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8c4127c5 MD |
1 | #ifndef _UST_ALIGN_H |
2 | #define _UST_ALIGN_H | |
3 | ||
4 | /* | |
4318ae1b | 5 | * lttng/align.h |
8c4127c5 MD |
6 | * |
7 | * (C) Copyright 2010-2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
8 | * | |
e92f3e28 MD |
9 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
10 | * of this software and associated documentation files (the "Software"), to deal | |
11 | * in the Software without restriction, including without limitation the rights | |
12 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
13 | * copies of the Software, and to permit persons to whom the Software is | |
14 | * furnished to do so, subject to the following conditions: | |
a60d70e6 | 15 | * |
e92f3e28 MD |
16 | * The above copyright notice and this permission notice shall be included in |
17 | * all copies or substantial portions of the Software. | |
d2428e87 MD |
18 | * |
19 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
20 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
21 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
22 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
23 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
24 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | |
25 | * SOFTWARE. | |
8c4127c5 MD |
26 | */ |
27 | ||
4318ae1b | 28 | #include <lttng/bug.h> |
993e8a49 | 29 | #include <unistd.h> |
8e3484cf | 30 | #include <limits.h> |
8c4127c5 | 31 | |
b72687b8 MJ |
32 | #ifdef __FreeBSD__ |
33 | #include <machine/param.h> | |
8e3484cf MD |
34 | #endif |
35 | ||
b72687b8 MJ |
36 | #ifdef _SC_PAGE_SIZE |
37 | #define LTTNG_UST_PAGE_SIZE sysconf(_SC_PAGE_SIZE) | |
38 | #elif defined(PAGE_SIZE) | |
39 | #define LTTNG_UST_PAGE_SIZE PAGE_SIZE | |
40 | #else | |
41 | #error "Please add page size detection for your OS." | |
d6324154 | 42 | #endif |
b72687b8 MJ |
43 | |
44 | #define LTTNG_UST_PAGE_MASK (~(LTTNG_UST_PAGE_SIZE - 1)) | |
45 | ||
46 | #define __LTTNG_UST_ALIGN_MASK(v, mask) (((v) + (mask)) & ~(mask)) | |
47 | #define LTTNG_UST_ALIGN(v, align) __LTTNG_UST_ALIGN_MASK(v, (__typeof__(v)) (align) - 1) | |
48 | #define LTTNG_UST_PAGE_ALIGN(addr) LTTNG_UST_ALIGN(addr, LTTNG_UST_PAGE_SIZE) | |
8c4127c5 MD |
49 | |
50 | /** | |
b72687b8 MJ |
51 | * lttng_ust_offset_align - Calculate the offset needed to align an object on |
52 | * its natural alignment towards higher addresses. | |
8c4127c5 MD |
53 | * @align_drift: object offset from an "alignment"-aligned address. |
54 | * @alignment: natural object alignment. Must be non-zero, power of 2. | |
55 | * | |
56 | * Returns the offset that must be added to align towards higher | |
57 | * addresses. | |
58 | */ | |
b72687b8 | 59 | #define lttng_ust_offset_align(align_drift, alignment) \ |
8c4127c5 | 60 | ({ \ |
3f12fcef | 61 | LTTNG_BUILD_RUNTIME_BUG_ON((alignment) == 0 \ |
8c4127c5 MD |
62 | || ((alignment) & ((alignment) - 1))); \ |
63 | (((alignment) - (align_drift)) & ((alignment) - 1)); \ | |
64 | }) | |
65 | ||
66 | /** | |
b72687b8 MJ |
67 | * lttng_ust_offset_align_floor - Calculate the offset needed to align an |
68 | * object on its natural alignment towards lower addresses. | |
8c4127c5 MD |
69 | * @align_drift: object offset from an "alignment"-aligned address. |
70 | * @alignment: natural object alignment. Must be non-zero, power of 2. | |
71 | * | |
72 | * Returns the offset that must be substracted to align towards lower addresses. | |
73 | */ | |
b72687b8 | 74 | #define lttng_ust_offset_align_floor(align_drift, alignment) \ |
8c4127c5 | 75 | ({ \ |
3f12fcef | 76 | LTTNG_BUILD_RUNTIME_BUG_ON((alignment) == 0 \ |
8c4127c5 | 77 | || ((alignment) & ((alignment) - 1))); \ |
bf76f1ea | 78 | (((align_drift) - (alignment)) & ((alignment) - 1)); \ |
8c4127c5 MD |
79 | }) |
80 | ||
b72687b8 MJ |
81 | /* |
82 | * Non-namespaced defines for backwards compatibility, | |
83 | * introduced in 2.13, should be removed in the future. | |
84 | */ | |
85 | ||
86 | /* Cygwin limits.h defines its own PAGE_SIZE */ | |
87 | #ifndef PAGE_SIZE | |
88 | #define PAGE_SIZE LTTNG_UST_PAGE_SIZE | |
89 | #endif | |
90 | ||
91 | /* FreeBSD and macOS defines their own PAGE_MASK. */ | |
92 | #ifndef PAGE_MASK | |
93 | #define PAGE_MASK LTTNG_UST_PAGE_MASK | |
94 | #endif | |
95 | ||
96 | /* FreeBSD machine/param.h defines its own ALIGN */ | |
97 | #ifndef ALIGN | |
98 | #define ALIGN LTTNG_UST_ALIGN | |
99 | #endif | |
100 | ||
101 | #ifndef PAGE_ALIGN | |
102 | #define PAGE_ALIGN LTTNG_UST_PAGE_ALIGN | |
103 | #endif | |
104 | ||
105 | #ifndef offset_align | |
106 | #define offset_align lttng_ust_offset_align | |
107 | #endif | |
108 | ||
109 | #ifndef offset_align_floor | |
110 | #define offset_align_floor lttng_ust_offset_align_floor | |
111 | #endif | |
112 | ||
8c4127c5 | 113 | #endif /* _UST_ALIGN_H */ |