diff options
Diffstat (limited to 'debian/patches/libdde_dma_head.patch')
| -rw-r--r-- | debian/patches/libdde_dma_head.patch | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/debian/patches/libdde_dma_head.patch b/debian/patches/libdde_dma_head.patch new file mode 100644 index 00000000..1a1c75fd --- /dev/null +++ b/debian/patches/libdde_dma_head.patch @@ -0,0 +1,93 @@ +commit 042a53a9e437feaf2230dd2cadcecfae9c7bfe05 +Author: Eric Dumazet <eric.dumazet@gmail.com> +Date: Fri Jun 5 04:04:16 2009 +0000 + + net: skb_shared_info optimization + + skb_dma_unmap() is quite expensive for small packets, + because we use two different cache lines from skb_shared_info. + + One to access nr_frags, one to access dma_maps[0] + + Instead of dma_maps being an array of MAX_SKB_FRAGS + 1 elements, + let dma_head alone in a new dma_head field, close to nr_frags, + to reduce cache lines misses. + + Tested on my dev machine (bnx2 & tg3 adapters), nice speedup ! + + Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> + Signed-off-by: David S. Miller <davem@davemloft.net> + +Index: hurd-debian/libdde_linux26/contrib/include/linux/skbuff.h +=================================================================== +--- hurd-debian.orig/libdde_linux26/contrib/include/linux/skbuff.h 2012-04-16 00:26:40.000000000 +0000 ++++ hurd-debian/libdde_linux26/contrib/include/linux/skbuff.h 2012-04-16 00:34:56.000000000 +0000 +@@ -142,6 +142,9 @@ + atomic_t dataref; + unsigned short nr_frags; + unsigned short gso_size; ++#ifdef CONFIG_HAS_DMA ++ dma_addr_t dma_head; ++#endif + /* Warning: this field is not always filled in (UFO)! */ + unsigned short gso_segs; + unsigned short gso_type; +@@ -152,7 +155,7 @@ + struct sk_buff *frag_list; + skb_frag_t frags[MAX_SKB_FRAGS]; + #ifdef CONFIG_HAS_DMA +- dma_addr_t dma_maps[MAX_SKB_FRAGS + 1]; ++ dma_addr_t dma_maps[MAX_SKB_FRAGS]; + #endif + }; + +Index: hurd-debian/libdde_linux26/contrib/net/core/skb_dma_map.c +=================================================================== +--- hurd-debian.orig/libdde_linux26/contrib/net/core/skb_dma_map.c 2012-04-16 00:26:40.000000000 +0000 ++++ hurd-debian/libdde_linux26/contrib/net/core/skb_dma_map.c 2012-04-16 00:34:56.000000000 +0000 +@@ -20,7 +20,7 @@ + if (dma_mapping_error(dev, map)) + goto out_err; + +- sp->dma_maps[0] = map; ++ sp->dma_head = map; + for (i = 0; i < sp->nr_frags; i++) { + skb_frag_t *fp = &sp->frags[i]; + +@@ -28,7 +28,7 @@ + fp->size, dir); + if (dma_mapping_error(dev, map)) + goto unwind; +- sp->dma_maps[i + 1] = map; ++ sp->dma_maps[i] = map; + } + sp->num_dma_maps = i + 1; + +@@ -38,10 +38,10 @@ + while (--i >= 0) { + skb_frag_t *fp = &sp->frags[i]; + +- dma_unmap_page(dev, sp->dma_maps[i + 1], ++ dma_unmap_page(dev, sp->dma_maps[i], + fp->size, dir); + } +- dma_unmap_single(dev, sp->dma_maps[0], ++ dma_unmap_single(dev, sp->dma_head, + skb_headlen(skb), dir); + out_err: + return -ENOMEM; +@@ -54,12 +54,12 @@ + struct skb_shared_info *sp = skb_shinfo(skb); + int i; + +- dma_unmap_single(dev, sp->dma_maps[0], ++ dma_unmap_single(dev, sp->dma_head, + skb_headlen(skb), dir); + for (i = 0; i < sp->nr_frags; i++) { + skb_frag_t *fp = &sp->frags[i]; + +- dma_unmap_page(dev, sp->dma_maps[i + 1], ++ dma_unmap_page(dev, sp->dma_maps[i], + fp->size, dir); + } + } |