On Mon, 16 May 2022 10:04:54 +0200 Nico Boehr <nrb@xxxxxxxxxxxxx> wrote: > On Thu, 2022-04-14 at 10:02 +0200, Claudio Imbrenda wrote: > > Refactor s390_reset_acc so that it can be reused in upcoming patches. > > > > We don't want to hold all the locks used in a walk_page_range for too > > long, and the destroy page UVC does take some time to complete. > > Therefore we quickly gather the pages to destroy, and then destroy > > them > > without holding all the locks. > > > > The new refactored function optionally allows to return early without > > completing if a fatal signal is pending (and return and appropriate > > error code). Two wrappers are provided to call the new function. > > > > Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> > > Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx> > > Reviewed-by: Nico Boehr <nrb@xxxxxxxxxxxxx> > > But see below with one naming suggestion you might want to take into > account. > > [...] > > diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c > > index e8904cb9dc38..a3a1f90f6ec1 100644 > > --- a/arch/s390/mm/gmap.c > > +++ b/arch/s390/mm/gmap.c > > @@ -2676,44 +2676,81 @@ void s390_reset_cmma(struct mm_struct *mm) > > } > > EXPORT_SYMBOL_GPL(s390_reset_cmma); > > > > -/* > > - * make inaccessible pages accessible again > > - */ > > -static int __s390_reset_acc(pte_t *ptep, unsigned long addr, > > - unsigned long next, struct mm_walk *walk) > > +#define DESTROY_LOOP_THRESHOLD 32 > > maybe GATHER_NUM_PAGE_REFS_TO_TAKE? what about GATHER_GET_PAGES ?