2020년 7월 16일 (목) 오후 4:45, Vlastimil Babka <vbabka@xxxxxxx>님이 작성: > > On 7/16/20 9:27 AM, Joonsoo Kim wrote: > > 2020년 7월 15일 (수) 오후 5:24, Vlastimil Babka <vbabka@xxxxxxx>님이 작성: > >> > /* > >> > * get_page_from_freelist goes through the zonelist trying to allocate > >> > * a page. > >> > @@ -3706,6 +3714,8 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, > >> > struct pglist_data *last_pgdat_dirty_limit = NULL; > >> > bool no_fallback; > >> > > >> > + current_alloc_flags(gfp_mask, &alloc_flags); > >> > >> I don't see why to move the test here? It will still be executed in the > >> fastpath, if that's what you wanted to avoid. > > > > I want to execute it on the fastpath, too. Reason that I moved it here > > is that alloc_flags could be reset on slowpath. See the code where > > __gfp_pfmemalloc_flags() is on. This is the only place that I can apply > > this option to all the allocation paths at once. > > But get_page_from_freelist() might be called multiple times in the slowpath, and > also anyone looking for gfp and alloc flags setup will likely not examine this > function. I don't see a problem in having it in two places that already deal > with alloc_flags setup, as it is now. I agree that anyone looking alloc flags will miss that function easily. Okay. I will place it on its original place, although we now need to add one more place. *Three places* are gfp_to_alloc_flags(), prepare_alloc_pages() and __gfp_pfmemalloc_flags(). Thanks.
