os: reset result code to errno for better tracing

Signed-off-by: xie xingguo <xie.xingguo@zte.com.cn>

diff --git a/src/os/kstore/KStore.cc b/src/os/kstore/KStore.cc
index 5d05fa15d12bd8ac6f5135dd2e3467a2ce0e1351..ec7b5e14e493c1956dfccabc0906d69d49cc2f67 100644 (file)
--- a/src/os/kstore/KStore.cc
+++ b/src/os/kstore/KStore.cc
@@ -754,6 +754,7 @@ int KStore::_write_fsid()
   }
   r = ::fsync(fsid_fd);
   if (r < 0) {
+    r = -errno;
     derr << __func__ << " fsid fsync failed: " << cpp_strerror(r) << dendl;
     return r;
   }