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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
commit | 0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch) | |
tree | a31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /image/DecodePool.h | |
parent | Initial commit. (diff) | |
download | firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.tar.xz firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.zip |
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'image/DecodePool.h')
-rw-r--r-- | image/DecodePool.h | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/image/DecodePool.h b/image/DecodePool.h new file mode 100644 index 0000000000..6b25aadf17 --- /dev/null +++ b/image/DecodePool.h @@ -0,0 +1,108 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/** + * DecodePool manages the threads used for decoding raster images. + */ + +#ifndef mozilla_image_DecodePool_h +#define mozilla_image_DecodePool_h + +#include "mozilla/Mutex.h" +#include "mozilla/StaticPtr.h" +#include "nsCOMArray.h" +#include "nsCOMPtr.h" +#include "nsIEventTarget.h" +#include "nsIObserver.h" +#include "mozilla/RefPtr.h" +#include "nsStringFwd.h" + +class nsIThread; +class nsIThreadPool; + +namespace mozilla { +namespace image { + +class Decoder; +class DecodePoolImpl; +class IDecodingTask; + +/** + * DecodePool is a singleton class that manages decoding of raster images. It + * owns a pool of image decoding threads that are used for asynchronous + * decoding. + * + * DecodePool allows callers to run a decoder, handling management of the + * decoder's lifecycle and whether it executes on the main thread, + * off-main-thread in the image decoding thread pool, or on some combination of + * the two. + */ +class DecodePool final : public nsIObserver { + public: + NS_DECL_THREADSAFE_ISUPPORTS + NS_DECL_NSIOBSERVER + + /// Initializes the singleton instance. Should be called from the main thread. + static void Initialize(); + + /// Returns the singleton instance. + static DecodePool* Singleton(); + + /// @return the number of processor cores we have available. This is not the + /// same as the number of decoding threads we're actually using. + static uint32_t NumberOfCores(); + + /// True if the DecodePool is being shutdown. This may only be called by + /// threads from the pool to check if they should keep working or not. + bool IsShuttingDown() const; + + /// Ask the DecodePool to run @aTask asynchronously and return immediately. + void AsyncRun(IDecodingTask* aTask); + + /** + * Run @aTask synchronously if the task would prefer it. It's up to the task + * itself to make this decision; @see IDecodingTask::ShouldPreferSyncRun(). If + * @aTask doesn't prefer it, just run @aTask asynchronously and return + * immediately. + * @return true if the task was run sync, false otherwise. + */ + bool SyncRunIfPreferred(IDecodingTask* aTask, const nsCString& aURI); + + /** + * Run @aTask synchronously. This does not guarantee that @aTask will complete + * synchronously. If, for example, @aTask doesn't yet have the data it needs + * to run synchronously, it may recover by scheduling an async task to finish + * up the work when the remaining data is available. + */ + void SyncRunIfPossible(IDecodingTask* aTask, const nsCString& aURI); + + /** + * Returns an event target interface to the DecodePool's I/O thread. Callers + * who want to deliver data to workers on the DecodePool can use this event + * target. + * + * @return An nsISerialEventTarget interface to the thread pool's I/O thread. + */ + already_AddRefed<nsISerialEventTarget> GetIOEventTarget(); + + private: + friend class DecodePoolWorker; + + DecodePool(); + virtual ~DecodePool(); + + static StaticRefPtr<DecodePool> sSingleton; + static uint32_t sNumCores; + bool mShuttingDown = false; + + // mMutex protects mIOThread. + Mutex mMutex; + nsCOMPtr<nsIThread> mIOThread MOZ_GUARDED_BY(mMutex); +}; + +} // namespace image +} // namespace mozilla + +#endif // mozilla_image_DecodePool_h |