Commit 90cacb2e authored Apr 10, 2017 by Ursula Braun Committed by David S. Miller Apr 11, 2017

net/smc: guarantee reset of write_blocked for heavy workload

If peer indicates write_blocked, the cursor state of the received data
should be send to the peer immediately (in smc_tx_consumer_update()).
Afterwards the write_blocked indicator is cleared.

If there is no free slot for another write request, sending is postponed
to worker smc_tx_work, and the write_blocked indicator is not cleared.
Therefore another clearing check is needed in smc_tx_work().

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 5da7e4d3

net/smc/smc_tx.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -431,9 +431,13 @@ static void smc_tx_work(struct work_struct *work)
		struct smc_connection,
		tx_work);
		struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
		int rc;

		lock_sock(&smc->sk);
		smc_tx_sndbuf_nonempty(conn);
		rc = smc_tx_sndbuf_nonempty(conn);
		if (!rc && conn->local_rx_ctrl.prod_flags.write_blocked &&
		!atomic_read(&conn->bytes_to_rcv))
		conn->local_rx_ctrl.prod_flags.write_blocked = 0;
		release_sock(&smc->sk);
		}

Admin message