.

wcfs/client/wcfs.cpp

@@ -183,6 +183,7 @@
 // (*) see "Wcfs locking organization" in wcfs.go
 // (%) see related comment in Conn.__pin1 for details.
 
+
 // Handling of fork
 //
 // When a process calls fork, OS copies its memory and creates child process

wcfs/internal/wcfs_test.pyx

@@ -160,7 +160,7 @@ cdef extern from "<fcntl.h>" nogil:
     int posix_fadvise(int fd, off_t offset, off_t len, int advice);
     enum: POSIX_FADV_DONTNEED
 
-# fadvise_dontneed teels the kernel that file<fd>[offset +len) is not needed.
+# fadvise_dontneed tells the kernel that file<fd>[offset +len) is not needed.
 #
 # see fadvise(2) for details.
 def fadvise_dontneed(int fd, off_t offset, off_t len):

wcfs/wcfs.go

@@ -602,7 +602,8 @@ type BigFileDir struct {
 
 	// δ tail of tracked BTree nodes of all BigFiles + -> which file
 	// (used only for head/, not revX/)
-	δFmu   sync.RWMutex		// zheadMu.W  |  zheadMu.R + δFmu.X	XXX kill δFmu
+	// XXX read/write access protected by zheadMu
+//	δFmu   sync.RWMutex		// zheadMu.W  |  zheadMu.R + δFmu.X	XXX kill δFmu
 	δFtail *zdata.ΔFtail
 }
 
@@ -1533,10 +1534,10 @@ func (f *BigFile) readPinWatchers(ctx context.Context, blk int64, treepath []btr
 	// see "3) for */head/data the following invariant is maintained..."
 	bfdir := f.head.bfdir
 	δFtail := bfdir.δFtail
-	bfdir.δFmu.Lock()		// XXX locking correct? XXX -> better push down?
+//	bfdir.δFmu.Lock()		// XXX locking correct? XXX -> better push down?
 	δFtail.Track(f.zfile, blk, treepath, blkcov, zblk)	// XXX pass in zblk.rev here?
 	f.accessed.Add(blk)
-	bfdir.δFmu.Unlock()
+//	bfdir.δFmu.Unlock()
 
 	// make sure that file[blk] on clients side stays as of @w.at state.
 
@@ -1634,7 +1635,7 @@ func (wlink *WatchLink) setupWatch(ctx context.Context, foid zodb.Oid, at zodb.T
 	defer head.zheadMu.RUnlock()
 	headAt := head.zconn.At()
 
-	// XXX δFtail locking? (or ForgetPast is called only with zheadMu.W ?)
+//	// XXX δFtail locking? (or ForgetPast is called only with zheadMu.W ? - yes)
 	if at != zodb.InvalidTid && at < bfdir.δFtail.Tail() {
 		return fmt.Errorf("too far away back from head/at (@%s); δt = %s",
 			headAt, headAt.Time().Sub(at.Time().Time))
@@ -2264,9 +2265,9 @@ func (head *Head) bigopen(ctx context.Context, oid zodb.Oid) (_ *BigFile, err er
 	// only head/ needs δFtail, f.δtail and watches.
 	if head.rev == 0 {
 		// see "3) for */head/data the following invariant is maintained..."
-		head.bfdir.δFmu.Lock()	// XXX locking ok?
+//		head.bfdir.δFmu.Lock()	// XXX locking ok?
 		head.bfdir.δFtail.Track(f.zfile, -1, sizePath, blkCov, nil)
-		head.bfdir.δFmu.Unlock()
+//		head.bfdir.δFmu.Unlock()
 
 		// FIXME: scan zfile.blktab - so that we can detect all btree changes
 		// see  "XXX building δFtail lazily ..." in notes.txt