On Thu, Jan 19, 2023 at 1:24 PM Trond Myklebust <trondmy@xxxxxxxxxxxxxxx> wrote:
>
>
>
> > On Jan 19, 2023, at 12:50, Olga Kornievskaia <olga.kornievskaia@xxxxxxxxx> wrote:
> >
> > If the call to GETDEVICEINFO fails, the client fallback to doing IO
> > to MDS but on every new IO call, the client tries to get the device
> > again. Instead, mark the layout as unavailable as well. This way
> > the client will re-try after a timeout period.
> >
> > Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
> > ---
> > fs/nfs/filelayout/filelayout.c | 1 +
> > fs/nfs/pnfs.c | 7 +++++++
> > fs/nfs/pnfs.h | 2 ++
> > 3 files changed, 10 insertions(+)
> >
> > diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
> > index 4974cd18ca46..13df85457cf5 100644
> > --- a/fs/nfs/filelayout/filelayout.c
> > +++ b/fs/nfs/filelayout/filelayout.c
> > @@ -862,6 +862,7 @@ fl_pnfs_update_layout(struct inode *ino,
> >
> > status = filelayout_check_deviceid(lo, fl, gfp_flags);
> > if (status) {
> > + pnfs_mark_layout_unavailable(lo, iomode);
> > pnfs_put_lseg(lseg);
> > lseg = NULL;
> > }
> > diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
> > index a5db5158c634..bac15dcf99bb 100644
> > --- a/fs/nfs/pnfs.c
> > +++ b/fs/nfs/pnfs.c
> > @@ -491,6 +491,13 @@ pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
> > refcount_inc(&lo->plh_refcount);
> > }
> >
> > +void
> > +pnfs_mark_layout_unavailable(struct pnfs_layout_hdr *lo, enum pnfs_iomode fail_bit)
> > +{
> > + pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(fail_bit));
>
> I suggest rather using pnfs_layout_io_set_failed() so that we also evict the layout segment that references this unrecognised deviceid. In fact, there is already an exported function pnfs_set_lo_fail() (which could definitely do with a better name!) that does this.
I'm not opposed to this approach. In the proposed patch, I treated it
as the layout being still valid but unavailable. My question is: I
think we need to return the layout before doing this, correct? Should
I be making changes to export something like
pnfs_set_plh_return_info() or would adding a new function to pnfs.c
that does pnfs_set_lo_fail and returns the layout?
something like
+void pnfs_invalidate_return_layout(struct pnfs_layout_segment *lseg)
+{
+ pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
+ pnfs_set_plh_return_info(lseg->pls_layout, lseg->pls_range.iomode, 0);
+}
+EXPORT_SYMBOL_GPL(pnfs_invalidate_return_layout);
status = filelayout_check_deviceid(lo, fl, gfp_flags);
if (status) {
+ pnfs_invalidate_return_layout(lseg);
pnfs_put_lseg(lseg);
lseg = NULL;
>
> > +}
> > +EXPORT_SYMBOL_GPL(pnfs_mark_layout_unavailable);
> > +
> > static void
> > pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
> > {
> > diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
> > index e3e6a41f19de..9f47bd883fc3 100644
> > --- a/fs/nfs/pnfs.h
> > +++ b/fs/nfs/pnfs.h
> > @@ -343,6 +343,8 @@ void pnfs_error_mark_layout_for_return(struct inode *inode,
> > void pnfs_layout_return_unused_byclid(struct nfs_client *clp,
> > enum pnfs_iomode iomode);
> >
> > +void pnfs_mark_layout_unavailable(struct pnfs_layout_hdr *lo,
> > + enum pnfs_iomode iomode);
> > /* nfs4_deviceid_flags */
> > enum {
> > NFS_DEVICEID_INVALID = 0, /* set when MDS clientid recalled */
> > --
> > 2.31.1
> >
>
> _________________________________
> Trond Myklebust
> Linux NFS client maintainer, Hammerspace
> trond.myklebust@xxxxxxxxxxxxxxx
>
