Function freeClientAsync

src/networking.cpp:1759–1772

Schedule a client to free it at a safe time in the serverCron() function. * This function is useful when we need to terminate a client but we are in * a context where calling freeClient() is not possible, because the client * should be valid for the continuation of the flow of the program. */

 * a context where calling freeClient() is not possible, because the client
 * should be valid for the continuation of the flow of the program. */
void freeClientAsync(client *c) {
    /* We need to handle concurrent access to the g_pserver->clients_to_close list
     * only in the freeClientAsync() function, since it's the only function that
     * may access the list while Redis uses I/O threads. All the other accesses
     * are in the context of the main thread while the other threads are
     * idle. */
    if (c->flags & CLIENT_CLOSE_ASAP || c->flags & CLIENT_LUA) return;  // check without the lock first
    std::lock_guard<decltype(c->lock)> clientlock(c->lock);
    if (c->flags & CLIENT_CLOSE_ASAP || c->flags & CLIENT_LUA) return;  // race condition after we acquire the lock
    c->flags |= CLIENT_CLOSE_ASAP;
    c->repl_down_since = g_pserver->unixtime;
    std::unique_lock<fastlock> ul(g_lockasyncfree);
    listAddNodeTail(g_pserver->clients_to_close,c);
}

int freeClientsInAsyncFreeQueue(int iel) {
    serverAssert(GlobalLocksAcquired());