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

[Greg KH]

On Tue, Feb 09, 2021 at 11:55:09PM -0800, 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>

For the sysfs stuff:

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>