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>