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authorDavid S. Miller <davem@davemloft.net>2014-08-26 00:51:53 +0200
committerDavid S. Miller <davem@davemloft.net>2014-08-26 01:29:42 +0200
commit0b725a2ca61bedc33a2a63d0451d528b268cf975 (patch)
treeefe818013ee258eeff23f83ca0c8d01b5117a316 /drivers/spi
parentMerge branch 'is_kdump_kernel' (diff)
downloadlinux-0b725a2ca61bedc33a2a63d0451d528b268cf975.tar.xz
linux-0b725a2ca61bedc33a2a63d0451d528b268cf975.zip
net: Remove ndo_xmit_flush netdev operation, use signalling instead.
As reported by Jesper Dangaard Brouer, for high packet rates the overhead of having another indirect call in the TX path is non-trivial. There is the indirect call itself, and then there is all of the reloading of the state to refetch the tail pointer value and then write the device register. Move to a more passive scheme, which requires very light modifications to the device drivers. The signal is a new skb->xmit_more value, if it is non-zero it means that more SKBs are pending to be transmitted on the same queue as the current SKB. And therefore, the driver may elide the tail pointer update. Right now skb->xmit_more is always zero. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/spi')
0 files changed, 0 insertions, 0 deletions