Re: [PATCH 04/13] lightnvm: pblk: Rollback in gc read

Hans Holmberg
2019-03-04T12:42:49Z

On Mon, Mar 4, 2019 at 1:39 PM Igor Konopko <igor.j.konopko@intel.com> wrote:
>
>
>
> On 04.03.2019 09:44, Hans Holmberg wrote:
> > Did you ever see this in the wild?
> > The only time pblk_gc_line returns an error is if
> > kmalloc(sizeof(struct pblk_line_ws), GFP_KERNEL); fails, and then
> > we're in real trouble :)
>
> I never saw this in real life, but still probably good to have a
> "proper" handling - since we already have "some" handling.

Yes!

>
> >
> > Reviewed-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
> >
> > On Mon, Mar 4, 2019 at 8:38 AM Javier González <javier@javigon.com> wrote:
> >>
> >>> On 27 Feb 2019, at 18.14, Igor Konopko <igor.j.konopko@intel.com> wrote:
> >>>
> >>> Currently in case of error returned by pblk_gc_line
> >>> to pblk_gc_read we leave current line unassigned
> >>> from all the lists. This patch fixes that issue.
> >>>
> >>> Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
> >>> ---
> >>> drivers/lightnvm/pblk-gc.c | 7 ++++++-
> >>> 1 file changed, 6 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/lightnvm/pblk-gc.c b/drivers/lightnvm/pblk-gc.c
> >>> index 511ed0d5333c..533da6ea3e15 100644
> >>> --- a/drivers/lightnvm/pblk-gc.c
> >>> +++ b/drivers/lightnvm/pblk-gc.c
> >>> @@ -361,8 +361,13 @@ static int pblk_gc_read(struct pblk *pblk)
> >>>
> >>> pblk_gc_kick(pblk);
> >>>
> >>> - if (pblk_gc_line(pblk, line))
> >>> + if (pblk_gc_line(pblk, line)) {
> >>> pblk_err(pblk, "failed to GC line %d\n", line->id);
> >>> + /* rollback */
> >>> + spin_lock(&gc->r_lock);
> >>> + list_add_tail(&line->list, &gc->r_list);
> >>> + spin_unlock(&gc->r_lock);
> >>> + }
> >>>
> >>> return 0;
> >>> }
> >>> --
> >>> 2.17.1
> >>
> >> Looks good to me.
> >>
> >> Reviewed-by: Javier González <javier@javigon.com>