| // Copyright 2007-2008 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #ifndef V8_COUNTERS_H_ |
| #define V8_COUNTERS_H_ |
| |
| #include <wchar.h> |
| |
| namespace v8 { namespace internal { |
| |
| // StatsCounters is an interface for plugging into external |
| // counters for monitoring. Counters can be looked up and |
| // manipulated by name. |
| |
| class StatsTable : public AllStatic { |
| public: |
| // Register an application-defined function where |
| // counters can be looked up. |
| static void SetCounterFunction(CounterLookupCallback f) { |
| lookup_function_ = f; |
| } |
| |
| static bool HasCounterFunction() { |
| return lookup_function_ != NULL; |
| } |
| |
| // Lookup the location of a counter by name. If the lookup |
| // is successful, returns a non-NULL pointer for writing the |
| // value of the counter. Each thread calling this function |
| // may receive a different location to store it's counter. |
| // The return value must not be cached and re-used across |
| // threads, although a single thread is free to cache it. |
| static int *FindLocation(const wchar_t* name) { |
| if (!lookup_function_) return NULL; |
| return lookup_function_(name); |
| } |
| |
| private: |
| static CounterLookupCallback lookup_function_; |
| }; |
| |
| // StatsCounters are dynamically created values which can be tracked in |
| // the StatsTable. They are designed to be lightweight to create and |
| // easy to use. |
| // |
| // Internally, a counter represents a value in a row of a StatsTable. |
| // The row has a 32bit value for each process/thread in the table and also |
| // a name (stored in the table metadata). Since the storage location can be |
| // thread-specific, this class cannot be shared across threads. |
| // |
| // This class is designed to be POD initialized. It will be registered with |
| // the counter system on first use. For example: |
| // StatsCounter c = { L"c:myctr", NULL, false }; |
| struct StatsCounter { |
| const wchar_t* name_; |
| int* ptr_; |
| bool lookup_done_; |
| |
| // Sets the counter to a specific value. |
| void Set(int value) { |
| int* loc = GetPtr(); |
| if (loc) *loc = value; |
| } |
| |
| // Increments the counter. |
| void Increment() { |
| int* loc = GetPtr(); |
| if (loc) (*loc)++; |
| } |
| |
| void Increment(int value) { |
| int* loc = GetPtr(); |
| if (loc) |
| (*loc) += value; |
| } |
| |
| // Decrements the counter. |
| void Decrement() { |
| int* loc = GetPtr(); |
| if (loc) (*loc)--; |
| } |
| |
| void Decrement(int value) { |
| int* loc = GetPtr(); |
| if (loc) (*loc) -= value; |
| } |
| |
| // Is this counter enabled? |
| // Returns false if table is full. |
| bool Enabled() { |
| return GetPtr() != NULL; |
| } |
| |
| // Get the internal pointer to the counter. This is used |
| // by the code generator to emit code that manipulates a |
| // given counter without calling the runtime system. |
| int* GetInternalPointer() { |
| int* loc = GetPtr(); |
| ASSERT(loc != NULL); |
| return loc; |
| } |
| |
| protected: |
| // Returns the cached address of this counter location. |
| int* GetPtr() { |
| if (lookup_done_) |
| return ptr_; |
| lookup_done_ = true; |
| ptr_ = StatsTable::FindLocation(name_); |
| return ptr_; |
| } |
| }; |
| |
| // StatsCounterTimer t = { { L"t:foo", NULL, false }, 0, 0 }; |
| struct StatsCounterTimer { |
| StatsCounter counter_; |
| |
| int64_t start_time_; |
| int64_t stop_time_; |
| |
| // Start the timer. |
| void Start(); |
| |
| // Stop the timer and record the results. |
| void Stop(); |
| |
| // Returns true if the timer is running. |
| bool Running() { |
| return counter_.Enabled() && start_time_ != 0 && stop_time_ == 0; |
| } |
| }; |
| |
| // A StatsRate is a combination of both a timer and a counter so that |
| // several statistics can be produced: |
| // min, max, avg, count, total |
| // |
| // For example: |
| // StatsCounter c = { { { L"t:myrate", NULL, false }, 0, 0 }, |
| // { L"c:myrate", NULL, false } }; |
| struct StatsRate { |
| StatsCounterTimer timer_; |
| StatsCounter counter_; |
| |
| // Starts the rate timer. |
| void Start() { |
| timer_.Start(); |
| } |
| |
| // Stops the rate and records the time. |
| void Stop() { |
| if (timer_.Running()) { |
| timer_.Stop(); |
| counter_.Increment(); |
| } |
| } |
| }; |
| |
| |
| // Helper class for scoping a rate. |
| class StatsRateScope BASE_EMBEDDED { |
| public: |
| explicit StatsRateScope(StatsRate* rate) : |
| rate_(rate) { |
| rate_->Start(); |
| } |
| ~StatsRateScope() { |
| rate_->Stop(); |
| } |
| private: |
| StatsRate* rate_; |
| }; |
| |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_COUNTERS_H_ |