[PATCH 0/2] net: fs_enet: Remove non NAPI RX and add NAPI for TX

Christophe Leroy christophe.leroy at c-s.fr
Wed Oct 8 00:04:53 EST 2014

When using a MPC8xx as a router, 'perf' shows a significant time spent in 
fs_enet_interrupt() and fs_enet_start_xmit().
'perf annotate' shows that the time spent in fs_enet_start_xmit is indeed spent
between spin_unlock_irqrestore() and the following instruction, hence in
interrupt handling. This is due to the TX complete interrupt that fires after
each transmitted packet.
This patchset first remove all non NAPI handling as NAPI has become the only
mode for RX, then adds NAPI for handling TX complete.
This improves NAT TCP throughput by 21% on MPC885 with FEC.

Tested on MPC885 with FEC.

[PATCH 1/2] net: fs_enet: Remove non NAPI RX
[PATCH 2/2] net: fs_enet: Add NAPI TX

Signed-off-by: Christophe Leroy <christophe.leroy at c-s.fr>

 .../net/ethernet/freescale/fs_enet/fs_enet-main.c  | 211 ++++++---------------
 .../net/ethernet/freescale/fs_enet/fs_enet.h       |   9 +-
 .../net/ethernet/freescale/fs_enet/mac-fcc.c       |  29 +++
 .../net/ethernet/freescale/fs_enet/mac-fec.c       |  29 +++
 .../net/ethernet/freescale/fs_enet/mac-scc.c       |  29 +++
 linux/include/linux/fs_enet_pd.h                   |   1 -
 6 files changed, 147 insertions(+), 161 deletions(-)

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