[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <45B6CE8C.8010807@yahoo.com.au>
Date: Wed, 24 Jan 2007 14:12:12 +1100
From: Nick Piggin <nickpiggin@...oo.com.au>
To: Paul Davies <pauld@....unsw.edu.au>
CC: linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/1] Page Table cleanup patch
Paul Davies wrote:
> This patch is a proposed cleanup of the current page table organisation.
> Such a cleanup would be a logical first step towards introducing at least
> a partial clean page table interface, geared towards providing enhanced
> virtualization oportunities for x86. It is also a common sense cleanup
> in its own right.
>
> * Creates mlpt.c to hold the page table implementation currently held
> in memory.c.
> * Adjust Makefile
> * Move implementation dependent page table code out of
> include/linux/mm.h into include/linux/mlpt-mm.h
> * Move implementation dependent page table code out of
> include/asm-generic/pgtable.h to include/asm-generic/pgtable-mlpt.h
>
> mlpt stands from multi level page table.
Hi Paul,
I'm not sure that I see the point of this patch alone, as there is still
all the mlpt implementation details in all the page table walkers. Or
did you have a scheme to change implementations somehow just using the
p*d_addr_next?
> -#ifndef __PAGETABLE_PUD_FOLDED
> -/*
> - * Allocate page upper directory.
> - * We've already handled the fast-path in-line.
> - */
> -int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
> -{
> - pud_t *new = pud_alloc_one(mm, address);
> - if (!new)
> - return -ENOMEM;
> -
> - spin_lock(&mm->page_table_lock);
> - if (pgd_present(*pgd)) /* Another has populated it */
> - pud_free(new);
> - else
> - pgd_populate(mm, pgd, new);
> - spin_unlock(&mm->page_table_lock);
> - return 0;
> -}
> -#else
> -/* Workaround for gcc 2.96 */
> -int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
> -{
> - return 0;
> -}
> -#endif /* __PAGETABLE_PUD_FOLDED */
...
> -/* Workaround for gcc 2.96 */
> -int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
> -{
> - return 0;
> -}
> -#endif /* __PAGETABLE_PMD_FOLDED */
Hmm, we're gcc-3.2 minimum now -- let's get rid of that crud?
--
SUSE Labs, Novell Inc.
Send instant messages to your online friends http://au.messenger.yahoo.com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists