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Diffstat (limited to 'net/sunrpc/xprt.c')
-rw-r--r--net/sunrpc/xprt.c257
1 files changed, 170 insertions, 87 deletions
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index ce5eb68a9664..9b6a4d1ea8f8 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -62,6 +62,7 @@
/*
* Local functions
*/
+static void xprt_init(struct rpc_xprt *xprt, struct net *net);
static void xprt_request_init(struct rpc_task *, struct rpc_xprt *);
static void xprt_connect_status(struct rpc_task *task);
static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *);
@@ -191,10 +192,10 @@ EXPORT_SYMBOL_GPL(xprt_load_transport);
* transport connects from colliding with writes. No congestion control
* is provided.
*/
-int xprt_reserve_xprt(struct rpc_task *task)
+int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
{
struct rpc_rqst *req = task->tk_rqstp;
- struct rpc_xprt *xprt = req->rq_xprt;
+ int priority;
if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
if (task == xprt->snd_task)
@@ -202,8 +203,10 @@ int xprt_reserve_xprt(struct rpc_task *task)
goto out_sleep;
}
xprt->snd_task = task;
- req->rq_bytes_sent = 0;
- req->rq_ntrans++;
+ if (req != NULL) {
+ req->rq_bytes_sent = 0;
+ req->rq_ntrans++;
+ }
return 1;
@@ -212,10 +215,13 @@ out_sleep:
task->tk_pid, xprt);
task->tk_timeout = 0;
task->tk_status = -EAGAIN;
- if (req->rq_ntrans)
- rpc_sleep_on(&xprt->resend, task, NULL);
+ if (req == NULL)
+ priority = RPC_PRIORITY_LOW;
+ else if (!req->rq_ntrans)
+ priority = RPC_PRIORITY_NORMAL;
else
- rpc_sleep_on(&xprt->sending, task, NULL);
+ priority = RPC_PRIORITY_HIGH;
+ rpc_sleep_on_priority(&xprt->sending, task, NULL, priority);
return 0;
}
EXPORT_SYMBOL_GPL(xprt_reserve_xprt);
@@ -239,22 +245,24 @@ static void xprt_clear_locked(struct rpc_xprt *xprt)
* integrated into the decision of whether a request is allowed to be
* woken up and given access to the transport.
*/
-int xprt_reserve_xprt_cong(struct rpc_task *task)
+int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task)
{
- struct rpc_xprt *xprt = task->tk_xprt;
struct rpc_rqst *req = task->tk_rqstp;
+ int priority;
if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
if (task == xprt->snd_task)
return 1;
goto out_sleep;
}
+ if (req == NULL) {
+ xprt->snd_task = task;
+ return 1;
+ }
if (__xprt_get_cong(xprt, task)) {
xprt->snd_task = task;
- if (req) {
- req->rq_bytes_sent = 0;
- req->rq_ntrans++;
- }
+ req->rq_bytes_sent = 0;
+ req->rq_ntrans++;
return 1;
}
xprt_clear_locked(xprt);
@@ -262,10 +270,13 @@ out_sleep:
dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt);
task->tk_timeout = 0;
task->tk_status = -EAGAIN;
- if (req && req->rq_ntrans)
- rpc_sleep_on(&xprt->resend, task, NULL);
+ if (req == NULL)
+ priority = RPC_PRIORITY_LOW;
+ else if (!req->rq_ntrans)
+ priority = RPC_PRIORITY_NORMAL;
else
- rpc_sleep_on(&xprt->sending, task, NULL);
+ priority = RPC_PRIORITY_HIGH;
+ rpc_sleep_on_priority(&xprt->sending, task, NULL, priority);
return 0;
}
EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong);
@@ -275,7 +286,7 @@ static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
int retval;
spin_lock_bh(&xprt->transport_lock);
- retval = xprt->ops->reserve_xprt(task);
+ retval = xprt->ops->reserve_xprt(xprt, task);
spin_unlock_bh(&xprt->transport_lock);
return retval;
}
@@ -288,12 +299,9 @@ static void __xprt_lock_write_next(struct rpc_xprt *xprt)
if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
return;
- task = rpc_wake_up_next(&xprt->resend);
- if (!task) {
- task = rpc_wake_up_next(&xprt->sending);
- if (!task)
- goto out_unlock;
- }
+ task = rpc_wake_up_next(&xprt->sending);
+ if (task == NULL)
+ goto out_unlock;
req = task->tk_rqstp;
xprt->snd_task = task;
@@ -310,24 +318,25 @@ out_unlock:
static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt)
{
struct rpc_task *task;
+ struct rpc_rqst *req;
if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
return;
if (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;
+ task = rpc_wake_up_next(&xprt->sending);
+ if (task == NULL)
+ goto out_unlock;
+
+ req = task->tk_rqstp;
+ if (req == NULL) {
+ xprt->snd_task = task;
+ return;
}
if (__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++;
- }
+ req->rq_bytes_sent = 0;
+ req->rq_ntrans++;
return;
}
out_unlock:
@@ -852,7 +861,7 @@ int xprt_prepare_transmit(struct rpc_task *task)
err = req->rq_reply_bytes_recvd;
goto out_unlock;
}
- if (!xprt->ops->reserve_xprt(task))
+ if (!xprt->ops->reserve_xprt(xprt, task))
err = -EAGAIN;
out_unlock:
spin_unlock_bh(&xprt->transport_lock);
@@ -928,28 +937,66 @@ void xprt_transmit(struct rpc_task *task)
spin_unlock_bh(&xprt->transport_lock);
}
+static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags)
+{
+ struct rpc_rqst *req = ERR_PTR(-EAGAIN);
+
+ if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs))
+ goto out;
+ req = kzalloc(sizeof(struct rpc_rqst), gfp_flags);
+ if (req != NULL)
+ goto out;
+ atomic_dec(&xprt->num_reqs);
+ req = ERR_PTR(-ENOMEM);
+out:
+ return req;
+}
+
+static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
+{
+ if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) {
+ kfree(req);
+ return true;
+ }
+ return false;
+}
+
static void xprt_alloc_slot(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
+ struct rpc_rqst *req;
- task->tk_status = 0;
- if (task->tk_rqstp)
- return;
if (!list_empty(&xprt->free)) {
- struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list);
- list_del_init(&req->rq_list);
- task->tk_rqstp = req;
- xprt_request_init(task, xprt);
- return;
+ req = list_entry(xprt->free.next, struct rpc_rqst, rq_list);
+ list_del(&req->rq_list);
+ goto out_init_req;
+ }
+ req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT);
+ if (!IS_ERR(req))
+ goto out_init_req;
+ switch (PTR_ERR(req)) {
+ case -ENOMEM:
+ rpc_delay(task, HZ >> 2);
+ dprintk("RPC: dynamic allocation of request slot "
+ "failed! Retrying\n");
+ break;
+ case -EAGAIN:
+ rpc_sleep_on(&xprt->backlog, task, NULL);
+ dprintk("RPC: waiting for request slot\n");
}
- dprintk("RPC: waiting for request slot\n");
task->tk_status = -EAGAIN;
- task->tk_timeout = 0;
- rpc_sleep_on(&xprt->backlog, task, NULL);
+ return;
+out_init_req:
+ task->tk_status = 0;
+ task->tk_rqstp = req;
+ xprt_request_init(task, xprt);
}
static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
{
+ if (xprt_dynamic_free_slot(xprt, req))
+ return;
+
memset(req, 0, sizeof(*req)); /* mark unused */
spin_lock(&xprt->reserve_lock);
@@ -958,25 +1005,49 @@ static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
spin_unlock(&xprt->reserve_lock);
}
-struct rpc_xprt *xprt_alloc(struct net *net, int size, int max_req)
+static void xprt_free_all_slots(struct rpc_xprt *xprt)
+{
+ struct rpc_rqst *req;
+ while (!list_empty(&xprt->free)) {
+ req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list);
+ list_del(&req->rq_list);
+ kfree(req);
+ }
+}
+
+struct rpc_xprt *xprt_alloc(struct net *net, size_t size,
+ unsigned int num_prealloc,
+ unsigned int max_alloc)
{
struct rpc_xprt *xprt;
+ struct rpc_rqst *req;
+ int i;
xprt = kzalloc(size, GFP_KERNEL);
if (xprt == NULL)
goto out;
- atomic_set(&xprt->count, 1);
- xprt->max_reqs = max_req;
- xprt->slot = kcalloc(max_req, sizeof(struct rpc_rqst), GFP_KERNEL);
- if (xprt->slot == NULL)
+ xprt_init(xprt, net);
+
+ for (i = 0; i < num_prealloc; i++) {
+ req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL);
+ if (!req)
+ break;
+ list_add(&req->rq_list, &xprt->free);
+ }
+ if (i < num_prealloc)
goto out_free;
+ if (max_alloc > num_prealloc)
+ xprt->max_reqs = max_alloc;
+ else
+ xprt->max_reqs = num_prealloc;
+ xprt->min_reqs = num_prealloc;
+ atomic_set(&xprt->num_reqs, num_prealloc);
- xprt->xprt_net = get_net(net);
return xprt;
out_free:
- kfree(xprt);
+ xprt_free(xprt);
out:
return NULL;
}
@@ -985,7 +1056,7 @@ EXPORT_SYMBOL_GPL(xprt_alloc);
void xprt_free(struct rpc_xprt *xprt)
{
put_net(xprt->xprt_net);
- kfree(xprt->slot);
+ xprt_free_all_slots(xprt);
kfree(xprt);
}
EXPORT_SYMBOL_GPL(xprt_free);
@@ -1001,10 +1072,24 @@ void xprt_reserve(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
- task->tk_status = -EIO;
+ task->tk_status = 0;
+ if (task->tk_rqstp != NULL)
+ return;
+
+ /* Note: grabbing the xprt_lock_write() here is not strictly needed,
+ * but ensures that we throttle new slot allocation if the transport
+ * is congested (e.g. if reconnecting or if we're out of socket
+ * write buffer space).
+ */
+ task->tk_timeout = 0;
+ task->tk_status = -EAGAIN;
+ if (!xprt_lock_write(xprt, task))
+ return;
+
spin_lock(&xprt->reserve_lock);
xprt_alloc_slot(task);
spin_unlock(&xprt->reserve_lock);
+ xprt_release_write(xprt, task);
}
static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt)
@@ -1021,6 +1106,7 @@ static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt)
{
struct rpc_rqst *req = task->tk_rqstp;
+ INIT_LIST_HEAD(&req->rq_list);
req->rq_timeout = task->tk_client->cl_timeout->to_initval;
req->rq_task = task;
req->rq_xprt = xprt;
@@ -1073,6 +1159,34 @@ void xprt_release(struct rpc_task *task)
xprt_free_bc_request(req);
}
+static void xprt_init(struct rpc_xprt *xprt, struct net *net)
+{
+ atomic_set(&xprt->count, 1);
+
+ spin_lock_init(&xprt->transport_lock);
+ spin_lock_init(&xprt->reserve_lock);
+
+ INIT_LIST_HEAD(&xprt->free);
+ INIT_LIST_HEAD(&xprt->recv);
+#if defined(CONFIG_SUNRPC_BACKCHANNEL)
+ spin_lock_init(&xprt->bc_pa_lock);
+ INIT_LIST_HEAD(&xprt->bc_pa_list);
+#endif /* CONFIG_SUNRPC_BACKCHANNEL */
+
+ xprt->last_used = jiffies;
+ xprt->cwnd = RPC_INITCWND;
+ xprt->bind_index = 0;
+
+ rpc_init_wait_queue(&xprt->binding, "xprt_binding");
+ rpc_init_wait_queue(&xprt->pending, "xprt_pending");
+ rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending");
+ rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog");
+
+ xprt_init_xid(xprt);
+
+ xprt->xprt_net = get_net(net);
+}
+
/**
* xprt_create_transport - create an RPC transport
* @args: rpc transport creation arguments
@@ -1081,7 +1195,6 @@ void xprt_release(struct rpc_task *task)
struct rpc_xprt *xprt_create_transport(struct xprt_create *args)
{
struct rpc_xprt *xprt;
- struct rpc_rqst *req;
struct xprt_class *t;
spin_lock(&xprt_list_lock);
@@ -1100,46 +1213,17 @@ found:
if (IS_ERR(xprt)) {
dprintk("RPC: xprt_create_transport: failed, %ld\n",
-PTR_ERR(xprt));
- return xprt;
+ goto out;
}
- if (test_and_set_bit(XPRT_INITIALIZED, &xprt->state))
- /* ->setup returned a pre-initialized xprt: */
- return xprt;
-
- spin_lock_init(&xprt->transport_lock);
- spin_lock_init(&xprt->reserve_lock);
-
- INIT_LIST_HEAD(&xprt->free);
- INIT_LIST_HEAD(&xprt->recv);
-#if defined(CONFIG_NFS_V4_1)
- spin_lock_init(&xprt->bc_pa_lock);
- INIT_LIST_HEAD(&xprt->bc_pa_list);
-#endif /* CONFIG_NFS_V4_1 */
-
INIT_WORK(&xprt->task_cleanup, xprt_autoclose);
if (xprt_has_timer(xprt))
setup_timer(&xprt->timer, xprt_init_autodisconnect,
(unsigned long)xprt);
else
init_timer(&xprt->timer);
- xprt->last_used = jiffies;
- xprt->cwnd = RPC_INITCWND;
- xprt->bind_index = 0;
-
- rpc_init_wait_queue(&xprt->binding, "xprt_binding");
- rpc_init_wait_queue(&xprt->pending, "xprt_pending");
- rpc_init_wait_queue(&xprt->sending, "xprt_sending");
- rpc_init_wait_queue(&xprt->resend, "xprt_resend");
- rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog");
-
- /* initialize free list */
- for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--)
- list_add(&req->rq_list, &xprt->free);
-
- xprt_init_xid(xprt);
-
dprintk("RPC: created transport %p with %u slots\n", xprt,
xprt->max_reqs);
+out:
return xprt;
}
@@ -1157,7 +1241,6 @@ static void xprt_destroy(struct rpc_xprt *xprt)
rpc_destroy_wait_queue(&xprt->binding);
rpc_destroy_wait_queue(&xprt->pending);
rpc_destroy_wait_queue(&xprt->sending);
- rpc_destroy_wait_queue(&xprt->resend);
rpc_destroy_wait_queue(&xprt->backlog);
cancel_work_sync(&xprt->task_cleanup);
/*