Re: [PATCH 2/2] af_packet: replace struct pgv with char **

[Eric Dumazet <eric.dumazet@gmail.com>]

Le mardi 30 novembre 2010 à 21:57 +0800, Changli Gao a écrit :
> As we can check if an address is vmalloc address with is_vmalloc_addr(),
> we can replace struct pgv with char **. Then we may get more pg_vecs.
> 
> Signed-off-by: Changli Gao <xiaosuo@gmail.com>
> ---
>  net/packet/af_packet.c |   50 ++++++++++++++++---------------------------------
>  1 file changed, 17 insertions(+), 33 deletions(-)
> diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
> index 0171b20..a26f981 100644
> --- a/net/packet/af_packet.c
> +++ b/net/packet/af_packet.c
> @@ -164,14 +164,8 @@ struct packet_mreq_max {
>  static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
>  		int closing, int tx_ring);
>  
> -#define PGV_FROM_VMALLOC 1
> -struct pgv {
> -	char *buffer;
> -	unsigned char flags;
> -};
> -

This patch is premature.

Also, keep the struct pgv, even if it has a single field, since having
types is good to read the sources.

We could have 'void *' or 'char *' everywhere, it is not nice...


-       pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
+       pg_vec = kcalloc(block_nr, sizeof(char *), GFP_KERNEL);

I prefer to have :

       pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);