On Thu, 25 Mar 2021 at 00:09, Minchan Kim <[email protected]> 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 successful allocations > * 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/alloc_pages_[success|fail] > /sys/kernel/mm/cma/SENSOR/alloc_pages_[success|fail] > /sys/kernel/mm/cma/BLUETOOTH/alloc_pages_[success|fail] > > The cma_stat was intentionally allocated by dynamic allocation > to harmonize with kobject lifetime management. > https://lore.kernel.org/linux-mm/[email protected]/ > > Tested-by: Dmitry Osipenko <[email protected]> > Reviewed-by: Dmitry Osipenko <[email protected]> > Reviewed-by: Greg Kroah-Hartman <[email protected]> > Reviewed-by: John Hubbard <[email protected]> > Link: > https://lore.kernel.org/linux-mm/[email protected]/ > Addresses-Coverity: ("Dereference after null check") > Signed-off-by: Colin Ian King <[email protected]> > Signed-off-by: Minchan Kim <[email protected]>
Tested-by: Anders Roxell <[email protected]>
