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authorMike Lockwood <lockwood@google.com>2013-10-17 08:05:00 -0700
committerMike Lockwood <lockwood@google.com>2013-12-09 15:26:55 -0800
commitf84776247777ca8710eca8a911f607e10256cc7d (patch)
tree7e3d4a68f572c131f2a4106448852189244030f0 /modules/sensors/multihal.cpp
parent0bd030b5df7381949ff368f15ebca214560fbf22 (diff)
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DO NOT MERGE: Sensor multi HAL
Squashed commit of: Move sensors multi HAL to libhardware Added a SensorEventQueue, a circular buffer meant for reading with one thread and polling a subhal with another. The writing thread gets access to pointers in the internal buffer. This design avoids a memcpy on write when the multihal fetches subhal events using poll(). Unit-tests include multithreaded reading and writing lots of events, in random-sized chunks. This is not used by the multihal yet. That will be a different CL. MultiHal multithreaded polling Tests SensorEventQueue I/O when the queue is full. Reduced debug logging in multihal. deactivated multihal logspam, made warnings warnings, left critical startup info Removed unneeded linux/input.h includes, to fix Mac SDK build Change-Id: I1e35508949df98a1acef7a4a2d012eea87b4a5eb
Diffstat (limited to 'modules/sensors/multihal.cpp')
-rw-r--r--modules/sensors/multihal.cpp586
1 files changed, 586 insertions, 0 deletions
diff --git a/modules/sensors/multihal.cpp b/modules/sensors/multihal.cpp
new file mode 100644
index 0000000..a145c37
--- /dev/null
+++ b/modules/sensors/multihal.cpp
@@ -0,0 +1,586 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <hardware/sensors.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <dirent.h>
+#include <math.h>
+#include <poll.h>
+#include <pthread.h>
+#include <cutils/atomic.h>
+
+#define LOG_NDEBUG 1
+#include <cutils/log.h>
+
+#include <vector>
+#include <map>
+
+#include <stdio.h>
+#include <dlfcn.h>
+#include <SensorEventQueue.h>
+
+
+static const char* CONFIG_FILENAME = "/system/etc/sensors/hals.conf";
+static const char* LEGAL_SUBHAL_PATH_PREFIX = "/system/lib/hw/";
+static const int MAX_CONF_LINE_LENGTH = 1024;
+
+static pthread_mutex_t init_modules_mutex = PTHREAD_MUTEX_INITIALIZER;
+static pthread_mutex_t init_sensors_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+// This mutex is shared by all queues
+static pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+// Used to pause the multihal poll(). Broadcasted by sub-polling tasks if waiting_for_data.
+static pthread_cond_t data_available_cond = PTHREAD_COND_INITIALIZER;
+bool waiting_for_data = false;
+
+/*
+ * Vector of sub modules, whose indexes are referred to ni this file as module_index.
+ */
+static std::vector<hw_module_t *> *sub_hw_modules = NULL;
+
+/*
+ * Comparable class that globally identifies a sensor, by module index and local handle.
+ * A module index is the module's index in sub_hw_modules.
+ * A local handle is the handle the sub-module assigns to a sensor.
+ */
+struct FullHandle {
+ int moduleIndex;
+ int localHandle;
+
+ bool operator<(const FullHandle &that) const {
+ if (moduleIndex < that.moduleIndex) {
+ return true;
+ }
+ if (moduleIndex > that.moduleIndex) {
+ return false;
+ }
+ return localHandle < that.localHandle;
+ }
+
+ bool operator==(const FullHandle &that) const {
+ return moduleIndex == that.moduleIndex && localHandle == that.localHandle;
+ }
+};
+
+std::map<int, FullHandle> global_to_full;
+std::map<FullHandle, int> full_to_global;
+int next_global_handle = 1;
+
+static int assign_global_handle(int module_index, int local_handle) {
+ int global_handle = next_global_handle++;
+ FullHandle full_handle;
+ full_handle.moduleIndex = module_index;
+ full_handle.localHandle = local_handle;
+ full_to_global[full_handle] = global_handle;
+ global_to_full[global_handle] = full_handle;
+ return global_handle;
+}
+
+static int get_local_handle(int global_handle) {
+ return global_to_full[global_handle].localHandle;
+}
+
+static int get_module_index(int global_handle) {
+ FullHandle f = global_to_full[global_handle];
+ ALOGV("FullHandle for global_handle %d: moduleIndex %d, localHandle %d",
+ global_handle, f.moduleIndex, f.localHandle);
+ return f.moduleIndex;
+}
+
+static const int SENSOR_EVENT_QUEUE_CAPACITY = 20;
+
+struct TaskContext {
+ sensors_poll_device_t* device;
+ SensorEventQueue* queue;
+};
+
+void *writerTask(void* ptr) {
+ ALOGV("writerTask STARTS");
+ TaskContext* ctx = (TaskContext*)ptr;
+ sensors_poll_device_t* device = ctx->device;
+ SensorEventQueue* queue = ctx->queue;
+ sensors_event_t* buffer;
+ int eventsPolled;
+ while (1) {
+ pthread_mutex_lock(&queue_mutex);
+ if (queue->waitForSpace(&queue_mutex)) {
+ ALOGV("writerTask waited for space");
+ }
+ int bufferSize = queue->getWritableRegion(SENSOR_EVENT_QUEUE_CAPACITY, &buffer);
+ // Do blocking poll outside of lock
+ pthread_mutex_unlock(&queue_mutex);
+
+ ALOGV("writerTask before poll() - bufferSize = %d", bufferSize);
+ eventsPolled = device->poll(device, buffer, bufferSize);
+ ALOGV("writerTask poll() got %d events.", eventsPolled);
+ if (eventsPolled == 0) {
+ continue;
+ }
+ pthread_mutex_lock(&queue_mutex);
+ queue->markAsWritten(eventsPolled);
+ ALOGV("writerTask wrote %d events", eventsPolled);
+ if (waiting_for_data) {
+ ALOGV("writerTask - broadcast data_available_cond");
+ pthread_cond_broadcast(&data_available_cond);
+ }
+ pthread_mutex_unlock(&queue_mutex);
+ }
+ // never actually returns
+ return NULL;
+}
+
+/*
+ * Cache of all sensors, with original handles replaced by global handles.
+ * This will be handled to get_sensors_list() callers.
+ */
+static struct sensor_t const* global_sensors_list = NULL;
+static int global_sensors_count = -1;
+
+/*
+ * Extends a sensors_poll_device_1 by including all the sub-module's devices.
+ */
+struct sensors_poll_context_t {
+ /*
+ * This is the device that SensorDevice.cpp uses to make API calls
+ * to the multihal, which fans them out to sub-HALs.
+ */
+ sensors_poll_device_1 proxy_device; // must be first
+
+ void addSubHwDevice(struct hw_device_t*);
+
+ int activate(int handle, int enabled);
+ int setDelay(int handle, int64_t ns);
+ int poll(sensors_event_t* data, int count);
+ int batch(int handle, int flags, int64_t period_ns, int64_t timeout);
+ int flush(int handle);
+ int close();
+
+ std::vector<hw_device_t*> sub_hw_devices;
+ std::vector<SensorEventQueue*> queues;
+ std::vector<pthread_t> threads;
+ int nextReadIndex;
+
+ sensors_poll_device_t* get_v0_device_by_handle(int global_handle);
+ sensors_poll_device_1_t* get_v1_device_by_handle(int global_handle);
+ int get_device_version_by_handle(int global_handle);
+
+ void copy_event_remap_handle(sensors_event_t* src, sensors_event_t* dest, int sub_index);
+};
+
+void sensors_poll_context_t::addSubHwDevice(struct hw_device_t* sub_hw_device) {
+ ALOGV("addSubHwDevice");
+ this->sub_hw_devices.push_back(sub_hw_device);
+
+ SensorEventQueue *queue = new SensorEventQueue(SENSOR_EVENT_QUEUE_CAPACITY);
+ this->queues.push_back(queue);
+
+ TaskContext* taskContext = new TaskContext();
+ taskContext->device = (sensors_poll_device_t*) sub_hw_device;
+ taskContext->queue = queue;
+
+ pthread_t writerThread;
+ pthread_create(&writerThread, NULL, writerTask, taskContext);
+ this->threads.push_back(writerThread);
+}
+
+sensors_poll_device_t* sensors_poll_context_t::get_v0_device_by_handle(int handle) {
+ int sub_index = get_module_index(handle);
+ return (sensors_poll_device_t*) this->sub_hw_devices[sub_index];
+}
+
+sensors_poll_device_1_t* sensors_poll_context_t::get_v1_device_by_handle(int handle) {
+ int sub_index = get_module_index(handle);
+ return (sensors_poll_device_1_t*) this->sub_hw_devices[sub_index];
+}
+
+int sensors_poll_context_t::get_device_version_by_handle(int handle) {
+ sensors_poll_device_t* v0 = this->get_v0_device_by_handle(handle);
+ return v0->common.version;
+}
+
+int sensors_poll_context_t::activate(int handle, int enabled) {
+ ALOGV("activate");
+ sensors_poll_device_t* v0 = this->get_v0_device_by_handle(handle);
+ int retval = v0->activate(v0, get_local_handle(handle), enabled);
+ ALOGV("retval %d", retval);
+ return retval;
+}
+
+int sensors_poll_context_t::setDelay(int handle, int64_t ns) {
+ ALOGV("setDelay");
+ sensors_poll_device_t* v0 = this->get_v0_device_by_handle(handle);
+ int retval = v0->setDelay(v0, get_local_handle(handle), ns);
+ ALOGV("retval %d", retval);
+ return retval;
+}
+
+void sensors_poll_context_t::copy_event_remap_handle(sensors_event_t* dest, sensors_event_t* src,
+ int sub_index) {
+ memcpy(dest, src, sizeof(struct sensors_event_t));
+ // A normal event's "sensor" field is a local handle. Convert it to a global handle.
+ // A meta-data event must have its sensor set to 0, but it has a nested event
+ // with a local handle that needs to be converted to a global handle.
+ FullHandle full_handle;
+ full_handle.moduleIndex = sub_index;
+ // If it's a metadata event, rewrite the inner payload, not the sensor field.
+ if (dest->type == SENSOR_TYPE_META_DATA) {
+ full_handle.localHandle = dest->meta_data.sensor;
+ dest->meta_data.sensor = full_to_global[full_handle];
+ } else {
+ full_handle.localHandle = dest->sensor;
+ dest->sensor = full_to_global[full_handle];
+ }
+}
+
+int sensors_poll_context_t::poll(sensors_event_t *data, int maxReads) {
+ ALOGV("poll");
+ int empties = 0;
+ int queueCount = (int)this->queues.size();
+ int eventsRead = 0;
+
+ pthread_mutex_lock(&queue_mutex);
+ while (eventsRead == 0) {
+ while (empties < queueCount && eventsRead < maxReads) {
+ SensorEventQueue* queue = this->queues.at(this->nextReadIndex);
+ sensors_event_t* event = queue->peek();
+ if (event == NULL) {
+ empties++;
+ } else {
+ empties = 0;
+ this->copy_event_remap_handle(&data[eventsRead++], event, nextReadIndex);
+ queue->dequeue();
+ }
+ this->nextReadIndex = (this->nextReadIndex + 1) % queueCount;
+ }
+ if (eventsRead == 0) {
+ // The queues have been scanned and none contain data, so wait.
+ ALOGV("poll stopping to wait for data");
+ waiting_for_data = true;
+ pthread_cond_wait(&data_available_cond, &queue_mutex);
+ waiting_for_data = false;
+ empties = 0;
+ }
+ }
+ pthread_mutex_unlock(&queue_mutex);
+ ALOGV("poll returning %d events.", eventsRead);
+
+ return eventsRead;
+}
+
+int sensors_poll_context_t::batch(int handle, int flags, int64_t period_ns, int64_t timeout) {
+ ALOGV("batch");
+ int retval = -EINVAL;
+ int version = this->get_device_version_by_handle(handle);
+ if (version >= SENSORS_DEVICE_API_VERSION_1_0) {
+ sensors_poll_device_1_t* v1 = this->get_v1_device_by_handle(handle);
+ retval = v1->batch(v1, get_local_handle(handle), flags, period_ns, timeout);
+ }
+ ALOGV("retval %d", retval);
+ return retval;
+}
+
+int sensors_poll_context_t::flush(int handle) {
+ ALOGV("flush");
+ int retval = -EINVAL;
+ int version = this->get_device_version_by_handle(handle);
+ if (version >= SENSORS_DEVICE_API_VERSION_1_0) {
+ sensors_poll_device_1_t* v1 = this->get_v1_device_by_handle(handle);
+ retval = v1->flush(v1, get_local_handle(handle));
+ }
+ ALOGV("retval %d", retval);
+ return retval;
+}
+
+int sensors_poll_context_t::close() {
+ ALOGV("close");
+ for (std::vector<hw_device_t*>::iterator it = this->sub_hw_devices.begin();
+ it != this->sub_hw_devices.end(); it++) {
+ hw_device_t* dev = *it;
+ int retval = dev->close(dev);
+ ALOGV("retval %d", retval);
+ }
+ return 0;
+}
+
+
+static int device__close(struct hw_device_t *dev) {
+ sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev;
+ if (ctx != NULL) {
+ int retval = ctx->close();
+ delete ctx;
+ }
+ return 0;
+}
+
+static int device__activate(struct sensors_poll_device_t *dev, int handle,
+ int enabled) {
+ sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev;
+ return ctx->activate(handle, enabled);
+}
+
+static int device__setDelay(struct sensors_poll_device_t *dev, int handle,
+ int64_t ns) {
+ sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev;
+ return ctx->setDelay(handle, ns);
+}
+
+static int device__poll(struct sensors_poll_device_t *dev, sensors_event_t* data,
+ int count) {
+ sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev;
+ return ctx->poll(data, count);
+}
+
+static int device__batch(struct sensors_poll_device_1 *dev, int handle,
+ int flags, int64_t period_ns, int64_t timeout) {
+ sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev;
+ return ctx->batch(handle, flags, period_ns, timeout);
+}
+
+static int device__flush(struct sensors_poll_device_1 *dev, int handle) {
+ sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev;
+ return ctx->flush(handle);
+}
+
+static int open_sensors(const struct hw_module_t* module, const char* name,
+ struct hw_device_t** device);
+
+static bool starts_with(const char* s, const char* prefix) {
+ if (s == NULL || prefix == NULL) {
+ return false;
+ }
+ size_t s_size = strlen(s);
+ size_t prefix_size = strlen(prefix);
+ return s_size >= prefix_size && strncmp(s, prefix, prefix_size) == 0;
+}
+
+/*
+ * Adds valid paths from the config file to the vector passed in.
+ * The vector must not be null.
+ */
+static void get_so_paths(std::vector<char*> *so_paths) {
+ FILE *conf_file = fopen(CONFIG_FILENAME, "r");
+ if (conf_file == NULL) {
+ ALOGW("No multihal config file found at %s", CONFIG_FILENAME);
+ return;
+ }
+ ALOGI("Multihal config file found at %s", CONFIG_FILENAME);
+ char *line = NULL;
+ size_t len = 0;
+ int line_count = 0;
+ while (getline(&line, &len, conf_file) != -1) {
+ // overwrite trailing eoln with null char
+ char* pch = strchr(line, '\n');
+ if (pch != NULL) {
+ *pch = '\0';
+ }
+ ALOGV("config file line #%d: '%s'", ++line_count, line);
+ char *real_path = realpath(line, NULL);
+ if (starts_with(real_path, LEGAL_SUBHAL_PATH_PREFIX)) {
+ ALOGI("accepting valid path '%s'", real_path);
+ char* compact_line = new char[strlen(real_path) + 1];
+ strcpy(compact_line, real_path);
+ so_paths->push_back(compact_line);
+ } else {
+ ALOGW("rejecting path '%s' because it does not start with '%s'",
+ real_path, LEGAL_SUBHAL_PATH_PREFIX);
+ }
+ free(real_path);
+ }
+ free(line);
+ fclose(conf_file);
+ ALOGV("hals.conf contained %d lines", line_count);
+}
+
+/*
+ * Ensures that the sub-module array is initialized.
+ * This can be first called from get_sensors_list or from open_sensors.
+ */
+static void lazy_init_modules() {
+ pthread_mutex_lock(&init_modules_mutex);
+ if (sub_hw_modules != NULL) {
+ pthread_mutex_unlock(&init_modules_mutex);
+ return;
+ }
+ std::vector<char*> *so_paths = new std::vector<char*>();
+ get_so_paths(so_paths);
+
+ // dlopen the module files and cache their module symbols in sub_hw_modules
+ sub_hw_modules = new std::vector<hw_module_t *>();
+ dlerror(); // clear any old errors
+ const char* sym = HAL_MODULE_INFO_SYM_AS_STR;
+ for (std::vector<char*>::iterator it = so_paths->begin(); it != so_paths->end(); it++) {
+ char* path = *it;
+ void* lib_handle = dlopen(path, RTLD_LAZY);
+ if (lib_handle == NULL) {
+ ALOGW("dlerror(): %s", dlerror());
+ } else {
+ ALOGI("hal lib was loaded: %s", path);
+ ALOGV("Opening symbol \"%s\"", sym);
+ // clear old errors
+ dlerror();
+ struct hw_module_t* module = (hw_module_t*) dlsym(lib_handle, sym);
+ const char* error;
+ if ((error = dlerror()) != NULL) {
+ ALOGW("Error calling dlsym: %s", error);
+ } else if (module == NULL) {
+ ALOGW("module == NULL");
+ } else {
+ ALOGI("OK, dlsym()'ed \"%s\"", sym);
+ sub_hw_modules->push_back(module);
+ }
+ }
+ }
+ pthread_mutex_unlock(&init_modules_mutex);
+}
+
+/*
+ * Lazy-initializes global_sensors_count, global_sensors_list, and module_sensor_handles.
+ */
+static void lazy_init_sensors_list() {
+ ALOGV("lazy_init_sensors_list");
+ pthread_mutex_lock(&init_sensors_mutex);
+ if (global_sensors_list != NULL) {
+ // already initialized
+ pthread_mutex_unlock(&init_sensors_mutex);
+ ALOGV("lazy_init_sensors_list - early return");
+ return;
+ }
+
+ ALOGV("lazy_init_sensors_list needs to do work");
+ lazy_init_modules();
+
+ // Count all the sensors, then allocate an array of blanks.
+ global_sensors_count = 0;
+ const struct sensor_t *subhal_sensors_list;
+ for (std::vector<hw_module_t*>::iterator it = sub_hw_modules->begin();
+ it != sub_hw_modules->end(); it++) {
+ struct sensors_module_t *module = (struct sensors_module_t*) *it;
+ global_sensors_count += module->get_sensors_list(module, &subhal_sensors_list);
+ ALOGV("increased global_sensors_count to %d", global_sensors_count);
+ }
+
+ // The global_sensors_list is full of consts.
+ // Manipulate this non-const list, and point the const one to it when we're done.
+ sensor_t* mutable_sensor_list = new sensor_t[global_sensors_count];
+
+ // index of the next sensor to set in mutable_sensor_list
+ int mutable_sensor_index = 0;
+ int module_index = 0;
+
+ for (std::vector<hw_module_t*>::iterator it = sub_hw_modules->begin();
+ it != sub_hw_modules->end(); it++) {
+ hw_module_t *hw_module = *it;
+ ALOGV("examine one module");
+ // Read the sub-module's sensor list.
+ struct sensors_module_t *module = (struct sensors_module_t*) hw_module;
+ int module_sensor_count = module->get_sensors_list(module, &subhal_sensors_list);
+ ALOGV("the module has %d sensors", module_sensor_count);
+
+ // Copy the HAL's sensor list into global_sensors_list,
+ // with the handle changed to be a global handle.
+ for (int i = 0; i < module_sensor_count; i++) {
+ ALOGV("examining one sensor");
+ const struct sensor_t *local_sensor = &subhal_sensors_list[i];
+ int local_handle = local_sensor->handle;
+ memcpy(&mutable_sensor_list[mutable_sensor_index], local_sensor,
+ sizeof(struct sensor_t));
+
+ // Overwrite the global version's handle with a global handle.
+ int global_handle = assign_global_handle(module_index, local_handle);
+
+ mutable_sensor_list[mutable_sensor_index].handle = global_handle;
+ ALOGI("module_index %d, local_handle %d, global_handle %d",
+ module_index, local_handle, global_handle);
+
+ mutable_sensor_index++;
+ }
+ module_index++;
+ }
+ // Set the const static global_sensors_list to the mutable one allocated by this function.
+ global_sensors_list = mutable_sensor_list;
+
+ pthread_mutex_unlock(&init_sensors_mutex);
+ ALOGV("end lazy_init_sensors_list");
+}
+
+static int module__get_sensors_list(struct sensors_module_t* module,
+ struct sensor_t const** list) {
+ ALOGV("module__get_sensors_list start");
+ lazy_init_sensors_list();
+ *list = global_sensors_list;
+ ALOGV("global_sensors_count: %d", global_sensors_count);
+ for (int i = 0; i < global_sensors_count; i++) {
+ ALOGV("sensor type: %d", global_sensors_list[i].type);
+ }
+ return global_sensors_count;
+}
+
+static struct hw_module_methods_t sensors_module_methods = {
+ open : open_sensors
+};
+
+struct sensors_module_t HAL_MODULE_INFO_SYM = {
+ common :{
+ tag : HARDWARE_MODULE_TAG,
+ version_major : 1,
+ version_minor : 0,
+ id : SENSORS_HARDWARE_MODULE_ID,
+ name : "MultiHal Sensor Module",
+ author : "Google, Inc",
+ methods : &sensors_module_methods,
+ dso : NULL,
+ reserved : {0},
+ },
+ get_sensors_list : module__get_sensors_list
+};
+
+static int open_sensors(const struct hw_module_t* hw_module, const char* name,
+ struct hw_device_t** hw_device_out) {
+ ALOGI("open_sensors begin...");
+
+ lazy_init_modules();
+
+ // Create proxy device, to return later.
+ sensors_poll_context_t *dev = new sensors_poll_context_t();
+ memset(dev, 0, sizeof(sensors_poll_device_1_t));
+ dev->proxy_device.common.tag = HARDWARE_DEVICE_TAG;
+ dev->proxy_device.common.version = SENSORS_DEVICE_API_VERSION_1_0;
+ dev->proxy_device.common.module = const_cast<hw_module_t*>(hw_module);
+ dev->proxy_device.common.close = device__close;
+ dev->proxy_device.activate = device__activate;
+ dev->proxy_device.setDelay = device__setDelay;
+ dev->proxy_device.poll = device__poll;
+ dev->proxy_device.batch = device__batch;
+ dev->proxy_device.flush = device__flush;
+
+ dev->nextReadIndex = 0;
+
+ // Open() the subhal modules. Remember their devices in a vector parallel to sub_hw_modules.
+ for (std::vector<hw_module_t*>::iterator it = sub_hw_modules->begin();
+ it != sub_hw_modules->end(); it++) {
+ sensors_module_t *sensors_module = (sensors_module_t*) *it;
+ struct hw_device_t* sub_hw_device;
+ int sub_open_result = sensors_module->common.methods->open(*it, name, &sub_hw_device);
+ dev->addSubHwDevice(sub_hw_device);
+ }
+
+ // Prepare the output param and return
+ *hw_device_out = &dev->proxy_device.common;
+ ALOGI("...open_sensors end");
+ return 0;
+}