On Thu, 2022-02-24 at 09:14 -0500, Benjamin Coddington wrote:
> On 23 Feb 2022, at 16:12, trondmy@xxxxxxxxxx wrote:
>
> > From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> >
> > Enable tracing of lookup revalidation failures.
> >
> > Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> > ---
> > fs/nfs/dir.c | 17 +++++------------
> > 1 file changed, 5 insertions(+), 12 deletions(-)
> >
> > diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> > index ebddc736eac2..1aa55cac9d9a 100644
> > --- a/fs/nfs/dir.c
> > +++ b/fs/nfs/dir.c
> > @@ -1474,9 +1474,7 @@ nfs_lookup_revalidate_done(struct inode *dir,
> > struct dentry *dentry,
> > {
> > switch (error) {
> > case 1:
> > - dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is valid\n",
> > - __func__, dentry);
> > - return 1;
> > + break;
> > case 0:
> > /*
> > * We can't d_drop the root of a disconnected tree:
> > @@ -1485,13 +1483,10 @@ nfs_lookup_revalidate_done(struct inode
> > *dir,
> > struct dentry *dentry,
> > * inodes on unmount and further oopses.
> > */
> > if (inode && IS_ROOT(dentry))
> > - return 1;
> > - dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is invalid\n",
> > - __func__, dentry);
> > - return 0;
> > + error = 1;
> > + break;
> > }
> > - dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) lookup returned error
> > %d\n",
> > - __func__, dentry, error);
> > + trace_nfs_lookup_revalidate_exit(dir, dentry, 0, error);
>
>
> There's a path through nfs4_lookup_revalidate that will now only
> produce
> this exit tracepoint. Does it need the _enter tracepoint added?
You're thinking about the nfs_lookup_revalidate_delegated() path? The
_enter() tracepoint doesn't provide any useful information that isn't
already provided by the _exit(), AFAICS.
--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx
