bool ConcurrentTableSharedStore::handlePromoteObj(CStrRef key, SharedVariant* svar, CVarRef value) { SharedVariant *converted = svar->convertObj(value); if (converted) { Map::accessor acc; if (!m_vars.find(acc, key.data())) { // There is a chance another thread deletes the key when this thread is // converting the object. In that case, we just bail converted->decRef(); return false; } // A write lock was acquired during find StoreValue *sval = &acc->second; SharedVariant *sv = sval->var; // sv may not be same as svar here because some other thread may have // updated it already, check before updating if (sv == svar && !sv->isUnserializedObj()) { int64 ttl = sval->expiry ? sval->expiry - time(NULL) : 0; stats_on_update(key.get(), sval, converted, ttl); sval->var = converted; sv->decRef(); return true; } converted->decRef(); } return false; }
bool ConcurrentTableSharedStore::get(CStrRef key, Variant &value) { bool stats = RuntimeOption::EnableStats && RuntimeOption::EnableAPCStats; bool statsFetch = RuntimeOption::EnableAPCSizeStats && RuntimeOption::EnableAPCFetchStats; const StoreValue *val; SharedVariant *svar = NULL; ReadLock l(m_lock); bool expired = false; { Map::const_accessor acc; if (!m_vars.find(acc, key.data())) { if (stats) ServerStats::Log("apc.miss", 1); return false; } else { val = &acc->second; if (val->expired()) { // Because it only has a read lock on the data, deletion from // expiration has to happen after the lock is released expired = true; } else { svar = val->var; if (RuntimeOption::ApcAllowObj) { // Hold ref here svar->incRef(); } value = svar->toLocal(); if (statsFetch) { SharedStoreStats::onGet(key.get(), svar); } } } } if (expired) { if (stats) { ServerStats::Log("apc.miss", 1); } eraseImpl(key, true); return false; } if (stats) { ServerStats::Log("apc.hit", 1); } if (RuntimeOption::ApcAllowObj) { bool statsDetail = RuntimeOption::EnableAPCSizeStats && RuntimeOption::EnableAPCSizeGroup; SharedVariant *converted = svar->convertObj(value); if (converted) { Map::accessor acc; m_vars.find(acc, key.data()); // start a write lock StoreValue *sval = &acc->second; SharedVariant *sv = sval->var; // sv may not be same as svar here because some other thread may have // updated it already, check before updating if (!sv->isUnserializedObj()) { if (statsDetail) { SharedStoreStats::onDelete(key.get(), sv, true); } sval->var = converted; sv->decRef(); if (RuntimeOption::EnableAPCSizeStats) { int32 newSize = converted->getSpaceUsage(); SharedStoreStats::updateDirect(sval->size, newSize); sval->size = newSize; } if (statsDetail) { int64 ttl = sval->expiry ? sval->expiry - time(NULL) : 0; SharedStoreStats::onStore(key.get(), converted, ttl, false); } } else { converted->decRef(); } } // release the extra ref svar->decRef(); } return true; }