Re: [PATCH 1/1] use documented cmpxchg api
From: Pranith Kumar
Date: Fri Jun 06 2014 - 10:27:31 EST
On 06/06/2014 06:55 AM, Peter Hurley wrote:
>
> This won't work either, and should generate a compile or link error
> on CONFIG_X86_32.
>
> The auto-sizing done by __cmpxchg() does not substitute the cmpxchg8b
> instruction for the cmpxchg instruction. __X86_CASE_Q is defined as -1 for
> CONFIG_X86_32 so the 8-byte size variant is dead-code, and calls
> __cmpxchg_wrong_size() instead.
>
>
Fixed with the following v3:
use the documented cmpxchg64 instead of __cmpxchg64.
This kills the last user of said API in drivers code.
Signed-off-by: Pranith Kumar <bobby.prani@xxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 6bb3277..270113f 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -293,7 +293,7 @@ static inline u64 dma_pte_addr(struct dma_pte *pte)
return pte->val & VTD_PAGE_MASK;
#else
/* Must have a full atomic 64-bit read */
- return __cmpxchg64(&pte->val, 0ULL, 0ULL) & VTD_PAGE_MASK;
+ return cmpxchg64(&pte->val, 0ULL, 0ULL) & VTD_PAGE_MASK;
#endif
}
-- 1.7.9.5
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