On Wed, Feb 17, 2021 at 12:57:25PM -0800, John Hubbard wrote:
> On 2/17/21 9:00 AM, Minchan Kim wrote:
> > Since CMA is used more widely, it's worth to have CMA
> > allocation statistics into vmstat. With it, we could
> > know how agressively system uses cma allocation and
> > how often it fails.
> >
> > Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
> > ---
> > include/linux/vm_event_item.h | 3 +++
> > mm/cma.c | 12 +++++++++---
> > mm/vmstat.c | 4 ++++
> > 3 files changed, 16 insertions(+), 3 deletions(-)
> >
> > diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
> > index 18e75974d4e3..0c567014ce82 100644
> > --- a/include/linux/vm_event_item.h
> > +++ b/include/linux/vm_event_item.h
> > @@ -70,6 +70,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
> > #endif
> > #ifdef CONFIG_HUGETLB_PAGE
> > HTLB_BUDDY_PGALLOC, HTLB_BUDDY_PGALLOC_FAIL,
> > +#endif
> > +#ifdef CONFIG_CMA
> > + CMA_ALLOC, CMA_ALLOC_FAIL,
>
> This seems wrong: here it's called "alloc", but in the output it's
> called "alloc success", and in the implementation it's clearly
> "alloc attempt" that is being counted.
Argh, I wanted to introduce CMA_ALLOC, not ALLOC_ATTEMPTS.
Let me fix.
>
> Once these are all made consistent, then the bug should naturally
> go away as part of that.
>
> nit: I think the multiple items per line is a weak idea at best, even
> though it's used here already. Each item is important and needs to be
> visually compared to it's output item later. So one per line might
> have helped avoid mismatches, and I think we should change to that to
> encourage that trend.
No problem.
Thanks for the review, John.
