lkml.org 
[lkml]   [2010]   [Mar]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[143/156] skbuff: remove unused dma_head & dma_maps fields
    2.6.33-stable review patch.  If anyone has any objections, please let us know.

    ------------------

    From: Alexander Duyck <alexander.h.duyck@intel.com>

    [ Upstream commit 03e6d819c2cb2cc8ce5642669a0a7c72336ee7a2 ]

    The dma map fields in the skb_shared_info structure no longer has any users
    and can be dropped since it is making the skb_shared_info unecessarily larger.

    Running slabtop show that we were using 4K slabs for the skb->head on x86_64 w/
    an allocation size of 1522. It turns out that the dma_head and dma_maps array
    made skb_shared large enough that we had crossed over the 2k boundary with
    standard frames and as such we were using 4k blocks of memory for all skbs.

    Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
    Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
    Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
    Signed-off-by: David S. Miller <davem@davemloft.net>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    include/linux/skbuff.h | 6 ------
    1 file changed, 6 deletions(-)

    --- a/include/linux/skbuff.h
    +++ b/include/linux/skbuff.h
    @@ -190,9 +190,6 @@ struct skb_shared_info {
    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;
    @@ -201,9 +198,6 @@ struct skb_shared_info {
    struct sk_buff *frag_list;
    struct skb_shared_hwtstamps hwtstamps;
    skb_frag_t frags[MAX_SKB_FRAGS];
    -#ifdef CONFIG_HAS_DMA
    - dma_addr_t dma_maps[MAX_SKB_FRAGS];
    -#endif
    /* Intermediate layers must ensure that destructor_arg
    * remains valid until skb destructor */
    void * destructor_arg;



    \
     
     \ /
      Last update: 2010-03-31 01:29    [W:4.123 / U:0.252 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site