From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter P Waskiewicz Jr Subject: [net-next 1/9] ixgbe: Remove code that was initializing Rx page offset Date: Thu, 16 Aug 2012 15:48:30 -0700 Message-ID: <1345157318-23731-2-git-send-email-peter.p.waskiewicz.jr@intel.com> References: <1345157318-23731-1-git-send-email-peter.p.waskiewicz.jr@intel.com> Cc: Alexander Duyck , netdev@vger.kernel.org, gospo@redhat.com, sassmann@redhat.com, Peter P Waskiewicz Jr To: davem@davemloft.net Return-path: Received: from mga09.intel.com ([134.134.136.24]:12017 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755378Ab2HPWst (ORCPT ); Thu, 16 Aug 2012 18:48:49 -0400 In-Reply-To: <1345157318-23731-1-git-send-email-peter.p.waskiewicz.jr@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Alexander Duyck This change reverts an earlier patch that introduced ixgbe_init_rx_page_offset. The idea behind the function was to provide some variation in the starting offset for the page in order to reduce hot-spots in the cache. However it doesn't appear to provide any significant benefit in the testing I have done. It has however been a source of several bugs, and it blocks us from being able to use 2K fragments on larger page sizes. So the decision I made was to remove it. Signed-off-by: Alexander Duyck Tested-by: Phil Schmitt Signed-off-by: Peter P Waskiewicz Jr --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 27 +-------------------------- 1 file changed, 1 insertion(+), 26 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 4326f74..f7351c6 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -1167,7 +1167,7 @@ static bool ixgbe_alloc_mapped_page(struct ixgbe_ring *rx_ring, } bi->dma = dma; - bi->page_offset ^= ixgbe_rx_bufsz(rx_ring); + bi->page_offset = 0; return true; } @@ -4130,27 +4130,6 @@ void ixgbe_reset(struct ixgbe_adapter *adapter) } /** - * ixgbe_init_rx_page_offset - initialize page offset values for Rx buffers - * @rx_ring: ring to setup - * - * On many IA platforms the L1 cache has a critical stride of 4K, this - * results in each receive buffer starting in the same cache set. To help - * reduce the pressure on this cache set we can interleave the offsets so - * that only every other buffer will be in the same cache set. - **/ -static void ixgbe_init_rx_page_offset(struct ixgbe_ring *rx_ring) -{ - struct ixgbe_rx_buffer *rx_buffer = rx_ring->rx_buffer_info; - u16 i; - - for (i = 0; i < rx_ring->count; i += 2) { - rx_buffer[0].page_offset = 0; - rx_buffer[1].page_offset = ixgbe_rx_bufsz(rx_ring); - rx_buffer = &rx_buffer[2]; - } -} - -/** * ixgbe_clean_rx_ring - Free Rx Buffers per Queue * @rx_ring: ring to free buffers from **/ @@ -4195,8 +4174,6 @@ static void ixgbe_clean_rx_ring(struct ixgbe_ring *rx_ring) size = sizeof(struct ixgbe_rx_buffer) * rx_ring->count; memset(rx_ring->rx_buffer_info, 0, size); - ixgbe_init_rx_page_offset(rx_ring); - /* Zero out the descriptor ring */ memset(rx_ring->desc, 0, rx_ring->size); @@ -4646,8 +4623,6 @@ int ixgbe_setup_rx_resources(struct ixgbe_ring *rx_ring) rx_ring->next_to_clean = 0; rx_ring->next_to_use = 0; - ixgbe_init_rx_page_offset(rx_ring); - return 0; err: vfree(rx_ring->rx_buffer_info); -- 1.7.11.2