[PATCH] sunrpc: drop BKL around wrap and unwrap

[J. Bruce Fields]

We don't need the BKL when wrapping and unwrapping; and experiments by Avishay
Traeger have found that permitting multiple encryption and decryption
operations to proceed in parallel can provide significant performance
improvements.

Signed-off-by: J. Bruce Fields <bfields at citi.umich.edu>
Cc: Avishay Traeger <atraeger at cs.sunysb.edu>
---
 net/sunrpc/auth_gss/auth_gss.c |   10 ++++++++++
 net/sunrpc/clnt.c              |    4 ----
 2 files changed, 10 insertions(+), 4 deletions(-)

I think you suggested sending this to Chuck, since he's working on other
BKL removal projects.  But that appears to be on the back burner, and
this is ready to go in now, so he suggested you should just take it....

--b.

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 4e4ccc5..a001973 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -917,7 +917,9 @@ gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 	offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
 	*p++ = htonl(rqstp->rq_seqno);
 
+	lock_kernel();
 	status = encode(rqstp, p, obj);
+	unlock_kernel();
 	if (status)
 		return status;
 
@@ -1011,7 +1013,9 @@ gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 	offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
 	*p++ = htonl(rqstp->rq_seqno);
 
+	lock_kernel();
 	status = encode(rqstp, p, obj);
+	unlock_kernel();
 	if (status)
 		return status;
 
@@ -1070,12 +1074,16 @@ gss_wrap_req(struct rpc_task *task,
 		/* The spec seems a little ambiguous here, but I think that not
 		 * wrapping context destruction requests makes the most sense.
 		 */
+		lock_kernel();
 		status = encode(rqstp, p, obj);
+		unlock_kernel();
 		goto out;
 	}
 	switch (gss_cred->gc_service) {
 		case RPC_GSS_SVC_NONE:
+			lock_kernel();
 			status = encode(rqstp, p, obj);
+			unlock_kernel();
 			break;
 		case RPC_GSS_SVC_INTEGRITY:
 			status = gss_wrap_req_integ(cred, ctx, encode,
@@ -1191,7 +1199,9 @@ gss_unwrap_resp(struct rpc_task *task,
 	task->tk_auth->au_rslack = task->tk_auth->au_verfsize + (p - savedp)
 						+ (savedlen - head->iov_len);
 out_decode:
+	lock_kernel();
 	status = decode(rqstp, p, obj);
+	unlock_kernel();
 out:
 	gss_put_ctx(ctx);
 	dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid,
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index d8fbee4..2534690 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -843,10 +843,8 @@ call_encode(struct rpc_task *task)
 	if (encode == NULL)
 		return;
 
-	lock_kernel();
 	task->tk_status = rpcauth_wrap_req(task, encode, req, p,
 			task->tk_msg.rpc_argp);
-	unlock_kernel();
 	if (task->tk_status == -ENOMEM) {
 		/* XXX: Is this sane? */
 		rpc_delay(task, 3*HZ);
@@ -1177,10 +1175,8 @@ call_decode(struct rpc_task *task)
 	task->tk_action = rpc_exit_task;
 
 	if (decode) {
-		lock_kernel();
 		task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
 						      task->tk_msg.rpc_resp);
-		unlock_kernel();
 	}
 	dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
 			task->tk_status);
-- 
1.5.3.rc0.63.gc956