| From 0d0f660d882c1c02748ced13966a2413aa5d6cc2 Mon Sep 17 00:00:00 2001 |
| From: Nicholas Bellinger <nab@linux-iscsi.org> |
| Date: Sun, 5 Oct 2014 02:13:03 -0700 |
| Subject: iser-target: Disable TX completion interrupt coalescing |
| |
| From: Nicholas Bellinger <nab@linux-iscsi.org> |
| |
| commit 0d0f660d882c1c02748ced13966a2413aa5d6cc2 upstream. |
| |
| This patch explicitly disables TX completion interrupt coalescing logic |
| in isert_put_response() and isert_put_datain() that was originally added |
| as an efficiency optimization in commit 95b60f07. |
| |
| It has been reported that this change can trigger ABORT_TASK timeouts |
| under certain small block workloads, where disabling coalescing was |
| required for stability. According to Sagi, this doesn't impact |
| overall performance, so go ahead and disable it for now. |
| |
| Reported-by: Moussa Ba <moussaba@micron.com> |
| Reported-by: Sagi Grimberg <sagig@dev.mellanox.co.il> |
| Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| |
| --- |
| drivers/infiniband/ulp/isert/ib_isert.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/infiniband/ulp/isert/ib_isert.c |
| +++ b/drivers/infiniband/ulp/isert/ib_isert.c |
| @@ -1953,7 +1953,7 @@ isert_put_response(struct iscsi_conn *co |
| isert_cmd->tx_desc.num_sge = 2; |
| } |
| |
| - isert_init_send_wr(isert_conn, isert_cmd, send_wr, true); |
| + isert_init_send_wr(isert_conn, isert_cmd, send_wr, false); |
| |
| pr_debug("Posting SCSI Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n"); |
| |
| @@ -2472,7 +2472,7 @@ isert_put_datain(struct iscsi_conn *conn |
| &isert_cmd->tx_desc.iscsi_header); |
| isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc); |
| isert_init_send_wr(isert_conn, isert_cmd, |
| - &isert_cmd->tx_desc.send_wr, true); |
| + &isert_cmd->tx_desc.send_wr, false); |
| |
| atomic_add(wr->send_wr_num + 1, &isert_conn->post_send_buf_count); |
| |
