[net-next 1/9] ixgbe: Remove code that was initializing Rx page offset
flat view
From: Peter P Waskiewicz Jr <hidden>
Date: 2012-08-16 22:48:49
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Alexander Duyck <redacted> 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 <redacted> Tested-by: Phil Schmitt <redacted> Signed-off-by: Peter P Waskiewicz Jr <redacted> --- 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