diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index fefcba982415a5417c630d71c48ebb7e53a34d32..799cce6cbe45e89f4030d4cd1a17a15b56cf3cf2 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -51,6 +51,7 @@ #include #include #include +#include #include #include /* try_module_get()/module_put() */ @@ -923,7 +924,7 @@ rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt) } INIT_LIST_HEAD(&buf->rb_recv_bufs); - for (i = 0; i < buf->rb_max_requests + 2; i++) { + for (i = 0; i < buf->rb_max_requests + RPCRDMA_MAX_BC_REQUESTS; i++) { struct rpcrdma_rep *rep; rep = rpcrdma_create_rep(r_xprt); @@ -1018,6 +1019,7 @@ rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf) rep = rpcrdma_buffer_get_rep_locked(buf); rpcrdma_destroy_rep(ia, rep); } + buf->rb_send_count = 0; spin_lock(&buf->rb_reqslock); while (!list_empty(&buf->rb_allreqs)) { @@ -1032,6 +1034,7 @@ rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf) spin_lock(&buf->rb_reqslock); } spin_unlock(&buf->rb_reqslock); + buf->rb_recv_count = 0; rpcrdma_destroy_mrs(buf); } @@ -1074,6 +1077,23 @@ rpcrdma_put_mw(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mw *mw) spin_unlock(&buf->rb_mwlock); } +static struct rpcrdma_rep * +rpcrdma_buffer_get_rep(struct rpcrdma_buffer *buffers) +{ + /* If an RPC previously completed without a reply (say, a + * credential problem or a soft timeout occurs) then hold off + * on supplying more Receive buffers until the number of new + * pending RPCs catches up to the number of posted Receives. + */ + if (unlikely(buffers->rb_send_count < buffers->rb_recv_count)) + return NULL; + + if (unlikely(list_empty(&buffers->rb_recv_bufs))) + return NULL; + buffers->rb_recv_count++; + return rpcrdma_buffer_get_rep_locked(buffers); +} + /* * Get a set of request/reply buffers. * @@ -1087,10 +1107,9 @@ rpcrdma_buffer_get(struct rpcrdma_buffer *buffers) spin_lock(&buffers->rb_lock); if (list_empty(&buffers->rb_send_bufs)) goto out_reqbuf; + buffers->rb_send_count++; req = rpcrdma_buffer_get_req_locked(buffers); - if (list_empty(&buffers->rb_recv_bufs)) - goto out_repbuf; - req->rl_reply = rpcrdma_buffer_get_rep_locked(buffers); + req->rl_reply = rpcrdma_buffer_get_rep(buffers); spin_unlock(&buffers->rb_lock); return req; @@ -1098,11 +1117,6 @@ rpcrdma_buffer_get(struct rpcrdma_buffer *buffers) spin_unlock(&buffers->rb_lock); pr_warn("RPC: %s: out of request buffers\n", __func__); return NULL; -out_repbuf: - spin_unlock(&buffers->rb_lock); - pr_warn("RPC: %s: out of reply buffers\n", __func__); - req->rl_reply = NULL; - return req; } /* @@ -1119,9 +1133,12 @@ rpcrdma_buffer_put(struct rpcrdma_req *req) req->rl_reply = NULL; spin_lock(&buffers->rb_lock); + buffers->rb_send_count--; list_add_tail(&req->rl_free, &buffers->rb_send_bufs); - if (rep) + if (rep) { + buffers->rb_recv_count--; list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs); + } spin_unlock(&buffers->rb_lock); } @@ -1135,8 +1152,7 @@ rpcrdma_recv_buffer_get(struct rpcrdma_req *req) struct rpcrdma_buffer *buffers = req->rl_buffer; spin_lock(&buffers->rb_lock); - if (!list_empty(&buffers->rb_recv_bufs)) - req->rl_reply = rpcrdma_buffer_get_rep_locked(buffers); + req->rl_reply = rpcrdma_buffer_get_rep(buffers); spin_unlock(&buffers->rb_lock); } @@ -1150,6 +1166,7 @@ rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep) struct rpcrdma_buffer *buffers = &rep->rr_rxprt->rx_buf; spin_lock(&buffers->rb_lock); + buffers->rb_recv_count--; list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs); spin_unlock(&buffers->rb_lock); } diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 670fad57153a109b5f8d14ac9cd3733e874c81d3..a71b0f5897d8721ee8edaed291388c34f61d3cee 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -321,6 +321,7 @@ struct rpcrdma_buffer { char *rb_pool; spinlock_t rb_lock; /* protect buf lists */ + int rb_send_count, rb_recv_count; struct list_head rb_send_bufs; struct list_head rb_recv_bufs; u32 rb_max_requests;