[Linux-cachefs] [PATCH v10 4/4] xfs: use current->journal_info to avoid transaction reservation recursion

[Yafang Shao]

On Tue, Dec 8, 2020 at 10:42 AM Matthew Wilcox <willy at infradead.org> wrote:
>
> On Tue, Dec 08, 2020 at 10:15:43AM +0800, Yafang Shao wrote:
> > -     /*
> > -      * Given that we do not allow direct reclaim to call us, we should
> > -      * never be called in a recursive filesystem reclaim context.
> > -      */
> > -     if (WARN_ON_ONCE(current->flags & PF_MEMALLOC_NOFS))
> > -             goto redirty;
> > -
> >       /*
> >        * Is this page beyond the end of the file?
> >        *
> > diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
> > index 2371187b7615..28db93d0da97 100644
> > --- a/fs/xfs/xfs_aops.c
> > +++ b/fs/xfs/xfs_aops.c
> > @@ -568,6 +568,16 @@ xfs_vm_writepage(
> >  {
> >       struct xfs_writepage_ctx wpc = { };
> >
> > +     /*
> > +      * Given that we do not allow direct reclaim to call us, we should
> > +      * never be called while in a filesystem transaction.
> > +      */
> > +     if (xfs_trans_context_active()) {
> > +             redirty_page_for_writepage(wbc, page);
> > +             unlock_page(page);
> > +             return 0;
> > +     }
>
> Dave specifically asked for this one to WARN too.

I put the warn in xfs_trans_context_active(), pls. see the definition of it.
Is that okay ?

-- 
Thanks
Yafang