From 5f06eba4dce361bfc077868d044768476b41d698 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 28 Nov 2007 14:50:16 -0800 Subject: [PATCH] sky2: rx allocation threshold change When using larger MTU's sky2 driver changes from allocating one data area, to using multiple pages. The threshold for this was based on a heuristic where the cost of a single allocation is bigger than one page. Since the allocator has changed, this heuristic is now incorrect; instead just make the threshold be when the total size of the allocation is greater than one page. Signed-off-by: Stephen Hemminger Signed-off-by: Jeff Garzik --- drivers/net/sky2.c | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-) diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c index 30e567a2d5a..c177e87182f 100644 --- a/drivers/net/sky2.c +++ b/drivers/net/sky2.c @@ -1234,7 +1234,7 @@ static int sky2_rx_start(struct sky2_port *sky2) struct sky2_hw *hw = sky2->hw; struct rx_ring_info *re; unsigned rxq = rxqaddr[sky2->port]; - unsigned i, size, space, thresh; + unsigned i, size, thresh; sky2->rx_put = sky2->rx_next = 0; sky2_qset(hw, rxq); @@ -1261,28 +1261,18 @@ static int sky2_rx_start(struct sky2_port *sky2) /* Stopping point for hardware truncation */ thresh = (size - 8) / sizeof(u32); - /* Account for overhead of skb - to avoid order > 0 allocation */ - space = SKB_DATA_ALIGN(size) + NET_SKB_PAD - + sizeof(struct skb_shared_info); - - sky2->rx_nfrags = space >> PAGE_SHIFT; + sky2->rx_nfrags = size >> PAGE_SHIFT; BUG_ON(sky2->rx_nfrags > ARRAY_SIZE(re->frag_addr)); - if (sky2->rx_nfrags != 0) { - /* Compute residue after pages */ - space = sky2->rx_nfrags << PAGE_SHIFT; + /* Compute residue after pages */ + size -= sky2->rx_nfrags << PAGE_SHIFT; - if (space < size) - size -= space; - else - size = 0; + /* Optimize to handle small packets and headers */ + if (size < copybreak) + size = copybreak; + if (size < ETH_HLEN) + size = ETH_HLEN; - /* Optimize to handle small packets and headers */ - if (size < copybreak) - size = copybreak; - if (size < ETH_HLEN) - size = ETH_HLEN; - } sky2->rx_data_size = size; /* Fill Rx ring */ -- 2.11.4.GIT