From 5a02cbd10d37889d8214e82d57ccc70307edf805 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 20 Jul 2012 08:08:51 +0000 Subject: [PATCH] ixgbe: Roll RSC code into non-EOP code This change moves the RSC code into the non-EOP descriptor handling function. The main motivation behind this change is to help reduce the overhead in the non-RSC case. Previously the non-RSC path code would always be checking for append count even if RSC had been disabled. Now this code is completely skipped in a single conditional check instead of having to make two separate checks. Signed-off-by: Alexander Duyck Tested-by: Phil Schmitt Signed-off-by: Peter P Waskiewicz Jr --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 51 ++++++++++----------------- 1 file changed, 19 insertions(+), 32 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 9e72ae6..aa37b84 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -1320,29 +1320,6 @@ static unsigned int ixgbe_get_headlen(unsigned char *data, return max_len; } -static void ixgbe_get_rsc_cnt(struct ixgbe_ring *rx_ring, - union ixgbe_adv_rx_desc *rx_desc, - struct sk_buff *skb) -{ - __le32 rsc_enabled; - u32 rsc_cnt; - - if (!ring_is_rsc_enabled(rx_ring)) - return; - - rsc_enabled = rx_desc->wb.lower.lo_dword.data & - cpu_to_le32(IXGBE_RXDADV_RSCCNT_MASK); - - /* If this is an RSC frame rsc_cnt should be non-zero */ - if (!rsc_enabled) - return; - - rsc_cnt = le32_to_cpu(rsc_enabled); - rsc_cnt >>= IXGBE_RXDADV_RSCCNT_SHIFT; - - IXGBE_CB(skb)->append_cnt += rsc_cnt - 1; -} - static void ixgbe_set_rsc_gso_size(struct ixgbe_ring *ring, struct sk_buff *skb) { @@ -1440,16 +1417,28 @@ static bool ixgbe_is_non_eop(struct ixgbe_ring *rx_ring, prefetch(IXGBE_RX_DESC(rx_ring, ntc)); - if (likely(ixgbe_test_staterr(rx_desc, IXGBE_RXD_STAT_EOP))) - return false; + /* update RSC append count if present */ + if (ring_is_rsc_enabled(rx_ring)) { + __le32 rsc_enabled = rx_desc->wb.lower.lo_dword.data & + cpu_to_le32(IXGBE_RXDADV_RSCCNT_MASK); + + if (unlikely(rsc_enabled)) { + u32 rsc_cnt = le32_to_cpu(rsc_enabled); + + rsc_cnt >>= IXGBE_RXDADV_RSCCNT_SHIFT; + IXGBE_CB(skb)->append_cnt += rsc_cnt - 1; - /* append_cnt indicates packet is RSC, if so fetch nextp */ - if (IXGBE_CB(skb)->append_cnt) { - ntc = le32_to_cpu(rx_desc->wb.upper.status_error); - ntc &= IXGBE_RXDADV_NEXTP_MASK; - ntc >>= IXGBE_RXDADV_NEXTP_SHIFT; + /* update ntc based on RSC value */ + ntc = le32_to_cpu(rx_desc->wb.upper.status_error); + ntc &= IXGBE_RXDADV_NEXTP_MASK; + ntc >>= IXGBE_RXDADV_NEXTP_SHIFT; + } } + /* if we are the last buffer then there is nothing else to do */ + if (likely(ixgbe_test_staterr(rx_desc, IXGBE_RXD_STAT_EOP))) + return false; + /* place skb in next buffer to be received */ rx_ring->rx_buffer_info[ntc].skb = skb; rx_ring->rx_stats.non_eop_descs++; @@ -1829,8 +1818,6 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, if (!skb) break; - ixgbe_get_rsc_cnt(rx_ring, rx_desc, skb); - cleaned_count++; /* place incomplete frames back on ring for completion */ -- 2.7.4