diff options
author | Chuck Lever <chuck.lever@oracle.com> | 2017-08-24 00:05:58 +0300 |
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committer | Trond Myklebust <trond.myklebust@primarydata.com> | 2017-09-06 01:27:07 +0300 |
commit | 9590d083c1bb1419b7992609d1a0a3e3517d3893 (patch) | |
tree | ed285e1635c2232d66d432835fc13890ef209718 /net/sunrpc/xprtrdma/xprt_rdma.h | |
parent | f9773b22a27a4234f436c9570afd62d905e00a13 (diff) | |
download | linux-9590d083c1bb1419b7992609d1a0a3e3517d3893.tar.xz |
xprtrdma: Use xprt_pin_rqst in rpcrdma_reply_handler
Adopt the use of xprt_pin_rqst to eliminate contention between
Call-side users of rb_lock and the use of rb_lock in
rpcrdma_reply_handler.
This replaces the mechanism introduced in 431af645cf66 ("xprtrdma:
Fix client lock-up after application signal fires").
Use recv_lock to quickly find the completing rqst, pin it, then
drop the lock. At that point invalidation and pull-up of the Reply
XDR can be done. Both are often expensive operations.
Finally, take recv_lock again to signal completion to the RPC
layer. It also protects adjustment of "cwnd".
This greatly reduces the amount of time a lock is held by the
reply handler. Comparing lock_stat results shows a marked decrease
in contention on rb_lock and recv_lock.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[trond.myklebust@primarydata.com: Remove call to rpcrdma_buffer_put() from
the "out_norqst:" path in rpcrdma_reply_handler.]
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/xprt_rdma.h')
-rw-r--r-- | net/sunrpc/xprtrdma/xprt_rdma.h | 30 |
1 files changed, 0 insertions, 30 deletions
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 45dab2475c99..e26a97d2f922 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -340,7 +340,6 @@ enum { struct rpcrdma_buffer; struct rpcrdma_req { struct list_head rl_list; - __be32 rl_xid; unsigned int rl_mapped_sges; unsigned int rl_connect_cookie; struct rpcrdma_buffer *rl_buffer; @@ -404,7 +403,6 @@ struct rpcrdma_buffer { int rb_send_count, rb_recv_count; struct list_head rb_send_bufs; struct list_head rb_recv_bufs; - struct list_head rb_pending; u32 rb_max_requests; atomic_t rb_credits; /* most recent credit grant */ @@ -557,34 +555,6 @@ void rpcrdma_destroy_req(struct rpcrdma_req *); int rpcrdma_buffer_create(struct rpcrdma_xprt *); void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); -static inline void -rpcrdma_insert_req(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req) -{ - spin_lock(&buffers->rb_lock); - if (list_empty(&req->rl_list)) - list_add_tail(&req->rl_list, &buffers->rb_pending); - spin_unlock(&buffers->rb_lock); -} - -static inline struct rpcrdma_req * -rpcrdma_lookup_req_locked(struct rpcrdma_buffer *buffers, __be32 xid) -{ - struct rpcrdma_req *pos; - - list_for_each_entry(pos, &buffers->rb_pending, rl_list) - if (pos->rl_xid == xid) - return pos; - return NULL; -} - -static inline void -rpcrdma_remove_req(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req) -{ - spin_lock(&buffers->rb_lock); - list_del(&req->rl_list); - spin_unlock(&buffers->rb_lock); -} - struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *); void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *); struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); |