IOService *device, uint64_t token, WorkBeginArgs *args)
+void
+IOPerfControlClient::workBegin(IOService *device, uint64_t token, WorkBeginArgs *args)
 {
 }
 
-void IOPerfControlClient::workEnd(IOService *device, uint64_t token, WorkEndArgs *args, bool done)
+void
+IOPerfControlClient::workEnd(IOService *device, uint64_t token, WorkEndArgs *args, bool done)
 {
 }
 
-IOReturn IOPerfControlClient::registerPerformanceController(PerfControllerInterface pci)
+IOReturn
+IOPerfControlClient::registerPerformanceController(PerfControllerInterface pci)
 {
-    IOReturn result = kIOReturnError;
+       IOReturn result = kIOReturnError;
 
-    IOLockLock(interfaceLock);
+       IOLockLock(shared->interfaceLock);
 
-    if (interface.version == 0 && pci.version > 0) {
-        assert(pci.registerDevice && pci.unregisterDevice && pci.workCanSubmit && pci.workSubmit && pci.workBegin && pci.workEnd);
-        result = kIOReturnSuccess;
+       if (shared->interface.version == 0 && pci.version > 0) {
+               assert(pci.registerDevice && pci.unregisterDevice && pci.workCanSubmit && pci.workSubmit && pci.workBegin && pci.workEnd);
+               result = kIOReturnSuccess;
 
-        OSObject *obj;
-        while ((obj = deviceRegistrationList->getAnyObject())) {
-            IOService *device = OSDynamicCast(IOService, obj);
-            if (device)
-                pci.registerDevice(device);
-            deviceRegistrationList->removeObject(obj);
-        }
+               OSObject *obj;
+               while ((obj = shared->deviceRegistrationList->getAnyObject())) {
+                       IOService *device = OSDynamicCast(IOService, obj);
+                       if (device) {
+                               pci.registerDevice(device);
+                       }
+                       shared->deviceRegistrationList->removeObject(obj);
+               }
 
-        interface = pci;
-    }
+               shared->interface = pci;
+       }
 
-    IOLockUnlock(interfaceLock);
+       IOLockUnlock(shared->interfaceLock);
 
-    return result;
+       return result;
 }