When running 64k pages it became apparent that it was possible that the kernel could create more TLB pressure in certain circumstances when compared to the 4k page kernel. This is due to the fact that large portions of the 4k kernel can be mapped with 2M blocks. While the larger block size for 64k pages is 512M, it frequently won't be used for assorted reasons.
ARMv8 has a contiguous PTE bit that allows the TLBs to map a range larger than a single PTE if the range is physically contiguous. So its a good idea to use this where appropriate for the kernel mapping. This patch adds the definitions for the contiguous bit, updates the kernel page range dump to understand them (and block translations), and updates the code in mmu.c to use the contiguous bit where appropriate for the kernel linear mapping. Jeremy Linton (7): arm64: Add contiguous page flag shifts and constants arm64: Shorten lines which exceed 80 characters arm64: PTE/PMD contiguous bit definition arm64: Macros to check/set/unset the contiguous bit arm64: Default kernel pages should be contiguous arm64: Make the kernel page dump utility aware of the CONT bit arm64: Mark kernel page ranges contiguous arch/arm64/include/asm/page.h | 8 +++- arch/arm64/include/asm/pgtable-hwdef.h | 25 ++++++++---- arch/arm64/include/asm/pgtable.h | 13 +++++++ arch/arm64/mm/dump.c | 18 ++++++++- arch/arm64/mm/mmu.c | 70 ++++++++++++++++++++++++++++++---- 5 files changed, 116 insertions(+), 18 deletions(-) -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
