From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: [net-next 22/25] fm10k: reset head instead of calling update_max_size Date: Tue, 14 Apr 2015 16:51:08 -0700 Message-ID: <1429055471-401-23-git-send-email-jeffrey.t.kirsher@intel.com> References: <1429055471-401-1-git-send-email-jeffrey.t.kirsher@intel.com> Cc: Jeff Kirsher , netdev@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, jogreene@redhat.com, Jacob Keller To: davem@davemloft.net Return-path: Received: from mga11.intel.com ([192.55.52.93]:51346 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755079AbbDNXv3 (ORCPT ); Tue, 14 Apr 2015 19:51:29 -0400 In-Reply-To: <1429055471-401-1-git-send-email-jeffrey.t.kirsher@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: When we forcefully shutdown the mailbox, we then go about resetting max size to 0, and clearing all messages in the FIFO. Instead, we should just reset the head pointer so that the FIFO becomes empty, rather than changing the max size to 0. This helps prevent increment in tx_dropped counter during mailbox negotiation, which is confusing to viewers of Linux ethtool statistics output. Signed-off-by: Jeff Kirsher Signed-off-by: Jacob Keller Acked-by: Matthew Vick Tested-by: Krishneil Singh --- drivers/net/ethernet/intel/fm10k/fm10k_mbx.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_mbx.c b/drivers/net/ethernet/intel/fm10k/fm10k_mbx.c index e9ecfb4..27f8279 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_mbx.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_mbx.c @@ -126,6 +126,18 @@ static u16 fm10k_fifo_head_drop(struct fm10k_mbx_fifo *fifo) } /** + * fm10k_fifo_drop_all - Drop all messages in FIFO + * @fifo: pointer to FIFO + * + * This function resets the head pointer to drop all messages in the FIFO, + * and ensure the FIFO is empty. + **/ +static void fm10k_fifo_drop_all(struct fm10k_mbx_fifo *fifo) +{ + fifo->head = fifo->tail; +} + +/** * fm10k_mbx_index_len - Convert a head/tail index into a length value * @mbx: pointer to mailbox * @head: head index @@ -1370,9 +1382,11 @@ static void fm10k_mbx_disconnect(struct fm10k_hw *hw, timeout -= FM10K_MBX_POLL_DELAY; } while ((timeout > 0) && (mbx->state != FM10K_STATE_CLOSED)); - /* in case we didn't close just force the mailbox into shutdown */ + /* in case we didn't close, just force the mailbox into shutdown and + * drop all left over messages in the FIFO. + */ fm10k_mbx_connect_reset(mbx); - fm10k_mbx_update_max_size(mbx, 0); + fm10k_fifo_drop_all(&mbx->tx); fm10k_write_reg(hw, mbx->mbmem_reg, 0); } -- 1.9.3