Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1 | // Copyright 2007-2008 the V8 project authors. All rights reserved. |
| 2 | // Redistribution and use in source and binary forms, with or without |
| 3 | // modification, are permitted provided that the following conditions are |
| 4 | // met: |
| 5 | // |
| 6 | // * Redistributions of source code must retain the above copyright |
| 7 | // notice, this list of conditions and the following disclaimer. |
| 8 | // * Redistributions in binary form must reproduce the above |
| 9 | // copyright notice, this list of conditions and the following |
| 10 | // disclaimer in the documentation and/or other materials provided |
| 11 | // with the distribution. |
| 12 | // * Neither the name of Google Inc. nor the names of its |
| 13 | // contributors may be used to endorse or promote products derived |
| 14 | // from this software without specific prior written permission. |
| 15 | // |
| 16 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 17 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 18 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 19 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 20 | // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 21 | // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 22 | // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 23 | // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 24 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 25 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 26 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | |
| 28 | #ifndef V8_COUNTERS_H_ |
| 29 | #define V8_COUNTERS_H_ |
| 30 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame^] | 31 | #include "../include/v8.h" |
| 32 | #include "allocation.h" |
| 33 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 34 | namespace v8 { |
| 35 | namespace internal { |
| 36 | |
| 37 | // StatsCounters is an interface for plugging into external |
| 38 | // counters for monitoring. Counters can be looked up and |
| 39 | // manipulated by name. |
| 40 | |
| 41 | class StatsTable : public AllStatic { |
| 42 | public: |
| 43 | // Register an application-defined function where |
| 44 | // counters can be looked up. |
| 45 | static void SetCounterFunction(CounterLookupCallback f) { |
| 46 | lookup_function_ = f; |
| 47 | } |
| 48 | |
| 49 | // Register an application-defined function to create |
| 50 | // a histogram for passing to the AddHistogramSample function |
| 51 | static void SetCreateHistogramFunction(CreateHistogramCallback f) { |
| 52 | create_histogram_function_ = f; |
| 53 | } |
| 54 | |
| 55 | // Register an application-defined function to add a sample |
| 56 | // to a histogram created with CreateHistogram function |
| 57 | static void SetAddHistogramSampleFunction(AddHistogramSampleCallback f) { |
| 58 | add_histogram_sample_function_ = f; |
| 59 | } |
| 60 | |
| 61 | static bool HasCounterFunction() { |
| 62 | return lookup_function_ != NULL; |
| 63 | } |
| 64 | |
| 65 | // Lookup the location of a counter by name. If the lookup |
| 66 | // is successful, returns a non-NULL pointer for writing the |
| 67 | // value of the counter. Each thread calling this function |
| 68 | // may receive a different location to store it's counter. |
| 69 | // The return value must not be cached and re-used across |
| 70 | // threads, although a single thread is free to cache it. |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 71 | static int* FindLocation(const char* name) { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 72 | if (!lookup_function_) return NULL; |
| 73 | return lookup_function_(name); |
| 74 | } |
| 75 | |
| 76 | // Create a histogram by name. If the create is successful, |
| 77 | // returns a non-NULL pointer for use with AddHistogramSample |
| 78 | // function. min and max define the expected minimum and maximum |
| 79 | // sample values. buckets is the maximum number of buckets |
| 80 | // that the samples will be grouped into. |
| 81 | static void* CreateHistogram(const char* name, |
| 82 | int min, |
| 83 | int max, |
| 84 | size_t buckets) { |
| 85 | if (!create_histogram_function_) return NULL; |
| 86 | return create_histogram_function_(name, min, max, buckets); |
| 87 | } |
| 88 | |
| 89 | // Add a sample to a histogram created with the CreateHistogram |
| 90 | // function. |
| 91 | static void AddHistogramSample(void* histogram, int sample) { |
| 92 | if (!add_histogram_sample_function_) return; |
| 93 | return add_histogram_sample_function_(histogram, sample); |
| 94 | } |
| 95 | |
| 96 | private: |
| 97 | static CounterLookupCallback lookup_function_; |
| 98 | static CreateHistogramCallback create_histogram_function_; |
| 99 | static AddHistogramSampleCallback add_histogram_sample_function_; |
| 100 | }; |
| 101 | |
| 102 | // StatsCounters are dynamically created values which can be tracked in |
| 103 | // the StatsTable. They are designed to be lightweight to create and |
| 104 | // easy to use. |
| 105 | // |
| 106 | // Internally, a counter represents a value in a row of a StatsTable. |
| 107 | // The row has a 32bit value for each process/thread in the table and also |
| 108 | // a name (stored in the table metadata). Since the storage location can be |
| 109 | // thread-specific, this class cannot be shared across threads. |
| 110 | // |
| 111 | // This class is designed to be POD initialized. It will be registered with |
| 112 | // the counter system on first use. For example: |
| 113 | // StatsCounter c = { "c:myctr", NULL, false }; |
| 114 | struct StatsCounter { |
| 115 | const char* name_; |
| 116 | int* ptr_; |
| 117 | bool lookup_done_; |
| 118 | |
| 119 | // Sets the counter to a specific value. |
| 120 | void Set(int value) { |
| 121 | int* loc = GetPtr(); |
| 122 | if (loc) *loc = value; |
| 123 | } |
| 124 | |
| 125 | // Increments the counter. |
| 126 | void Increment() { |
| 127 | int* loc = GetPtr(); |
| 128 | if (loc) (*loc)++; |
| 129 | } |
| 130 | |
| 131 | void Increment(int value) { |
| 132 | int* loc = GetPtr(); |
| 133 | if (loc) |
| 134 | (*loc) += value; |
| 135 | } |
| 136 | |
| 137 | // Decrements the counter. |
| 138 | void Decrement() { |
| 139 | int* loc = GetPtr(); |
| 140 | if (loc) (*loc)--; |
| 141 | } |
| 142 | |
| 143 | void Decrement(int value) { |
| 144 | int* loc = GetPtr(); |
| 145 | if (loc) (*loc) -= value; |
| 146 | } |
| 147 | |
| 148 | // Is this counter enabled? |
| 149 | // Returns false if table is full. |
| 150 | bool Enabled() { |
| 151 | return GetPtr() != NULL; |
| 152 | } |
| 153 | |
| 154 | // Get the internal pointer to the counter. This is used |
| 155 | // by the code generator to emit code that manipulates a |
| 156 | // given counter without calling the runtime system. |
| 157 | int* GetInternalPointer() { |
| 158 | int* loc = GetPtr(); |
| 159 | ASSERT(loc != NULL); |
| 160 | return loc; |
| 161 | } |
| 162 | |
| 163 | protected: |
| 164 | // Returns the cached address of this counter location. |
| 165 | int* GetPtr() { |
| 166 | if (lookup_done_) |
| 167 | return ptr_; |
| 168 | lookup_done_ = true; |
| 169 | ptr_ = StatsTable::FindLocation(name_); |
| 170 | return ptr_; |
| 171 | } |
| 172 | }; |
| 173 | |
| 174 | // StatsCounterTimer t = { { L"t:foo", NULL, false }, 0, 0 }; |
| 175 | struct StatsCounterTimer { |
| 176 | StatsCounter counter_; |
| 177 | |
| 178 | int64_t start_time_; |
| 179 | int64_t stop_time_; |
| 180 | |
| 181 | // Start the timer. |
| 182 | void Start(); |
| 183 | |
| 184 | // Stop the timer and record the results. |
| 185 | void Stop(); |
| 186 | |
| 187 | // Returns true if the timer is running. |
| 188 | bool Running() { |
| 189 | return counter_.Enabled() && start_time_ != 0 && stop_time_ == 0; |
| 190 | } |
| 191 | }; |
| 192 | |
| 193 | // A HistogramTimer allows distributions of results to be created |
| 194 | // HistogramTimer t = { L"foo", NULL, false, 0, 0 }; |
| 195 | struct HistogramTimer { |
| 196 | const char* name_; |
| 197 | void* histogram_; |
| 198 | bool lookup_done_; |
| 199 | |
| 200 | int64_t start_time_; |
| 201 | int64_t stop_time_; |
| 202 | |
| 203 | // Start the timer. |
| 204 | void Start(); |
| 205 | |
| 206 | // Stop the timer and record the results. |
| 207 | void Stop(); |
| 208 | |
| 209 | // Returns true if the timer is running. |
| 210 | bool Running() { |
| 211 | return (histogram_ != NULL) && (start_time_ != 0) && (stop_time_ == 0); |
| 212 | } |
| 213 | |
| 214 | protected: |
| 215 | // Returns the handle to the histogram. |
| 216 | void* GetHistogram() { |
| 217 | if (!lookup_done_) { |
| 218 | lookup_done_ = true; |
| 219 | histogram_ = StatsTable::CreateHistogram(name_, 0, 10000, 50); |
| 220 | } |
| 221 | return histogram_; |
| 222 | } |
| 223 | }; |
| 224 | |
| 225 | // Helper class for scoping a HistogramTimer. |
| 226 | class HistogramTimerScope BASE_EMBEDDED { |
| 227 | public: |
| 228 | explicit HistogramTimerScope(HistogramTimer* timer) : |
| 229 | timer_(timer) { |
| 230 | timer_->Start(); |
| 231 | } |
| 232 | ~HistogramTimerScope() { |
| 233 | timer_->Stop(); |
| 234 | } |
| 235 | private: |
| 236 | HistogramTimer* timer_; |
| 237 | }; |
| 238 | |
| 239 | |
| 240 | } } // namespace v8::internal |
| 241 | |
| 242 | #endif // V8_COUNTERS_H_ |