On 07/30/24 at 11:24am, Hailong Liu wrote: > On Mon, 29. Jul 09:48, Baoquan He wrote: > [...] > > Hi Hailong, > > > > Please feel free to collect them to post formal patch, maybe two > > patches, one is to allow non-nofail to fallback to order-0 in > > vm_area_alloc_pages(), the other is passing out the fallbacked > > page_order to vmap_pages_range() if it's OK. > Sorry for late response. I personally prefer to revert part of > the problematic patch. There are several reasons: > - Save memory usage if high order allocation failed. > - If nofail and fallback to order0 in vmalloc huge allocation, > actually the allocation is alighed with PMD_SIZE or not PAGE_SHIFT. It's OK, maybe you can post patch to show what it looks like, we can review and discuss there. > > You might be concerned about performance issues. But IMO, > - If we fallback to order0, we can make use of bulk allocator. > - Maybe we can remove VM_ALLOW_HUGE_VMAP in kvmalloc. > > I am not sure if I have misunderstood anything. If I have, please > let me know. > > > > Thanks > > Baoquan > > > > > > -- > help you, help me, > Hailong. >
