[ovs-dev] [PATCH] datapath: fix sparse warning in function tbl_mask_array_delete_mask()

[Pravin Shelar]

On Mon, Jun 23, 2014 at 11:10 PM, Andy Zhou <azhou at nicira.com> wrote:
> Sparse gives "incompatible types in comparison expression (different
> address spaces)" warning messages. Fix this by add rcu_dereference()
> wrappers.
>
> Reported-by: Ben Pfaff <blp at nicira.com>
> Signed-off-by: Andy Zhou <azhou at nicira.com>
> ---
>  datapath/flow_table.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/datapath/flow_table.c b/datapath/flow_table.c
> index 41f7cb8..11261ec 100644
> --- a/datapath/flow_table.c
> +++ b/datapath/flow_table.c
> @@ -286,10 +286,10 @@ static void tbl_mask_array_delete_mask(struct mask_array *ma,
>          * </Note>
>          */
>         for (i = 0; i < ma->count; i++)
> -               if (mask == ma->masks[i]) {
> +               if (mask == rcu_dereference(ma->masks[i])) {
>                         struct sw_flow_mask *last;
>
> -                       last = ma->masks[ma->count - 1];
> +                       last = rcu_dereference(ma->masks[ma->count - 1]);
>                         rcu_assign_pointer(ma->masks[i], last);
>                         ma->count--;
>                         break;
> @@ -297,7 +297,7 @@ static void tbl_mask_array_delete_mask(struct mask_array *ma,
>
>         /* Remove the deleted mask pointers from the invalid section. */
>         for (i = ma->count; i < ma->max; i++)
> -               if (mask == ma->masks[i])
> +               if (mask == rcu_dereference(ma->masks[i]))
>                         RCU_INIT_POINTER(ma->masks[i], NULL);
>  }
>
tbl_mask_array_delete_mask() functions is always called under ovs
mutex, so deref needs to be done using ovsl_dereference()

Otherwise looks good.
Acked-by: Pravin B Shelar <pshelar at nicira.com>

> --
> 1.9.1
>
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