From cf9946cd6144410ced00d52586ff5a2cb4868fc5 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 6 Aug 2018 12:55:34 -0400 Subject: [PATCH] SUNRPC: Refactor the transport request pinning We are going to need to pin for both send and receive. Signed-off-by: Trond Myklebust --- include/linux/sunrpc/sched.h | 3 +-- include/linux/sunrpc/xprt.h | 1 + net/sunrpc/xprt.c | 43 +++++++++++++++++++++++-------------------- 3 files changed, 25 insertions(+), 22 deletions(-) diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h index 9e655df70131..8062ce6b18e5 100644 --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -142,8 +142,7 @@ struct rpc_task_setup { #define RPC_TASK_ACTIVE 2 #define RPC_TASK_NEED_XMIT 3 #define RPC_TASK_NEED_RECV 4 -#define RPC_TASK_MSG_RECV 5 -#define RPC_TASK_MSG_RECV_WAIT 6 +#define RPC_TASK_MSG_PIN_WAIT 5 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate) diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 3d80524e92d6..bd743c51a865 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -103,6 +103,7 @@ struct rpc_rqst { /* A cookie used to track the state of the transport connection */ + atomic_t rq_pin; /* * Partial send handling diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index 45d580cd93ac..649a40cfae6d 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -847,16 +847,22 @@ struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) } EXPORT_SYMBOL_GPL(xprt_lookup_rqst); +static bool +xprt_is_pinned_rqst(struct rpc_rqst *req) +{ + return atomic_read(&req->rq_pin) != 0; +} + /** * xprt_pin_rqst - Pin a request on the transport receive list * @req: Request to pin * * Caller must ensure this is atomic with the call to xprt_lookup_rqst() - * so should be holding the xprt transport lock. + * so should be holding the xprt receive lock. */ void xprt_pin_rqst(struct rpc_rqst *req) { - set_bit(RPC_TASK_MSG_RECV, &req->rq_task->tk_runstate); + atomic_inc(&req->rq_pin); } EXPORT_SYMBOL_GPL(xprt_pin_rqst); @@ -864,31 +870,22 @@ EXPORT_SYMBOL_GPL(xprt_pin_rqst); * xprt_unpin_rqst - Unpin a request on the transport receive list * @req: Request to pin * - * Caller should be holding the xprt transport lock. + * Caller should be holding the xprt receive lock. */ void xprt_unpin_rqst(struct rpc_rqst *req) { - struct rpc_task *task = req->rq_task; - - clear_bit(RPC_TASK_MSG_RECV, &task->tk_runstate); - if (test_bit(RPC_TASK_MSG_RECV_WAIT, &task->tk_runstate)) - wake_up_bit(&task->tk_runstate, RPC_TASK_MSG_RECV); + if (!test_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate)) { + atomic_dec(&req->rq_pin); + return; + } + if (atomic_dec_and_test(&req->rq_pin)) + wake_up_var(&req->rq_pin); } EXPORT_SYMBOL_GPL(xprt_unpin_rqst); static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) -__must_hold(&req->rq_xprt->recv_lock) { - struct rpc_task *task = req->rq_task; - - if (task && test_bit(RPC_TASK_MSG_RECV, &task->tk_runstate)) { - spin_unlock(&req->rq_xprt->recv_lock); - set_bit(RPC_TASK_MSG_RECV_WAIT, &task->tk_runstate); - wait_on_bit(&task->tk_runstate, RPC_TASK_MSG_RECV, - TASK_UNINTERRUPTIBLE); - clear_bit(RPC_TASK_MSG_RECV_WAIT, &task->tk_runstate); - spin_lock(&req->rq_xprt->recv_lock); - } + wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); } /** @@ -1388,7 +1385,13 @@ void xprt_release(struct rpc_task *task) spin_lock(&xprt->recv_lock); if (!list_empty(&req->rq_list)) { list_del_init(&req->rq_list); - xprt_wait_on_pinned_rqst(req); + if (xprt_is_pinned_rqst(req)) { + set_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate); + spin_unlock(&xprt->recv_lock); + xprt_wait_on_pinned_rqst(req); + spin_lock(&xprt->recv_lock); + clear_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate); + } } spin_unlock(&xprt->recv_lock); spin_lock_bh(&xprt->transport_lock); -- 2.11.0