From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 21 Dec 2004 02:55:25 +0000 (GMT) From: Hugh Dickins Subject: Re: [RFC][PATCH 0/10] alternate 4-level page tables patches In-Reply-To: <1103590078.5121.15.camel@npiggin-nld.site> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Andi Kleen , Linus Torvalds , Linux Memory Management , Andrew Morton List-ID: On Tue, 21 Dec 2004, Nick Piggin wrote: > > Anyway, I'll continue to try to get more architecture support, Sorry for being dense: despite your earlier explanation, I've yet again lost track of why pud needs any flag day through the architectures - beyond the inclusion of some generic nopud.h, but different from the one you're rightly aiming for. Good as they are, imagine setting aside your nopmd.h mods as a cleanup for some other occasion. Then wouldn't a generic nopud.h something like #define pud_t pgd_t #define pud_alloc(mm, pgd, address) (pgd) #define pud_offset(pgd, start) (pgd) #define pud_none(pud) 0 #define pud_bad(pud) 0 #define pud_ERROR(pud) #define pud_clear(pud) #define PUD_SIZE PGDIR_SIZE #define PUD_MASK PGDIR_MASK get your kernel with common patch 6/10 compiling and working correctly on all architectures? with just a one-line mod to each architecture to include it? Your answer seems to be no, so I guess there's a place in the code you can point to, which shows up the nonsense of this suggestion: please humiliate me! Certainly x86_64 then needs to use other definitions to get its 4levels working. And it'd be highly advisable to convert i386 and some other common architectures (as you have already done) to use more typesafe declarations in which a pud_t is distinct from a pgd_t, so that people building mods to the common pagetable code cannot mix levels by mistake. But I don't see why the pagetable code in each arch subdirectory needs to have a pud level inserted all at once (whereas a flag day was needed for the pml4 patch, because mm->pgd got replaced by mm->pml4). Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org