am 715bcd6d: am 1bf15e79: am 97ece7a9: Merge "EGL: add deferred saving of the cache" into ics-mr1

static const char* cacheFileMagic = "EGL$";

static const size_t cacheFileHeaderSize = 8;

// The time in seconds to wait before saving newly inserted cache entries.

static const unsigned int deferredSaveDelay = 4;

// ----------------------------------------------------------------------------

namespace android {

// ----------------------------------------------------------------------------

    if (mInitialized) {

        sp<BlobCache> bc = getBlobCacheLocked();

        bc->set(key, keySize, value, valueSize);

        if (!mSavePending) {

            class DeferredSaveThread : public Thread {

            public:

                DeferredSaveThread() : Thread(false) {}

                virtual bool threadLoop() {

                    sleep(deferredSaveDelay);

                    egl_cache_t* c = egl_cache_t::get();

                    Mutex::Autolock lock(c->mMutex);

                    if (c->mInitialized) {

                        c->saveBlobCacheLocked();

                    }

                    c->mSavePending = false;

                    return false;

                }

            };

            // The thread will hold a strong ref to itself until it has finished

            // running, so there's no need to keep a ref around.

            sp<Thread> deferredSaveThread(new DeferredSaveThread());

            mSavePending = true;

            deferredSaveThread->run();

        }

    }

}

    // from disk.

    String8 mFilename;

    // mSavePending indicates whether or not a deferred save operation is

    // pending.  Each time a key/value pair is inserted into the cache via

    // setBlob, a deferred save is initiated if one is not already pending.

    // This will wait some amount of time and then trigger a save of the cache

    // contents to disk.

    bool mSavePending;

    // mMutex is the mutex used to prevent concurrent access to the member

    // variables. It must be locked whenever the member variables are accessed.

    mutable Mutex mMutex;