diff options
| author | Chuck Lever <cel@netapp.com> | 2005-08-25 16:25:54 -0700 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2005-09-23 12:38:48 -0400 |
| commit | 555ee3af161b037865793bd4bebc06b58daafde6 (patch) | |
| tree | 4c72474dabffab62234db158e5b6c86ace4f9d09 /net/sunrpc/xprt.c | |
| parent | ed63c003701a314c4893c11eceb9d68f8f46c662 (diff) | |
| download | linux-555ee3af161b037865793bd4bebc06b58daafde6.tar.bz2 | |
[PATCH] RPC: clean up after nocong was removed
Clean-up: Move some macros that are specific to the Van Jacobson
implementation into xprt.c. Get rid of the cong_wait field in
rpc_xprt, which is no longer used. Get rid of xprt_clear_backlog.
Test-plan:
Compile with CONFIG_NFS enabled.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'net/sunrpc/xprt.c')
| -rw-r--r-- | net/sunrpc/xprt.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index e8d11bd6158e..0458319a1bdd 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -62,7 +62,23 @@ static inline void do_xprt_reserve(struct rpc_task *); static void xprt_connect_status(struct rpc_task *task); static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); -static int xprt_clear_backlog(struct rpc_xprt *xprt); +/* + * The transport code maintains an estimate on the maximum number of out- + * standing RPC requests, using a smoothed version of the congestion + * avoidance implemented in 44BSD. This is basically the Van Jacobson + * congestion algorithm: If a retransmit occurs, the congestion window is + * halved; otherwise, it is incremented by 1/cwnd when + * + * - a reply is received and + * - a full number of requests are outstanding and + * - the congestion window hasn't been updated recently. + */ +#define RPC_CWNDSHIFT (8U) +#define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) +#define RPC_INITCWND RPC_CWNDSCALE +#define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) + +#define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) /** * xprt_reserve_xprt - serialize write access to transports @@ -850,7 +866,7 @@ void xprt_release(struct rpc_task *task) spin_lock(&xprt->reserve_lock); list_add(&req->rq_list, &xprt->free); - xprt_clear_backlog(xprt); + rpc_wake_up_next(&xprt->backlog); spin_unlock(&xprt->reserve_lock); } @@ -902,7 +918,6 @@ static struct rpc_xprt *xprt_setup(int proto, struct sockaddr_in *ap, struct rpc spin_lock_init(&xprt->transport_lock); spin_lock_init(&xprt->reserve_lock); - init_waitqueue_head(&xprt->cong_wait); INIT_LIST_HEAD(&xprt->free); INIT_LIST_HEAD(&xprt->recv); @@ -911,6 +926,7 @@ static struct rpc_xprt *xprt_setup(int proto, struct sockaddr_in *ap, struct rpc xprt->timer.function = xprt_init_autodisconnect; xprt->timer.data = (unsigned long) xprt; xprt->last_used = jiffies; + xprt->cwnd = RPC_INITCWND; rpc_init_wait_queue(&xprt->pending, "xprt_pending"); rpc_init_wait_queue(&xprt->sending, "xprt_sending"); @@ -955,16 +971,9 @@ static void xprt_shutdown(struct rpc_xprt *xprt) rpc_wake_up(&xprt->resend); xprt_wake_pending_tasks(xprt, -EIO); rpc_wake_up(&xprt->backlog); - wake_up(&xprt->cong_wait); del_timer_sync(&xprt->timer); } -static int xprt_clear_backlog(struct rpc_xprt *xprt) { - rpc_wake_up_next(&xprt->backlog); - wake_up(&xprt->cong_wait); - return 1; -} - /** * xprt_destroy - destroy an RPC transport, killing off all requests. * @xprt: transport to destroy |