diff options
-rw-r--r-- | include/asm-generic/page.h | 38 |
1 files changed, 4 insertions, 34 deletions
diff --git a/include/asm-generic/page.h b/include/asm-generic/page.h index b55052ce2330..a96b5d986b6e 100644 --- a/include/asm-generic/page.h +++ b/include/asm-generic/page.h | |||
@@ -4,51 +4,21 @@ | |||
4 | #ifdef __KERNEL__ | 4 | #ifdef __KERNEL__ |
5 | #ifndef __ASSEMBLY__ | 5 | #ifndef __ASSEMBLY__ |
6 | 6 | ||
7 | #include <linux/log2.h> | 7 | #include <linux/compiler.h> |
8 | 8 | ||
9 | /* | 9 | /* Pure 2^n version of get_order */ |
10 | * non-const pure 2^n version of get_order | 10 | static __inline__ __attribute_const__ int get_order(unsigned long size) |
11 | * - the arch may override these in asm/bitops.h if they can be implemented | ||
12 | * more efficiently than using the arch log2 routines | ||
13 | * - we use the non-const log2() instead if the arch has defined one suitable | ||
14 | */ | ||
15 | #ifndef ARCH_HAS_GET_ORDER | ||
16 | static inline __attribute__((const)) | ||
17 | int __get_order(unsigned long size, int page_shift) | ||
18 | { | 11 | { |
19 | #if BITS_PER_LONG == 32 && defined(ARCH_HAS_ILOG2_U32) | ||
20 | int order = __ilog2_u32(size) - page_shift; | ||
21 | return order >= 0 ? order : 0; | ||
22 | #elif BITS_PER_LONG == 64 && defined(ARCH_HAS_ILOG2_U64) | ||
23 | int order = __ilog2_u64(size) - page_shift; | ||
24 | return order >= 0 ? order : 0; | ||
25 | #else | ||
26 | int order; | 12 | int order; |
27 | 13 | ||
28 | size = (size - 1) >> (page_shift - 1); | 14 | size = (size - 1) >> (PAGE_SHIFT - 1); |
29 | order = -1; | 15 | order = -1; |
30 | do { | 16 | do { |
31 | size >>= 1; | 17 | size >>= 1; |
32 | order++; | 18 | order++; |
33 | } while (size); | 19 | } while (size); |
34 | return order; | 20 | return order; |
35 | #endif | ||
36 | } | 21 | } |
37 | #endif | ||
38 | |||
39 | /** | ||
40 | * get_order - calculate log2(pages) to hold a block of the specified size | ||
41 | * @n - size | ||
42 | * | ||
43 | * calculate allocation order based on the current page size | ||
44 | * - this can be used to initialise global variables from constant data | ||
45 | */ | ||
46 | #define get_order(n) \ | ||
47 | ( \ | ||
48 | __builtin_constant_p(n) ? \ | ||
49 | ((n < (1UL << PAGE_SHIFT)) ? 0 : ilog2(n) - PAGE_SHIFT) : \ | ||
50 | __get_order(n, PAGE_SHIFT) \ | ||
51 | ) | ||
52 | 22 | ||
53 | #endif /* __ASSEMBLY__ */ | 23 | #endif /* __ASSEMBLY__ */ |
54 | #endif /* __KERNEL__ */ | 24 | #endif /* __KERNEL__ */ |