Re: [PATCH v3] mm: cma: support sysfs

[Minchan Kim]

On Wed, Feb 10, 2021 at 12:05:48AM -0800, John Hubbard wrote:
> On 2/9/21 11:55 PM, Minchan Kim wrote:
> > Since CMA is getting used more widely, it's more important to
> > keep monitoring CMA statistics for system health since it's
> > directly related to user experience.
> > 
> > This patch introduces sysfs statistics for CMA, in order to provide
> > some basic monitoring of the CMA allocator.
> > 
> >   * the number of CMA page allocation attempts
> >   * the number of CMA page allocation failures
> > 
> > These two values allow the user to calcuate the allocation
> > failure rate for each CMA area.
> > 
> > e.g.)
> >    /sys/kernel/mm/cma/WIFI/cma_alloc_pages_[attempts|fails]
> >    /sys/kernel/mm/cma/SENSOR/cma_alloc_pages_[attempts|fails]
> >    /sys/kernel/mm/cma/BLUETOOTH/cma_alloc_pages_[attempts|fails]
> > 
> > Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
> > ---
> 
> Looks good.
> 
> Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>

Thanks for reviewing, John and Greg!