1 /* 2 * Copyright (C) 2014 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 #ifndef ANDROID_AUDIO_FAST_THREAD_DUMP_STATE_H 18 #define ANDROID_AUDIO_FAST_THREAD_DUMP_STATE_H 19 20 #include "Configuration.h" 21 #include "FastThreadState.h" 22 23 namespace android { 24 25 // The FastThreadDumpState keeps a cache of FastThread statistics that can be logged by dumpsys. 26 // Each individual native word-sized field is accessed atomically. But the 27 // overall structure is non-atomic, that is there may be an inconsistency between fields. 28 // No barriers or locks are used for either writing or reading. 29 // Only POD types are permitted, and the contents shouldn't be trusted (i.e. do range checks). 30 // It has a different lifetime than the FastThread, and so it can't be a member of FastThread. 31 struct FastThreadDumpState { 32 FastThreadDumpState(); 33 /*virtual*/ ~FastThreadDumpState(); 34 35 FastThreadState::Command mCommand; // current command 36 uint32_t mUnderruns; // total number of underruns 37 uint32_t mOverruns; // total number of overruns 38 struct timespec mMeasuredWarmupTs; // measured warmup time 39 uint32_t mWarmupCycles; // number of loop cycles required to warmup 40 41 #ifdef FAST_THREAD_STATISTICS 42 // Recently collected samples of per-cycle monotonic time, thread CPU time, and CPU frequency. 43 // kSamplingN is max size of sampling frame (statistics), and must be a power of 2 <= 0x8000. 44 // The sample arrays are virtually allocated based on this compile-time constant, 45 // but are only initialized and used based on the runtime parameter mSamplingN. 46 static const uint32_t kSamplingN = 0x8000; 47 // Compile-time constant for a "low RAM device", must be a power of 2 <= kSamplingN. 48 // This value was chosen such that each array uses 1 small page (4 Kbytes). 49 static const uint32_t kSamplingNforLowRamDevice = 0x400; 50 // Corresponding runtime maximum size of sample arrays, must be a power of 2 <= kSamplingN. 51 uint32_t mSamplingN; 52 // The bounds define the interval of valid samples, and are represented as follows: 53 // newest open (excluded) endpoint = lower 16 bits of bounds, modulo N 54 // oldest closed (included) endpoint = upper 16 bits of bounds, modulo N 55 // Number of valid samples is newest - oldest. 56 uint32_t mBounds; // bounds for mMonotonicNs, mThreadCpuNs, and mCpukHz 57 // The elements in the *Ns arrays are in units of nanoseconds <= 3999999999. 58 uint32_t mMonotonicNs[kSamplingN]; // delta monotonic (wall clock) time 59 uint32_t mLoadNs[kSamplingN]; // delta CPU load in time 60 #ifdef CPU_FREQUENCY_STATISTICS 61 uint32_t mCpukHz[kSamplingN]; // absolute CPU clock frequency in kHz, bits 0-3 are CPU# 62 #endif 63 64 // Increase sampling window after construction, must be a power of 2 <= kSamplingN 65 void increaseSamplingN(uint32_t samplingN); 66 #endif 67 68 }; // struct FastThreadDumpState 69 70 } // android 71 72 #endif // ANDROID_AUDIO_FAST_THREAD_DUMP_STATE_H 73