The block layer dropped the virtual merge feature (b8b3e16cfe6435d961f6aaebcfd52a1ff2a988c5). BIO_VMERGE_BOUNDARY definition is meaningless now (For IA64, BIO_VMERGE_BOUNDARY has been meaningless for a long time since IA64 disables the virtual merge feature). Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> --- arch/ia64/include/asm/io.h | 24 ------------------------ 1 files changed, 0 insertions(+), 24 deletions(-) diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h index 7f25750..0d9d16e 100644 --- a/arch/ia64/include/asm/io.h +++ b/arch/ia64/include/asm/io.h @@ -434,28 +434,4 @@ extern void memset_io(volatile void __iomem *s, int c, long n); # endif /* __KERNEL__ */ -/* - * Enabling BIO_VMERGE_BOUNDARY forces us to turn off I/O MMU bypassing. It is said that - * BIO-level virtual merging can give up to 4% performance boost (not verified for ia64). - * On the other hand, we know that I/O MMU bypassing gives ~8% performance improvement on - * SPECweb-like workloads on zx1-based machines. Thus, for now we favor I/O MMU bypassing - * over BIO-level virtual merging. - */ -extern unsigned long ia64_max_iommu_merge_mask; -#if 1 -#define BIO_VMERGE_BOUNDARY 0 -#else -/* - * It makes no sense at all to have this BIO_VMERGE_BOUNDARY macro here. Should be - * replaced by dma_merge_mask() or something of that sort. Note: the only way - * BIO_VMERGE_BOUNDARY is used is to mask off bits. Effectively, our definition gets - * expanded into: - * - * addr & ((ia64_max_iommu_merge_mask + 1) - 1) == (addr & ia64_max_iommu_vmerge_mask) - * - * which is precisely what we want. - */ -#define BIO_VMERGE_BOUNDARY (ia64_max_iommu_merge_mask + 1) -#endif - #endif /* _ASM_IA64_IO_H */ -- 1.5.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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