[PATCH 2/7] Add various hugetlb page table fix
From: carson bill <hidden>
Date: 2012-02-07 15:41:29
2012/2/7, Catalin Marinas [off-list ref]:
On Tue, Feb 07, 2012 at 02:46:50PM +0000, carson bill wrote:quoted
2012/2/7, Catalin Marinas [off-list ref]:quoted
But if you avoid setting L_PTE_HPAGE_*, than we don't need the masking for pte_pfn. In which case, we don't need to differentiate between a normal and a huge pte in pte_pfn(), so no need for L_PTE_HUGEPAGE. The set_huge_pte_at() function is only called with a huge pte, so it doesn't need to check the L_PTE_HUGEPAGE bit either.I understood what you mean now, and the original design is almost like you said. But the consequences of eliminating L_PTE_HUGEPAGE as well as L_PTE_HPAGE_* only leave us with huge page size fixed at build time, I mean boot time huge page size configuration feature like X86 will NOT be feasible anymore!Yes it will :). Just store the page size in some variable that you check at run-time. We won't support mixed huge page sizes though.
Got it:) Please review the other parts of patch, let me know if any question arises.
-- Catalin