On Fri, Apr 29, 2022 at 10:46 AM Yan, Zheng <ukernel@xxxxxxxxx> wrote:
>
> On Thu, Apr 28, 2022 at 11:42 PM Xiubo Li <xiubli@xxxxxxxxxx> wrote:
> >
> > For example if the Frwcb caps are being revoked, but only the Fr
> > caps is still being used then the kclient will skip releasing them
> > all. But in next turn if the Fr caps is ready to be released the
> > Fw caps maybe just being used again. So in corner case, such as
> > heavy load IOs, the revocation maybe stuck for a long time.
> >
> This does not make sense. If Frwcb are being revoked, writer can't get
> Fw again. Second, Frwcb are managed by single lock at mds side.
> Partial releasing caps does make lock state transition possible.
>
I mean, does not make lock state transition possible.
>
> > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
> > ---
> > fs/ceph/caps.c | 7 +++++++
> > 1 file changed, 7 insertions(+)
> >
> > diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
> > index 0c0c8f5ae3b3..7eb5238941fc 100644
> > --- a/fs/ceph/caps.c
> > +++ b/fs/ceph/caps.c
> > @@ -1947,6 +1947,13 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags,
> >
> > /* The ones we currently want to retain (may be adjusted below) */
> > retain = file_wanted | used | CEPH_CAP_PIN;
> > +
> > + /*
> > + * Do not retain the capabilities if they are under revoking
> > + * but not used, this could help speed up the revoking.
> > + */
> > + retain &= ~((revoking & retain) & ~used);
> > +
> > if (!mdsc->stopping && inode->i_nlink > 0) {
> > if (file_wanted) {
> > retain |= CEPH_CAP_ANY; /* be greedy */
> > --
> > 2.36.0.rc1
> >
