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charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri 23-08-24 18:42:47, Uladzislau Rezki wrote: [...] > @@ -3666,7 +3655,16 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, > set_vm_area_page_order(area, page_shift - PAGE_SHIFT); > page_order = vm_area_page_order(area); > > - area->nr_pages = vm_area_alloc_pages(gfp_mask | __GFP_NOWARN, > + /* > + * Higher order nofail allocations are really expensive and > + * potentially dangerous (pre-mature OOM, disruptive reclaim > + * and compaction etc. > + * > + * Please note, the __vmalloc_node_range_noprof() falls-back > + * to order-0 pages if high-order attempt has been unsuccessful. > + */ > + area->nr_pages = vm_area_alloc_pages(page_order ? > + gfp_mask &= ~__GFP_NOFAIL : gfp_mask | __GFP_NOWARN, > node, page_order, nr_small_pages, area->pages); > > atomic_long_add(area->nr_pages, &nr_vmalloc_pages); > > > Is that aligned with your wish? I am not a great fan of modifying gfp_mask inside the ternary operator like that. It makes the code harder to read. Is there any actual reason to simply drop GFP_NOFAIL unconditionally and rely do the NOFAIL handling for all orders at the same place? Not that I care about this much TBH. It is an improvement to drop all the NOFAIL specifics from vm_area_alloc_pages. -- Michal Hocko SUSE Labs