mount switch to ordered lock requests

weed/mount/weedfs_file_sync.go

@@ -7,6 +7,7 @@ import (
 	"github.com/seaweedfs/seaweedfs/weed/filer"
 	"github.com/seaweedfs/seaweedfs/weed/glog"
 	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
+	"github.com/seaweedfs/seaweedfs/weed/util"
 	"syscall"
 	"time"
 )
@@ -89,8 +90,6 @@ func (wfs *WFS) Fsync(cancel <-chan struct{}, in *fuse.FsyncIn) (code fuse.Statu
 }
 
 func (wfs *WFS) doFlush(fh *FileHandle, uid, gid uint32) fuse.Status {
-	fh.Lock()
-	defer fh.Unlock()
 
 	// flush works at fh level
 	fileFullPath := fh.FullPath()
@@ -105,6 +104,9 @@ func (wfs *WFS) doFlush(fh *FileHandle, uid, gid uint32) fuse.Status {
 		}
 	}
 
+	fhActiveLock := fh.wfs.fhLockTable.AcquireLock("doFlush", fh.fh, util.ExclusiveLock)
+	defer fh.wfs.fhLockTable.ReleaseLock(fh.fh, fhActiveLock)
+
 	if !fh.dirtyMetadata {
 		return fuse.OK
 	}