alarm.cc revision 49a86709488e5cfd5e23759da18bf9613e15b04d
1f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati/****************************************************************************** 2f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * 3f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * Copyright (C) 2014 Google, Inc. 4f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * 5f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * Licensed under the Apache License, Version 2.0 (the "License"); 6f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * you may not use this file except in compliance with the License. 7f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * You may obtain a copy of the License at: 8f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * 9f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * http://www.apache.org/licenses/LICENSE-2.0 10f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * 11f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * Unless required by applicable law or agreed to in writing, software 12f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * distributed under the License is distributed on an "AS IS" BASIS, 13f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * See the License for the specific language governing permissions and 15f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * limitations under the License. 16f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati * 17f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati ******************************************************************************/ 18f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 19f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati#define LOG_TAG "bt_osi_alarm" 20f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 2149a86709488e5cfd5e23759da18bf9613e15b04dMarie Janssen#include "osi/include/alarm.h" 2249a86709488e5cfd5e23759da18bf9613e15b04dMarie Janssen 23f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati#include <assert.h> 24f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati#include <errno.h> 251afbe154a89ad462de739704ce70eed0e32cbc00Michael Wright#include <inttypes.h> 26b9164f414b4d8d414358d0146a8f911207af3122Elliott Hughes#include <malloc.h> 2749a86709488e5cfd5e23759da18bf9613e15b04dMarie Janssen#include <pthread.h> 28468e4b983dd59ea58a7518032fa6029b00c56dc4Ian Coolidge#include <signal.h> 2949a86709488e5cfd5e23759da18bf9613e15b04dMarie Janssen#include <string.h> 30f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati#include <time.h> 31f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 3249a86709488e5cfd5e23759da18bf9613e15b04dMarie Janssen#include <hardware/bluetooth.h> 3349a86709488e5cfd5e23759da18bf9613e15b04dMarie Janssen 34081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson#include "osi/include/allocator.h" 350f9b91e150e153229235c163861198e23600e636Sharvil Nanavati#include "osi/include/list.h" 3644802768c447ab480d4227b3a852a97d923b816dSharvil Nanavati#include "osi/include/log.h" 37081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson#include "osi/include/osi.h" 38081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson#include "osi/include/semaphore.h" 39081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson#include "osi/include/thread.h" 40f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 41f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistruct alarm_t { 42f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // The lock is held while the callback for this alarm is being executed. 43f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // It allows us to release the coarse-grained monitor lock while a potentially 44f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // long-running callback is executing. |alarm_cancel| uses this lock to provide 45f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // a guarantee to its caller that the callback will not be in progress when it 46f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // returns. 47f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_t callback_lock; 48f2bf2308e90386754080a4fd7cc2ee7751eeab46Sharvil Nanavati period_ms_t creation_time; 49e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson period_ms_t period; 50f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati period_ms_t deadline; 51e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson bool is_periodic; 52f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm_callback_t callback; 53f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati void *data; 54f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati}; 55f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 56f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatiextern bt_os_callouts_t *bt_os_callouts; 57f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 58f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// If the next wakeup time is less than this threshold, we should acquire 59f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// a wakelock instead of setting a wake alarm so we're not bouncing in 60f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// and out of suspend frequently. This value is externally visible to allow 61f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// unit tests to run faster. It should not be modified by production code. 62f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatiint64_t TIMER_INTERVAL_FOR_WAKELOCK_IN_MS = 3000; 63f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic const clockid_t CLOCK_ID = CLOCK_BOOTTIME; 64f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic const char *WAKE_LOCK_ID = "bluedroid_timer"; 65f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 66f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// This mutex ensures that the |alarm_set|, |alarm_cancel|, and alarm callback 67f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// functions execute serially and not concurrently. As a result, this mutex also 68f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// protects the |alarms| list. 69f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic pthread_mutex_t monitor; 70f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic list_t *alarms; 71f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic timer_t timer; 72f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic bool timer_set; 73f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 74081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson// All alarm callbacks are dispatched from |callback_thread| 75081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnsonstatic thread_t *callback_thread; 76cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbachstatic bool callback_thread_active; 77081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnsonstatic semaphore_t *alarm_expired; 78081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 79f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic bool lazy_initialize(void); 80f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic period_ms_t now(void); 8171864f490d4dc31857df0b31924cd62a337e9f1aZach Johnsonstatic void alarm_set_internal(alarm_t *alarm, period_ms_t deadline, alarm_callback_t cb, void *data, bool is_periodic); 82952d180f37fa4f8427eaa190b4c78601c18d2ae0Zach Johnsonstatic void schedule_next_instance(alarm_t *alarm, bool force_reschedule); 83e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnsonstatic void reschedule_root_alarm(void); 84f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic void timer_callback(void *data); 85081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnsonstatic void callback_dispatch(void *context); 86f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 87f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatialarm_t *alarm_new(void) { 88f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // Make sure we have a list we can insert alarms into. 89f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (!alarms && !lazy_initialize()) 90f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return NULL; 91f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 92f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutexattr_t attr; 93f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutexattr_init(&attr); 94f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 95ee2aa45def216a3c4d6a23481fa96f1b02a5de8cZach Johnson alarm_t *ret = osi_calloc(sizeof(alarm_t)); 96f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (!ret) { 97db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to allocate memory for alarm.", __func__); 98f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati goto error; 99f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 100f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 101f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // Make this a recursive mutex to make it safe to call |alarm_cancel| from 102f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // within the callback function of the alarm. 103f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati int error = pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); 104f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (error) { 105db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to create a recursive mutex: %s", __func__, strerror(error)); 106f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati goto error; 107f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 108f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 109f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati error = pthread_mutex_init(&ret->callback_lock, &attr); 110f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (error) { 111db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to initialize mutex: %s", __func__, strerror(error)); 112f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati goto error; 113f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 114f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 115f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutexattr_destroy(&attr); 116f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return ret; 117f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 118f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatierror:; 119f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutexattr_destroy(&attr); 120ee2aa45def216a3c4d6a23481fa96f1b02a5de8cZach Johnson osi_free(ret); 121f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return NULL; 122f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 123f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 124f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavativoid alarm_free(alarm_t *alarm) { 125f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (!alarm) 126f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return; 127f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 128f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm_cancel(alarm); 129f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_destroy(&alarm->callback_lock); 130ee2aa45def216a3c4d6a23481fa96f1b02a5de8cZach Johnson osi_free(alarm); 131f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 132f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 133f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavativoid alarm_set(alarm_t *alarm, period_ms_t deadline, alarm_callback_t cb, void *data) { 13471864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson alarm_set_internal(alarm, deadline, cb, data, false); 13571864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson} 13671864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson 13771864f490d4dc31857df0b31924cd62a337e9f1aZach Johnsonvoid alarm_set_periodic(alarm_t *alarm, period_ms_t period, alarm_callback_t cb, void *data) { 13871864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson alarm_set_internal(alarm, period, cb, data, true); 13971864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson} 14071864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson 14171864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson// Runs in exclusion with alarm_cancel and timer_callback. 142e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnsonstatic void alarm_set_internal(alarm_t *alarm, period_ms_t period, alarm_callback_t cb, void *data, bool is_periodic) { 143f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarms != NULL); 144f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarm != NULL); 145f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(cb != NULL); 146f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 147f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_lock(&monitor); 148f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 149f2bf2308e90386754080a4fd7cc2ee7751eeab46Sharvil Nanavati alarm->creation_time = now(); 150e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson alarm->is_periodic = is_periodic; 151e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson alarm->period = period; 152f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm->callback = cb; 153f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm->data = data; 154f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 155952d180f37fa4f8427eaa190b4c78601c18d2ae0Zach Johnson schedule_next_instance(alarm, false); 156f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 157f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_unlock(&monitor); 158f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 159f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 160f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavativoid alarm_cancel(alarm_t *alarm) { 161f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarms != NULL); 162f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarm != NULL); 163f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 164f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_lock(&monitor); 165f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 166f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati bool needs_reschedule = (!list_is_empty(alarms) && list_front(alarms) == alarm); 167f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 168f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati list_remove(alarms, alarm); 169f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm->deadline = 0; 170f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm->callback = NULL; 171f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm->data = NULL; 172f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 173f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (needs_reschedule) 174e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson reschedule_root_alarm(); 175f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 176f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_unlock(&monitor); 177f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 178f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati // If the callback for |alarm| is in progress, wait here until it completes. 179f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_lock(&alarm->callback_lock); 180f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_unlock(&alarm->callback_lock); 181f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 182f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 1830933b4075e16589a073e85d8230677238b29b780Pavlin Radoslavovvoid alarm_cleanup(void) { 184c6a1c261b87f194b298df01f002292d9e937ec75Zach Johnson // If lazy_initialize never ran there is nothing to do 185c6a1c261b87f194b298df01f002292d9e937ec75Zach Johnson if (!alarms) 186c6a1c261b87f194b298df01f002292d9e937ec75Zach Johnson return; 187c6a1c261b87f194b298df01f002292d9e937ec75Zach Johnson 188cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach callback_thread_active = false; 189cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach semaphore_post(alarm_expired); 190cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach thread_free(callback_thread); 191cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach callback_thread = NULL; 192cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach 193cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach semaphore_free(alarm_expired); 194cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach alarm_expired = NULL; 195cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach timer_delete(&timer); 196cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach list_free(alarms); 197cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach alarms = NULL; 198cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach 199cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach pthread_mutex_destroy(&monitor); 200cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach} 201cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach 202f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic bool lazy_initialize(void) { 203f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarms == NULL); 204f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 205f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati pthread_mutex_init(&monitor, NULL); 206f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 207f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarms = list_new(NULL); 208f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (!alarms) { 209db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to allocate alarm list.", __func__); 210f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return false; 211f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 212f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 213518a94e706a6602ad69245b0d760cd40595109ffZach Johnson struct sigevent sigevent; 214518a94e706a6602ad69245b0d760cd40595109ffZach Johnson memset(&sigevent, 0, sizeof(sigevent)); 215518a94e706a6602ad69245b0d760cd40595109ffZach Johnson sigevent.sigev_notify = SIGEV_THREAD; 216518a94e706a6602ad69245b0d760cd40595109ffZach Johnson sigevent.sigev_notify_function = (void (*)(union sigval))timer_callback; 217518a94e706a6602ad69245b0d760cd40595109ffZach Johnson if (timer_create(CLOCK_ID, &sigevent, &timer) == -1) { 218db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to create timer: %s", __func__, strerror(errno)); 219518a94e706a6602ad69245b0d760cd40595109ffZach Johnson return false; 220518a94e706a6602ad69245b0d760cd40595109ffZach Johnson } 221518a94e706a6602ad69245b0d760cd40595109ffZach Johnson 222081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson alarm_expired = semaphore_new(0); 223081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson if (!alarm_expired) { 224db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to create alarm expired semaphore", __func__); 225081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson return false; 226081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson } 227081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 228cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach callback_thread_active = true; 229081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson callback_thread = thread_new("alarm_callbacks"); 230081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson if (!callback_thread) { 231db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to create alarm callback thread.", __func__); 232f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return false; 233f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 234f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 235081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson thread_post(callback_thread, callback_dispatch, NULL); 236f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return true; 237f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 238f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 239f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavatistatic period_ms_t now(void) { 240f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarms != NULL); 241f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 242f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati struct timespec ts; 243f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati if (clock_gettime(CLOCK_ID, &ts) == -1) { 244db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to get current time: %s", __func__, strerror(errno)); 245f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return 0; 246f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 247f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 248f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati return (ts.tv_sec * 1000LL) + (ts.tv_nsec / 1000000LL); 249f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 250f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 25171864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson// Must be called with monitor held 252952d180f37fa4f8427eaa190b4c78601c18d2ae0Zach Johnsonstatic void schedule_next_instance(alarm_t *alarm, bool force_reschedule) { 25371864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson // If the alarm is currently set and it's at the start of the list, 25471864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson // we'll need to re-schedule since we've adjusted the earliest deadline. 25571864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson bool needs_reschedule = (!list_is_empty(alarms) && list_front(alarms) == alarm); 25671864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson if (alarm->callback) 25771864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson list_remove(alarms, alarm); 258f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 259e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson // Calculate the next deadline for this alarm 260e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson period_ms_t just_now = now(); 261f2bf2308e90386754080a4fd7cc2ee7751eeab46Sharvil Nanavati period_ms_t ms_into_period = alarm->is_periodic ? ((just_now - alarm->creation_time) % alarm->period) : 0; 262e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson alarm->deadline = just_now + (alarm->period - ms_into_period); 263f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 26471864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson // Add it into the timer list sorted by deadline (earliest deadline first). 26571864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson if (list_is_empty(alarms) || ((alarm_t *)list_front(alarms))->deadline >= alarm->deadline) 26671864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson list_prepend(alarms, alarm); 26771864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson else 26871864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson for (list_node_t *node = list_begin(alarms); node != list_end(alarms); node = list_next(node)) { 26971864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson list_node_t *next = list_next(node); 27071864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson if (next == list_end(alarms) || ((alarm_t *)list_node(next))->deadline >= alarm->deadline) { 27171864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson list_insert_after(alarms, node, alarm); 27271864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson break; 27371864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson } 27471864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson } 275f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 27671864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson // If the new alarm has the earliest deadline, we need to re-evaluate our schedule. 277952d180f37fa4f8427eaa190b4c78601c18d2ae0Zach Johnson if (force_reschedule || needs_reschedule || (!list_is_empty(alarms) && list_front(alarms) == alarm)) 278e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnson reschedule_root_alarm(); 279f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 280f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 281f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati// NOTE: must be called with monitor lock. 282e2c57aaba4fd0c029a8cb4c519f6ef11f041b4deZach Johnsonstatic void reschedule_root_alarm(void) { 2834be4396c8e4dc4c308219bdf402447a7feefe73ePavlin Radoslavov bool timer_was_set = timer_set; 284f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati assert(alarms != NULL); 285f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 286518a94e706a6602ad69245b0d760cd40595109ffZach Johnson // If used in a zeroed state, disarms the timer 287518a94e706a6602ad69245b0d760cd40595109ffZach Johnson struct itimerspec wakeup_time; 288518a94e706a6602ad69245b0d760cd40595109ffZach Johnson memset(&wakeup_time, 0, sizeof(wakeup_time)); 289f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 290518a94e706a6602ad69245b0d760cd40595109ffZach Johnson if (list_is_empty(alarms)) 291518a94e706a6602ad69245b0d760cd40595109ffZach Johnson goto done; 292f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 293f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati alarm_t *next = list_front(alarms); 294518a94e706a6602ad69245b0d760cd40595109ffZach Johnson int64_t next_expiration = next->deadline - now(); 295518a94e706a6602ad69245b0d760cd40595109ffZach Johnson if (next_expiration < TIMER_INTERVAL_FOR_WAKELOCK_IN_MS) { 296518a94e706a6602ad69245b0d760cd40595109ffZach Johnson if (!timer_set) { 29771864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson int status = bt_os_callouts->acquire_wake_lock(WAKE_LOCK_ID); 29871864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson if (status != BT_STATUS_SUCCESS) { 299db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to acquire wake lock: %d", __func__, status); 300518a94e706a6602ad69245b0d760cd40595109ffZach Johnson goto done; 30171864f490d4dc31857df0b31924cd62a337e9f1aZach Johnson } 302f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 303f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 304f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati wakeup_time.it_value.tv_sec = (next->deadline / 1000); 305f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati wakeup_time.it_value.tv_nsec = (next->deadline % 1000) * 1000000LL; 306f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } else { 307518a94e706a6602ad69245b0d760cd40595109ffZach Johnson if (!bt_os_callouts->set_wake_alarm(next_expiration, true, timer_callback, NULL)) 308db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to set wake alarm for %" PRId64 "ms.", __func__, next_expiration); 309f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 310f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 311518a94e706a6602ad69245b0d760cd40595109ffZach Johnsondone: 312518a94e706a6602ad69245b0d760cd40595109ffZach Johnson timer_set = wakeup_time.it_value.tv_sec != 0 || wakeup_time.it_value.tv_nsec != 0; 3134be4396c8e4dc4c308219bdf402447a7feefe73ePavlin Radoslavov if (timer_was_set && !timer_set) { 314f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati bt_os_callouts->release_wake_lock(WAKE_LOCK_ID); 315f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 316f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 317518a94e706a6602ad69245b0d760cd40595109ffZach Johnson if (timer_settime(timer, TIMER_ABSTIME, &wakeup_time, NULL) == -1) 318db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s unable to set timer: %s", __func__, strerror(errno)); 319081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 320081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // If next expiration was in the past (e.g. short timer that got context switched) 321081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // then the timer might have diarmed itself. Detect this case and work around it 322081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // by manually signalling the |alarm_expired| semaphore. 323081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // 324081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // It is possible that the timer was actually super short (a few milliseconds) 325081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // and the timer expired normally before we called |timer_gettime|. Worst case, 326081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // |alarm_expired| is signaled twice for that alarm. Nothing bad should happen in 327081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // that case though since the callback dispatch function checks to make sure the 328081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // timer at the head of the list actually expired. 329081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson if (timer_set) { 330081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson struct itimerspec time_to_expire; 331081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson timer_gettime(timer, &time_to_expire); 332081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson if (time_to_expire.it_value.tv_sec == 0 && time_to_expire.it_value.tv_nsec == 0) { 333db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_ERROR(LOG_TAG, "%s alarm expiration too close for posix timers, switching to guns", __func__); 334081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson semaphore_post(alarm_expired); 335f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 336081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson } 337081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson} 338081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 339081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson// Callback function for wake alarms and our posix timer 340081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnsonstatic void timer_callback(UNUSED_ATTR void *ptr) { 341081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson semaphore_post(alarm_expired); 342081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson} 343f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 344081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson// Function running on |callback_thread| that dispatches alarm callbacks upon 345081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson// alarm expiration, which is signaled using |alarm_expired|. 346081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnsonstatic void callback_dispatch(UNUSED_ATTR void *context) { 347081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson while (true) { 348081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson semaphore_wait(alarm_expired); 349cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach if (!callback_thread_active) 350cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach break; 351081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 352cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach pthread_mutex_lock(&monitor); 353081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson alarm_t *alarm; 354081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 355081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // Take into account that the alarm may get cancelled before we get to it. 356081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // We're done here if there are no alarms or the alarm at the front is in 357081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // the future. Release the monitor lock and exit right away since there's 358081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // nothing left to do. 359081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson if (list_is_empty(alarms) || (alarm = list_front(alarms))->deadline > now()) { 360081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson reschedule_root_alarm(); 361081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson pthread_mutex_unlock(&monitor); 362081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson continue; 363f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 364f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 365081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson list_remove(alarms, alarm); 366081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 367081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson alarm_callback_t callback = alarm->callback; 368081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson void *data = alarm->data; 369081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 370081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson if (alarm->is_periodic) { 371952d180f37fa4f8427eaa190b4c78601c18d2ae0Zach Johnson schedule_next_instance(alarm, true); 372081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson } else { 373081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson reschedule_root_alarm(); 374081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 375081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson alarm->deadline = 0; 376081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson alarm->callback = NULL; 377081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson alarm->data = NULL; 378f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 379f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati 380081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson // Downgrade lock. 381081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson pthread_mutex_lock(&alarm->callback_lock); 382081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson pthread_mutex_unlock(&monitor); 383081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 384081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson callback(data); 385081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson 386081e4b67b44a5fd397c2d79a5566e11ae52d4acaZach Johnson pthread_mutex_unlock(&alarm->callback_lock); 387f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati } 388cae219fe70124f1fc39cd7a78c239c4870422d5dAndre Eisenbach 389db554581079863974af8e1289646f5deea6fc044Marie Janssen LOG_DEBUG(LOG_TAG, "%s Callback thread exited", __func__); 390f0e7c8b895c61104ce962b7c5e3705a32943d711Sharvil Nanavati} 391