Doug / smarc-fsl-linux-kernel

Download as
Browse Code ยป

Commit 43ac3f2961b8616da26114ec6dc76ac2a61f76ad

Authored by Trond Myklebust
1 parent c42de9dd67
Exists in master and in 7 other branches imx_3.0.35_4.1.0, imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga, smarc-l5.0.0_1.0.0-ga

SUNRPC: Fix memory barriers for req->rq_received 

We need to ensure that all writes to the XDR buffers are done before
req->rq_received is visible to other processors.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Showing 2 changed files with 7 additions and 1 deletions Side-by-side Diff

... ... @@ -1069,6 +1069,11 @@
1069 1069 return;
1070 1070 }
1071 1071  
  1072 + /*
  1073 + * Ensure that we see all writes made by xprt_complete_rqst()
  1074 + * before it changed req->rq_received.
  1075 + */
  1076 + smp_rmb();
1072 1077 req->rq_rcv_buf.len = req->rq_private_buf.len;
1073 1078  
1074 1079 /* Check that the softirq receive buffer is valid */
... ... @@ -651,6 +651,8 @@
651 651 task->tk_rtt = (long)jiffies - req->rq_xtime;
652 652  
653 653 list_del_init(&req->rq_list);
  654 + /* Ensure all writes are done before we update req->rq_received */
  655 + smp_wmb();
654 656 req->rq_received = req->rq_private_buf.len = copied;
655 657 rpc_wake_up_task(task);
656 658 }
... ... @@ -727,7 +729,6 @@
727 729  
728 730 dprintk("RPC: %4d xprt_transmit(%u)\n", task->tk_pid, req->rq_slen);
729 731  
730   - smp_rmb();
731 732 if (!req->rq_received) {
732 733 if (list_empty(&req->rq_list)) {
733 734 spin_lock_bh(&xprt->transport_lock);