mtwriteavar() for final inode in namex

cc5b59ab · Nickolai Zeldovich · 1ce14b62 · cc5b59ab · cc5b59ab
--- a/kernel/fs.cc
+++ b/kernel/fs.cc
@@ -775,7 +775,13 @@ namex(inode *cwd, const char *path, int nameiparent, char *name)
  if(r == -1 || nameiparent)
    return 0;

-  mtreadavar("inode:%x.%x", ip->dev, ip->inum);
+  // XXX write is necessary because of idup.  not logically required,
+  // so we should replace this with mtreadavar() eventually, perhaps
+  // once we implement sloppy counters for long-term inode refs.
+
+  // mtreadavar("inode:%x.%x", ip->dev, ip->inum);
+  mtwriteavar("inode:%x.%x", ip->dev, ip->inum);
+
  idup(ip);
  return ip;
 }

--- a/kernel/sysfile.cc
+++ b/kernel/sysfile.cc
@@ -296,6 +296,10 @@ sys_openat(int dirfd, const char *path, int omode)
  if(omode & O_CREATE){
    if((ip = create(cwd, path, T_FILE, 0, 0)) == 0)
      return -1;
+
+    // XXX necessary because the mtwriteavar() to the same abstract variable
+    // does not propagate to our scope, since create() has its own inner scope.
+    mtwriteavar("inode:%x.%x", ip->dev, ip->inum);
  } else {
 retry:
    if((ip = namei(cwd, path)) == 0)