SUNRPC: Start the first major timeout calculation at task creation
authorTrond Myklebust <trondmy@gmail.com>
Sun, 7 Apr 2019 17:58:56 +0000 (13:58 -0400)
committerAnna Schumaker <Anna.Schumaker@Netapp.com>
Thu, 25 Apr 2019 18:18:13 +0000 (14:18 -0400)
When calculating the major timeout for a new task, when we know that the
connection has been broken, use the task->tk_start to ensure that we also
take into account the time spent waiting for a slot or session slot. This
ensures that we fail over soft requests relatively quickly once the
connection has actually been broken, and the first requests have
started to fail.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
net/sunrpc/xprt.c

index 642cc0f..bc1c824 100644 (file)
@@ -569,18 +569,44 @@ bool xprt_write_space(struct rpc_xprt *xprt)
 }
 EXPORT_SYMBOL_GPL(xprt_write_space);
 
-static void xprt_reset_majortimeo(struct rpc_rqst *req)
+static unsigned long xprt_abs_ktime_to_jiffies(ktime_t abstime)
+{
+       s64 delta = ktime_to_ns(ktime_get() - abstime);
+       return likely(delta >= 0) ?
+               jiffies - nsecs_to_jiffies(delta) :
+               jiffies + nsecs_to_jiffies(-delta);
+}
+
+static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req)
 {
        const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout;
+       unsigned long majortimeo = req->rq_timeout;
 
-       req->rq_majortimeo = req->rq_timeout;
        if (to->to_exponential)
-               req->rq_majortimeo <<= to->to_retries;
+               majortimeo <<= to->to_retries;
+       else
+               majortimeo += to->to_increment * to->to_retries;
+       if (majortimeo > to->to_maxval || majortimeo == 0)
+               majortimeo = to->to_maxval;
+       return majortimeo;
+}
+
+static void xprt_reset_majortimeo(struct rpc_rqst *req)
+{
+       req->rq_majortimeo += xprt_calc_majortimeo(req);
+}
+
+static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req)
+{
+       unsigned long time_init;
+       struct rpc_xprt *xprt = req->rq_xprt;
+
+       if (likely(xprt && xprt_connected(xprt)))
+               time_init = jiffies;
        else
-               req->rq_majortimeo += to->to_increment * to->to_retries;
-       if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0)
-               req->rq_majortimeo = to->to_maxval;
-       req->rq_majortimeo += jiffies;
+               time_init = xprt_abs_ktime_to_jiffies(task->tk_start);
+       req->rq_timeout = task->tk_client->cl_timeout->to_initval;
+       req->rq_majortimeo = time_init + xprt_calc_majortimeo(req);
 }
 
 /**
@@ -997,7 +1023,6 @@ xprt_request_enqueue_receive(struct rpc_task *task)
        set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate);
        spin_unlock(&xprt->queue_lock);
 
-       xprt_reset_majortimeo(req);
        /* Turn off autodisconnect */
        del_singleshot_timer_sync(&xprt->timer);
 }
@@ -1631,7 +1656,6 @@ xprt_request_init(struct rpc_task *task)
        struct rpc_xprt *xprt = task->tk_xprt;
        struct rpc_rqst *req = task->tk_rqstp;
 
-       req->rq_timeout = task->tk_client->cl_timeout->to_initval;
        req->rq_task    = task;
        req->rq_xprt    = xprt;
        req->rq_buffer  = NULL;
@@ -1644,7 +1668,7 @@ xprt_request_init(struct rpc_task *task)
        req->rq_snd_buf.bvec = NULL;
        req->rq_rcv_buf.bvec = NULL;
        req->rq_release_snd_buf = NULL;
-       xprt_reset_majortimeo(req);
+       xprt_init_majortimeo(task, req);
        dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid,
                        req, ntohl(req->rq_xid));
 }