2020년 7월 17일 (금) 오후 5:32, David Laight <[email protected]>님이 작성: > > From: [email protected] > > Sent: 15 July 2020 06:05 > > From: Joonsoo Kim <[email protected]> > > > > Currently, preventing cma area in page allocation is implemented by using > > current_gfp_context(). However, there are two problems of this > > implementation. > ... > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index 6416d08..cd53894 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > ... > > @@ -3693,6 +3691,16 @@ alloc_flags_nofragment(struct zone *zone, gfp_t > > gfp_mask) > > return alloc_flags; > > } > > > > +static inline void current_alloc_flags(gfp_t gfp_mask, > > + unsigned int *alloc_flags) > > +{ > > + unsigned int pflags = READ_ONCE(current->flags); > > + > > + if (!(pflags & PF_MEMALLOC_NOCMA) && > > + gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE) > > + *alloc_flags |= ALLOC_CMA; > > +} > > + > > I'd guess this would be easier to understand and probably generate > better code if renamed and used as: > alloc_flags |= can_alloc_cma(gpf_mask); > > Given it is a 'static inline' the compiler might end up > generating the same code. > If you needed to clear a flag doing: > alloc_flags = current_alloc_flags(gpf_mask, alloc_flags); > is much better for non-inlined function.
Vlastimil suggested this way and I have agreed with that. Anyway, thanks for the suggestion. Thanks.
