Re: [PATCH 07/13] lightnvm: pblk: Cleanly fail when there is not enough memory

Hans Holmberg
2019-03-04T09:24:20Z

Hi Igor,

I think you need to motivate (and document) why each of the new flags
are needed.

Thanks,
Hans

On Mon, Mar 4, 2019 at 8:53 AM Javier González <javier@javigon.com> wrote:
>
> > On 27 Feb 2019, at 18.14, Igor Konopko <igor.j.konopko@intel.com> wrote:
> >
> > L2P table can be huge in many cases, since
> > it typically requires 1GB of DRAM for 1TB
> > of drive. When there is not enough memory
> > available, OOM killer turns on and kills
> > random processes, which can be very annoying
> > for users. This patch changes the flag for
> > L2P table allocation on order to handle this
> > situation in more user friendly way
> >
> > Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
> > ---
> > drivers/lightnvm/pblk-init.c | 9 +++++++--
> > 1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
> > index 8b643d0bffae..e553105b7ba1 100644
> > --- a/drivers/lightnvm/pblk-init.c
> > +++ b/drivers/lightnvm/pblk-init.c
> > @@ -164,9 +164,14 @@ static int pblk_l2p_init(struct pblk *pblk, bool factory_init)
> > int ret = 0;
> >
> > map_size = pblk_trans_map_size(pblk);
> > - pblk->trans_map = vmalloc(map_size);
> > - if (!pblk->trans_map)
> > + pblk->trans_map = __vmalloc(map_size, GFP_KERNEL | __GFP_NOWARN
> > + | __GFP_RETRY_MAYFAIL | __GFP_HIGHMEM,
> > + PAGE_KERNEL);
> > + if (!pblk->trans_map) {
> > + pblk_err(pblk, "failed to allocate L2P (need %ld of memory)\n",
> > + map_size);
> > return -ENOMEM;
> > + }
> >
> > pblk_ppa_set_empty(&ppa);
> >
> > --
> > 2.17.1
>
> Is there any extra consideration we should take when enabling high
> memory for the L2P table? If not, looks good to me.
>
> Reviewed-by: Javier González <javier@javigon.com>