1 /* 2 * Copyright (C) 2017 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 specic language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_LIBPERFMGR_NODE_H_ 18 #define ANDROID_LIBPERFMGR_NODE_H_ 19 20 #include <cstddef> 21 #include <string> 22 #include <vector> 23 24 #include <android-base/unique_fd.h> 25 26 #include "perfmgr/RequestGroup.h" 27 28 namespace android { 29 namespace perfmgr { 30 31 // The Node class provides an interface for adding and cancelling powerhint 32 // requests, as well as checking the next time that an in-progress powerhint 33 // request will expire. There are additional methods for getting the Node’s name 34 // and the index of a value, which may be used for initialization, debugging, 35 // and request management. The core of the Node class is a vector of 36 // RequestGroups named req_sorted_, which is used to track the in-progress 37 // requests on the node. Each entry in the vector corresponds to a possible 38 // value for the node, in priority order. For example, the first entry in the 39 // vector for the cpu0 cluster represents the in-progress requests to boost the 40 // cluster’s frequency to the highest available value. The next entry represents 41 // the in-progress requests to boost the cluster’s frequency to the next highest 42 // value. For each value, there may be multiple requests because different 43 // powerhints may request the same value, and the requests may have different 44 // expiration times. All of the in-progress powerhints for a given value are 45 // collected in a RequestGroup. Node class is not thread safe so it needs 46 // protection from caller e.g. NodeLooperThread. 47 class Node { 48 public: ~Node()49 virtual ~Node() {} 50 51 // Return true if successfully add a request 52 bool AddRequest(std::size_t value_index, const std::string& hint_type, 53 ReqTime end_time); 54 55 // Return true if successfully remove a request 56 bool RemoveRequest(const std::string& hint_type); 57 58 // Return the nearest expire time of active requests; return 59 // std::chrono::milliseconds::max() if no active request on Node; update 60 // node's controlled file node value and the current value index based on 61 // active request. 62 virtual std::chrono::milliseconds Update(bool log_error) = 0; 63 64 const std::string& GetName() const; 65 const std::string& GetPath() const; 66 std::vector<std::string> GetValues() const; 67 std::size_t GetDefaultIndex() const; 68 bool GetResetOnInit() const; 69 bool GetValueIndex(const std::string& value, std::size_t* index) const; 70 virtual void DumpToFd(int fd) const = 0; 71 72 protected: 73 Node(std::string name, std::string node_path, 74 std::vector<RequestGroup> req_sorted, std::size_t default_val_index, 75 bool reset_on_init); 76 Node(const Node& other) = delete; 77 Node& operator=(Node const&) = delete; 78 79 const std::string name_; 80 const std::string node_path_; 81 // request vector, one entry per possible value, sorted by priority 82 std::vector<RequestGroup> req_sorted_; 83 const std::size_t default_val_index_; 84 const bool reset_on_init_; 85 std::size_t current_val_index_; 86 }; 87 88 } // namespace perfmgr 89 } // namespace android 90 91 #endif // ANDROID_LIBPERFMGR_NODE_H_ 92