[ovs-dev] [PATCH 2/2] datapath: Remove RT kernel support.

[Jesse Gross]

On Thu, Oct 6, 2011 at 3:13 PM, Pravin B Shelar <pshelar at nicira.com> wrote:
> Following patch removes RT kernel support. This allows us to cleanup
> the loop detection.
> Along with this BH is now disabled while running execute_actions()
> for packet from user-space.
> As a result we can simplify the stats code as entire send and receive
> path runs in BH context on all supported platforms.
>
> Signed-off-by: Pravin B Shelar <pshelar at nicira.com>
> Bug #7621
> ---
>  datapath/Modules.mk                               |    2 -
>  datapath/actions.c                                |   27 +++++++-
>  datapath/datapath.c                               |   20 ++----
>  datapath/flow.c                                   |    4 +-
>  datapath/linux/compat/include/linux/bottom_half.h |   19 ------
>  datapath/loop_counter.c                           |   72 ---------------------
>  datapath/loop_counter.h                           |   28 --------
>  datapath/tunnel.c                                 |    8 +-
>  datapath/vport-internal_dev.c                     |    5 +-
>  datapath/vport.c                                  |   10 +--
>  10 files changed, 41 insertions(+), 154 deletions(-)
>  delete mode 100644 datapath/linux/compat/include/linux/bottom_half.h
>  delete mode 100644 datapath/loop_counter.c
>  delete mode 100644 datapath/loop_counter.h

You need to remove bottom_half.h from linux/Modules.mk as well or make
dist fails.

> diff --git a/datapath/actions.c b/datapath/actions.c
> index 36437a4..a868164 100644
> --- a/datapath/actions.c
> +++ b/datapath/actions.c
> @@ -388,7 +409,7 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb)
>        int error;
>
>        /* Check whether we've looped too much. */
> -       loop = loop_get_counter();
> +       loop = &get_cpu_var(loop_counters);

Since bottom halves are disabled here, the CPU can't change out from
under us and we can use __get_cpu_var and drop put_cpu_var.

Otherwise looks good:
Acked-by: Jesse Gross <jesse at nicira.com>