1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "powerhal-libperfmgr"
18 #define ATRACE_TAG (ATRACE_TAG_POWER | ATRACE_TAG_HAL)
19 
20 #include <array>
21 #include <memory>
22 
23 #include <fcntl.h>
24 #include <poll.h>
25 #include <sys/eventfd.h>
26 #include <time.h>
27 #include <unistd.h>
28 
29 #include <android-base/properties.h>
30 #include <utils/Log.h>
31 #include <utils/Trace.h>
32 
33 #include "InteractionHandler.h"
34 
35 #define MAX_LENGTH 64
36 
37 #define MSINSEC 1000L
38 #define NSINMS 1000000L
39 
40 namespace aidl {
41 namespace google {
42 namespace hardware {
43 namespace power {
44 namespace impl {
45 namespace pixel {
46 
47 namespace {
48 
49 static const bool kDisplayIdleSupport =
50         ::android::base::GetBoolProperty("vendor.powerhal.disp.idle_support", true);
51 static const std::array<const char *, 2> kDispIdlePath = {"/sys/class/drm/card0/device/idle_state",
52                                                           "/sys/class/graphics/fb0/idle_state"};
53 static const uint32_t kWaitMs =
54         ::android::base::GetUintProperty("vendor.powerhal.disp.idle_wait", /*default*/ 100U);
55 static const uint32_t kMinDurationMs =
56         ::android::base::GetUintProperty("vendor.powerhal.interaction.min", /*default*/ 1400U);
57 static const uint32_t kMaxDurationMs =
58         ::android::base::GetUintProperty("vendor.powerhal.interaction.max", /*default*/ 5650U);
59 static const uint32_t kDurationOffsetMs =
60         ::android::base::GetUintProperty("vendor.powerhal.interaction.offset", /*default*/ 650U);
61 
CalcTimespecDiffMs(struct timespec start,struct timespec end)62 static size_t CalcTimespecDiffMs(struct timespec start, struct timespec end) {
63     size_t diff_in_ms = 0;
64     diff_in_ms += (end.tv_sec - start.tv_sec) * MSINSEC;
65     diff_in_ms += (end.tv_nsec - start.tv_nsec) / NSINMS;
66     return diff_in_ms;
67 }
68 
FbIdleOpen(void)69 static int FbIdleOpen(void) {
70     int fd;
71     for (const auto &path : kDispIdlePath) {
72         fd = open(path, O_RDONLY);
73         if (fd >= 0)
74             return fd;
75     }
76     ALOGE("Unable to open fb idle state path (%d)", errno);
77     return -1;
78 }
79 
80 }  // namespace
81 
InteractionHandler(std::shared_ptr<HintManager> const & hint_manager)82 InteractionHandler::InteractionHandler(std::shared_ptr<HintManager> const &hint_manager)
83     : mState(INTERACTION_STATE_UNINITIALIZED),
84       mDurationMs(0),
85       mHintManager(hint_manager) {}
86 
~InteractionHandler()87 InteractionHandler::~InteractionHandler() {
88     Exit();
89 }
90 
Init()91 bool InteractionHandler::Init() {
92     std::lock_guard<std::mutex> lk(mLock);
93 
94     if (mState != INTERACTION_STATE_UNINITIALIZED)
95         return true;
96 
97     int fd = FbIdleOpen();
98     if (fd < 0)
99         return false;
100     mIdleFd = fd;
101 
102     mEventFd = eventfd(0, EFD_NONBLOCK);
103     if (mEventFd < 0) {
104         ALOGE("Unable to create event fd (%d)", errno);
105         close(mIdleFd);
106         return false;
107     }
108 
109     mState = INTERACTION_STATE_IDLE;
110     mThread = std::unique_ptr<std::thread>(new std::thread(&InteractionHandler::Routine, this));
111 
112     return true;
113 }
114 
Exit()115 void InteractionHandler::Exit() {
116     std::unique_lock<std::mutex> lk(mLock);
117     if (mState == INTERACTION_STATE_UNINITIALIZED)
118         return;
119 
120     AbortWaitLocked();
121     mState = INTERACTION_STATE_UNINITIALIZED;
122     lk.unlock();
123 
124     mCond.notify_all();
125     mThread->join();
126 
127     close(mEventFd);
128     close(mIdleFd);
129 }
130 
PerfLock()131 void InteractionHandler::PerfLock() {
132     ALOGV("%s: acquiring perf lock", __func__);
133     if (!mHintManager->DoHint("INTERACTION")) {
134         ALOGE("%s: do hint INTERACTION failed", __func__);
135     }
136 }
137 
PerfRel()138 void InteractionHandler::PerfRel() {
139     ALOGV("%s: releasing perf lock", __func__);
140     if (!mHintManager->EndHint("INTERACTION")) {
141         ALOGE("%s: end hint INTERACTION failed", __func__);
142     }
143 }
144 
Acquire(int32_t duration)145 void InteractionHandler::Acquire(int32_t duration) {
146     ATRACE_CALL();
147 
148     std::lock_guard<std::mutex> lk(mLock);
149 
150     int inputDuration = duration + kDurationOffsetMs;
151     int finalDuration;
152     if (inputDuration > kMaxDurationMs)
153         finalDuration = kMaxDurationMs;
154     else if (inputDuration > kMinDurationMs)
155         finalDuration = inputDuration;
156     else
157         finalDuration = kMinDurationMs;
158 
159     // Fallback to do boost directly
160     // 1) override property is set OR
161     // 2) InteractionHandler not initialized
162     if (!kDisplayIdleSupport || mState == INTERACTION_STATE_UNINITIALIZED) {
163         mHintManager->DoHint("INTERACTION", std::chrono::milliseconds(finalDuration));
164         return;
165     }
166 
167     struct timespec cur_timespec;
168     clock_gettime(CLOCK_MONOTONIC, &cur_timespec);
169     if (mState != INTERACTION_STATE_IDLE && finalDuration <= mDurationMs) {
170         size_t elapsed_time = CalcTimespecDiffMs(mLastTimespec, cur_timespec);
171         // don't hint if previous hint's duration covers this hint's duration
172         if (elapsed_time <= (mDurationMs - finalDuration)) {
173             ALOGV("%s: Previous duration (%d) cover this (%d) elapsed: %lld", __func__,
174                   static_cast<int>(mDurationMs), static_cast<int>(finalDuration),
175                   static_cast<long long>(elapsed_time));
176             return;
177         }
178     }
179     mLastTimespec = cur_timespec;
180     mDurationMs = finalDuration;
181 
182     ALOGV("%s: input: %d final duration: %d", __func__, duration, finalDuration);
183 
184     if (mState == INTERACTION_STATE_WAITING)
185         AbortWaitLocked();
186     else if (mState == INTERACTION_STATE_IDLE)
187         PerfLock();
188 
189     mState = INTERACTION_STATE_INTERACTION;
190     mCond.notify_one();
191 }
192 
Release()193 void InteractionHandler::Release() {
194     std::lock_guard<std::mutex> lk(mLock);
195     if (mState == INTERACTION_STATE_WAITING) {
196         ATRACE_CALL();
197         PerfRel();
198         mState = INTERACTION_STATE_IDLE;
199     } else {
200         // clear any wait aborts pending in event fd
201         uint64_t val;
202         ssize_t ret = read(mEventFd, &val, sizeof(val));
203 
204         ALOGW_IF(ret < 0, "%s: failed to clear eventfd (%zd, %d)", __func__, ret, errno);
205     }
206 }
207 
208 // should be called while locked
AbortWaitLocked()209 void InteractionHandler::AbortWaitLocked() {
210     uint64_t val = 1;
211     ssize_t ret = write(mEventFd, &val, sizeof(val));
212     if (ret != sizeof(val))
213         ALOGW("Unable to write to event fd (%zd)", ret);
214 }
215 
WaitForIdle(int32_t wait_ms,int32_t timeout_ms)216 void InteractionHandler::WaitForIdle(int32_t wait_ms, int32_t timeout_ms) {
217     char data[MAX_LENGTH];
218     ssize_t ret;
219     struct pollfd pfd[2];
220 
221     ATRACE_CALL();
222 
223     ALOGV("%s: wait:%d timeout:%d", __func__, wait_ms, timeout_ms);
224 
225     pfd[0].fd = mEventFd;
226     pfd[0].events = POLLIN;
227     pfd[1].fd = mIdleFd;
228     pfd[1].events = POLLPRI | POLLERR;
229 
230     ret = poll(pfd, 1, wait_ms);
231     if (ret > 0) {
232         ALOGV("%s: wait aborted", __func__);
233         return;
234     } else if (ret < 0) {
235         ALOGE("%s: error in poll while waiting", __func__);
236         return;
237     }
238 
239     ret = pread(mIdleFd, data, sizeof(data), 0);
240     if (!ret) {
241         ALOGE("%s: Unexpected EOF!", __func__);
242         return;
243     }
244 
245     if (!strncmp(data, "idle", 4)) {
246         ALOGV("%s: already idle", __func__);
247         return;
248     }
249 
250     ret = poll(pfd, 2, timeout_ms);
251     if (ret < 0)
252         ALOGE("%s: Error on waiting for idle (%zd)", __func__, ret);
253     else if (ret == 0)
254         ALOGV("%s: timed out waiting for idle", __func__);
255     else if (pfd[0].revents)
256         ALOGV("%s: wait for idle aborted", __func__);
257     else if (pfd[1].revents)
258         ALOGV("%s: idle detected", __func__);
259 }
260 
Routine()261 void InteractionHandler::Routine() {
262     pthread_setname_np(pthread_self(), "DispIdle");
263     std::unique_lock<std::mutex> lk(mLock, std::defer_lock);
264 
265     while (true) {
266         lk.lock();
267         mCond.wait(lk, [&] { return mState != INTERACTION_STATE_IDLE; });
268         if (mState == INTERACTION_STATE_UNINITIALIZED)
269             return;
270         mState = INTERACTION_STATE_WAITING;
271         lk.unlock();
272 
273         WaitForIdle(kWaitMs, mDurationMs);
274         Release();
275     }
276 }
277 
278 }  // namespace pixel
279 }  // namespace impl
280 }  // namespace power
281 }  // namespace hardware
282 }  // namespace google
283 }  // namespace aidl
284