svcrdma: Increase the default connection credit limit

Reduce queuing on clients by allowing more credits by default.

64 is the default NFSv4.1 slot table size on Linux clients. This
size prevents the credit limit from putting RPC requests to sleep
again after they have already slept waiting for a session slot.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h
index fd78f78df5c662b61430b93858bb5295fec45480..e6e26918504c1ee6644b52604bd25c223303a3ce 100644 (file)
--- a/include/linux/sunrpc/svc_rdma.h
+++ b/include/linux/sunrpc/svc_rdma.h
@@ -113,13 +113,14 @@ struct svcxprt_rdma {
 /* sc_flags */
 #define RDMAXPRT_CONN_PENDING  3
 
-#define RPCRDMA_LISTEN_BACKLOG  10
-#define RPCRDMA_MAX_REQUESTS    32
-
-/* Typical ULP usage of BC requests is NFSv4.1 backchannel. Our
- * current NFSv4.1 implementation supports one backchannel slot.
+/*
+ * Default connection parameters
  */
-#define RPCRDMA_MAX_BC_REQUESTS        2
+enum {
+       RPCRDMA_LISTEN_BACKLOG  = 10,
+       RPCRDMA_MAX_REQUESTS    = 64,
+       RPCRDMA_MAX_BC_REQUESTS = 2,
+};
 
 #define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD