Messages in this thread Patch in this message | | | Date | Fri, 8 Sep 2006 13:26:48 +0100 | From | Andy Whitcroft <> | Subject | [PATCH 4/5] linear reclaim add pfn_valid_within for zone holes |
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linear reclaim add pfn_valid_within for zone holes
Generally we work under the assumption that memory the mem_map array is contigious and valid out to MAX_ORDER blocks. When this is not true we much check each and every reference we make from a pfn. Add a pfn_valid_within() which should be used when checking pages within a block when we have already checked the validility of the block normally. This can then be optimised away when we have holes.
Added in: V1
Signed-off-by: Andy Whitcroft <apw@shadowen.org> --- diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 3d31354..8c09638 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -680,6 +680,18 @@ #endif void memory_present(int nid, unsigned long start, unsigned long end); unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long); +/* + * If we have holes within zones (smaller than MAX_ORDER) then we need + * to check pfn validility within MAX_ORDER blocks. pfn_valid_within + * should be used in this case; we optimise this away when we have + * no holes. + */ +#ifdef CONFIG_HOLES_IN_ZONE +#define pfn_valid_within(pfn) pfn_valid(pfn) +#else +#define pfn_valid_within(pfn) (1) +#endif + #endif /* !__ASSEMBLY__ */ #endif /* __KERNEL__ */ #endif /* _LINUX_MMZONE_H */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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