static void
__xprt_lock_write_next(struct rpc_xprt *xprt)
{
struct rpc_task *task;
if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate))
return;
if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
goto out_unlock;
task = rpc_wake_up_next(&xprt->resend);
if (!task) {
task = rpc_wake_up_next(&xprt->sending);
if (!task)
goto out_unlock;
}
if (xprt->nocong || __xprt_get_cong(xprt, task)) {
struct rpc_rqst *req = task->tk_rqstp;
xprt->snd_task = task;
if (req) {
req->rq_bytes_sent = 0;
req->rq_ntrans++;
}
return;
}
out_unlock:
smp_mb__before_clear_bit();
clear_bit(XPRT_LOCKED, &xprt->sockstate);
smp_mb__after_clear_bit();
}
/*
* Van Jacobson congestion avoidance. Check if the congestion window
* overflowed. Put the task to sleep if this is the case.
*/
static int
__xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task)
{
struct rpc_rqst *req = task->tk_rqstp;
if (req->rq_cong)
return 1;
dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n",
task->tk_pid, xprt->cong, xprt->cwnd);
if (RPCXPRT_CONGESTED(xprt))
return 0;
req->rq_cong = 1;
xprt->cong += RPC_CWNDSCALE;
return 1;
}
static void
__xprt_lock_write_next(struct rpc_xprt *xprt)
{
struct rpc_task *task;
if (xprt->snd_task)
return;
task = rpc_wake_up_next(&xprt->resend);
if (!task) {
if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
return;
task = rpc_wake_up_next(&xprt->sending);
if (!task)
return;
}
if (xprt->nocong || __xprt_get_cong(xprt, task))
xprt->snd_task = task;
}
static void
__xprt_lock_write_next(struct rpc_xprt *xprt)
{
struct rpc_task *task;
if (xprt->snd_task)
return;
task = rpc_wake_up_next(&xprt->resend);
if (!task) {
if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
return;
task = rpc_wake_up_next(&xprt->sending);
if (!task)
return;
}
if (xprt->nocong || __xprt_get_cong(xprt, task)) {
struct rpc_rqst *req = task->tk_rqstp;
xprt->snd_task = task;
if (req) {
req->rq_bytes_sent = 0;
req->rq_ntrans++;
}
}
}