[sheepdog] [PATCH 3/9] gateway: remove shortcut for local node in gateway_forward_request

[MORITA Kazutaka]

At Thu, 19 Sep 2013 18:42:47 +0800,
Liu Yuan wrote:
> 
> Signed-off-by: Liu Yuan <namei.unix at gmail.com>
> ---
>  sheep/gateway.c |   20 +-------------------
>  1 file changed, 1 insertion(+), 19 deletions(-)
> 
> diff --git a/sheep/gateway.c b/sheep/gateway.c
> index 016d69a..a61d730 100644
> --- a/sheep/gateway.c
> +++ b/sheep/gateway.c
> @@ -236,11 +236,10 @@ write_info_advance(struct write_info *wi, const struct node_id *nid,
>  
>  static int gateway_forward_request(struct request *req)
>  {
> -	int i, err_ret = SD_RES_SUCCESS, ret, local = -1;
> +	int i, err_ret = SD_RES_SUCCESS, ret;
>  	unsigned wlen;
>  	uint64_t oid = req->rq.obj.oid;
>  	struct write_info wi;
> -	const struct sd_op_template *op;
>  	struct sd_req hdr;
>  	const struct sd_node *target_nodes[SD_MAX_NODES];
>  	int nr_copies = get_req_copy_number(req);
> @@ -248,7 +247,6 @@ static int gateway_forward_request(struct request *req)
>  	sd_debug("%"PRIx64, oid);
>  
>  	gateway_init_fwd_hdr(&hdr, &req->rq);
> -	op = get_sd_op(hdr.opcode);
>  
>  	wlen = hdr.data_length;
>  	oid_to_nodes(oid, &req->vinfo->vroot, nr_copies, target_nodes);
> @@ -258,11 +256,6 @@ static int gateway_forward_request(struct request *req)
>  		struct sockfd *sfd;
>  		const struct node_id *nid;
>  
> -		if (node_is_local(target_nodes[i])) {
> -			local = i;
> -			continue;
> -		}
> -
>  		nid = &target_nodes[i]->nid;
>  		sfd = sockfd_cache_get(nid);
>  		if (!sfd) {
> @@ -282,17 +275,6 @@ static int gateway_forward_request(struct request *req)
>  		write_info_advance(&wi, nid, sfd);
>  	}
>  
> -	if (local != -1 && err_ret == SD_RES_SUCCESS) {
> -		assert(op);
> -		ret = sheep_do_op_work(op, req);
> -
> -		if (ret != SD_RES_SUCCESS) {
> -			sd_err("fail to write local %"PRIx64", %s", oid,
> -			       sd_strerror(ret));
> -			err_ret = ret;
> -		}
> -	}
> -
>  	sd_debug("nr_sent %d, err %x", wi.nr_sent, err_ret);
>  	if (wi.nr_sent > 0) {
>  		ret = wait_forward_request(&wi, req);

This introduces overhead when the target node is local.  Please
explain in the commit log why this change gives us more benefits than
the performance penalty.

Thanks,

Kazutaka