From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 4 Jan 2005 11:58:13 -0800 (PST) From: Christoph Lameter Subject: Re: page fault scalability patch V14 [5/7]: x86_64 atomic pte operations In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andi Kleen Cc: Hugh Dickins , akpm@osdl.org, Nick Piggin , linux-mm@kvack.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org List-ID: On Tue, 4 Jan 2005, Andi Kleen wrote: > Christoph Lameter writes: > > I bet this has been never tested. I tested this back in October and it worked fine. Would you be able to test your proposed modifications and send me a patch? > > +#define pmd_test_and_populate(mm, pmd, pte) \ > > + (cmpxchg((int *)pmd, PMD_NONE, _PAGE_TABLE | __pa(pte)) == PMD_NONE) > > +#define pud_test_and_populate(mm, pud, pmd) \ > > + (cmpxchg((int *)pgd, PUD_NONE, _PAGE_TABLE | __pa(pmd)) == PUD_NONE) > > +#define pgd_test_and_populate(mm, pgd, pud) \ > > + (cmpxchg((int *)pgd, PGD_NONE, _PAGE_TABLE | __pa(pud)) == PGD_NONE) > > + > > Shouldn't this all be (long *)pmd ? page table entries on x86-64 are 64bit. > Also why do you cast at all? i think the macro should handle an arbitary > pointer. The macro checks for the size of the pointer and then generates the appropriate cmpxchg instruction. pgd_t is a struct which may be problematic for the cmpxchg macros. -- 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