Merge pull request #10344 from xiexingguo:xxg-wip-pipe-2016-07-19-02

msg/simple: apply prefetch policy more precisely

Reviewed-by: Greg Farnum <gfarnum@redhat.com>
Conflicts:
	src/msg/simple/Pipe.cc (removed unneeded cast)

diff --cc src/msg/simple/Pipe.cc
index e00965eba10f49a71605ce40ba0bae8add55efc1,4a6bb0173daecd94f3a6c66c5a1a3eeb7064d974..a1470c4e1247f52b0acd1bbee26fe9ec3adf9e46
--- 1/src/msg/simple/Pipe.cc
--- 2/src/msg/simple/Pipe.cc
+++ b/src/msg/simple/Pipe.cc
@@@ -2554,7 -2554,7 +2554,7 @@@ ssize_t Pipe::buffered_recv(char *buf, 
  
    /* nothing left in the prefetch buffer */
  
-   if (len > recv_max_prefetch) {
 -  if (left > (size_t)recv_max_prefetch) {
++  if (left > recv_max_prefetch) {
      /* this was a large read, we don't prefetch for these */
      ssize_t ret = do_recv(buf, left, flags );
      if (ret < 0) {