mozglue/baseprofiler/core/PageInformation.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef PageInformation_h
   8 #define PageInformation_h
   9
  10 #include "mozilla/Atomics.h"
  11 #include "mozilla/Maybe.h"
  12 #include "mozilla/MemoryReporting.h"
  13
  14 #include <string>
  15
  16 namespace mozilla {
  17 namespace baseprofiler {
  18
  19 class SpliceableJSONWriter;
  20
  21 // This class contains information that's relevant to a single page only
  22 // while the page information is important and registered with the profiler,
  23 // but regardless of whether the profiler is running. All accesses to it are
  24 // protected by the profiler state lock.
  25 // When the page gets unregistered, we keep the profiler buffer position
  26 // to determine if we are still using this page. If not, we unregister
  27 // it in the next page registration.
  28 class PageInformation final {
  29  public:
  30   PageInformation(uint64_t aTabID, uint64_t aInnerWindowID,
  31                   const std::string& aUrl, uint64_t aEmbedderInnerWindowID);
  32
  33   // Using hand-rolled ref-counting, because RefCounted.h macros don't produce
  34   // the same code between mozglue and libxul, see bug 1536656.
  35   MFBT_API void AddRef() const { ++mRefCnt; }
  36   MFBT_API void Release() const {
  37     MOZ_ASSERT(int32_t(mRefCnt) > 0);
  38     if (--mRefCnt) {
  39       delete this;
  40     }
  41   }
  42
  43   size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;
  44   bool Equals(PageInformation* aOtherPageInfo) const;
  45   void StreamJSON(SpliceableJSONWriter& aWriter) const;
  46
  47   uint64_t InnerWindowID() const { return mInnerWindowID; }
  48   uint64_t TabID() const { return mTabID; }
  49   const std::string& Url() const { return mUrl; }
  50   uint64_t EmbedderInnerWindowID() const { return mEmbedderInnerWindowID; }
  51
  52   Maybe<uint64_t> BufferPositionWhenUnregistered() const {
  53     return mBufferPositionWhenUnregistered;
  54   }
  55
  56   void NotifyUnregistered(uint64_t aBufferPosition) {
  57     mBufferPositionWhenUnregistered = Some(aBufferPosition);
  58   }
  59
  60  private:
  61   const uint64_t mTabID;
  62   const uint64_t mInnerWindowID;
  63   const std::string mUrl;
  64   const uint64_t mEmbedderInnerWindowID;
  65
  66   // Holds the buffer position when page is unregistered.
  67   // It's used to determine if we still use this page in the profiler or
  68   // not.
  69   Maybe<uint64_t> mBufferPositionWhenUnregistered;
  70
  71   mutable Atomic<int32_t, MemoryOrdering::ReleaseAcquire> mRefCnt;
  72 };
  73
  74 }  // namespace baseprofiler
  75 }  // namespace mozilla
  76
  77 #endif  // PageInformation_h