From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Duyck , Jeff Pieper , Jeff Kirsher , Vinson Lee Subject: [ 8/8] igb: Remove artificial restriction on RQDPC stat reading Date: Fri, 15 Feb 2013 14:56:15 -0800 Message-Id: <20130215225431.827647377@linuxfoundation.org> In-Reply-To: <20130215225430.841634159@linuxfoundation.org> References: <20130215225430.841634159@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexander Duyck commit ae1c07a6b7ced6c0c94c99e3b53f4e7856fa8bff upstream. For some reason the reading of the RQDPC register was being artificially limited to 4K. Instead of limiting the value we should read the value and add the full amount. Otherwise this can lead to a misleading number of dropped packets when the actual value is in fact much higher. Signed-off-by: Alexander Duyck Tested-by: Jeff Pieper Signed-off-by: Jeff Kirsher Cc: Vinson Lee Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/intel/igb/igb_main.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -4649,11 +4649,13 @@ void igb_update_stats(struct igb_adapter bytes = 0; packets = 0; for (i = 0; i < adapter->num_rx_queues; i++) { - u32 rqdpc_tmp = rd32(E1000_RQDPC(i)) & 0x0FFF; + u32 rqdpc = rd32(E1000_RQDPC(i)); struct igb_ring *ring = adapter->rx_ring[i]; - ring->rx_stats.drops += rqdpc_tmp; - net_stats->rx_fifo_errors += rqdpc_tmp; + if (rqdpc) { + ring->rx_stats.drops += rqdpc; + net_stats->rx_fifo_errors += rqdpc; + } do { start = u64_stats_fetch_begin_bh(&ring->rx_syncp);