projects / lttng-ust.git / blame
| Commit | Line | Data |
|---|---|---|
| 8c4127c5 | 1 | /* |
| c0c0989a | 2 | * SPDX-License-Identifier: MIT |
| a60d70e6 | 3 | * |
| c0c0989a | 4 | * Copyright (C) 2010-2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 8c4127c5 MD |
5 | */ |
| 6 | ||
| c0c0989a MJ |
7 | #ifndef _UST_ALIGN_H |
| 8 | #define _UST_ALIGN_H | |
| 9 | ||
| 4318ae1b | 10 | #include <lttng/bug.h> |
| 993e8a49 | 11 | #include <unistd.h> |
| 8e3484cf | 12 | #include <limits.h> |
| 8c4127c5 | 13 | |
| b72687b8 MJ |
14 | #ifdef __FreeBSD__ |
| 15 | #include <machine/param.h> | |
| 8e3484cf MD |
16 | #endif |
| 17 | ||
| b72687b8 MJ |
18 | #ifdef _SC_PAGE_SIZE |
| 19 | #define LTTNG_UST_PAGE_SIZE sysconf(_SC_PAGE_SIZE) | |
| 20 | #elif defined(PAGE_SIZE) | |
| 21 | #define LTTNG_UST_PAGE_SIZE PAGE_SIZE | |
| 22 | #else | |
| 23 | #error "Please add page size detection for your OS." | |
| d6324154 | 24 | #endif |
| b72687b8 MJ |
25 | |
| 26 | #define LTTNG_UST_PAGE_MASK (~(LTTNG_UST_PAGE_SIZE - 1)) | |
| 27 | ||
| 28 | #define __LTTNG_UST_ALIGN_MASK(v, mask) (((v) + (mask)) & ~(mask)) | |
| 29 | #define LTTNG_UST_ALIGN(v, align) __LTTNG_UST_ALIGN_MASK(v, (__typeof__(v)) (align) - 1) | |
| 30 | #define LTTNG_UST_PAGE_ALIGN(addr) LTTNG_UST_ALIGN(addr, LTTNG_UST_PAGE_SIZE) | |
| 8c4127c5 MD |
31 | |
| 32 | /** | |
| b72687b8 MJ |
33 | * lttng_ust_offset_align - Calculate the offset needed to align an object on |
| 34 | * its natural alignment towards higher addresses. | |
| 8c4127c5 MD |
35 | * @align_drift: object offset from an "alignment"-aligned address. |
| 36 | * @alignment: natural object alignment. Must be non-zero, power of 2. | |
| 37 | * | |
| 38 | * Returns the offset that must be added to align towards higher | |
| 39 | * addresses. | |
| 40 | */ | |
| b72687b8 | 41 | #define lttng_ust_offset_align(align_drift, alignment) \ |
| 8c4127c5 | 42 | ({ \ |
| 3f12fcef | 43 | LTTNG_BUILD_RUNTIME_BUG_ON((alignment) == 0 \ |
| 8c4127c5 MD |
44 | || ((alignment) & ((alignment) - 1))); \ |
| 45 | (((alignment) - (align_drift)) & ((alignment) - 1)); \ | |
| 46 | }) | |
| 47 | ||
| 48 | /** | |
| b72687b8 MJ |
49 | * lttng_ust_offset_align_floor - Calculate the offset needed to align an |
| 50 | * object on its natural alignment towards lower addresses. | |
| 8c4127c5 MD |
51 | * @align_drift: object offset from an "alignment"-aligned address. |
| 52 | * @alignment: natural object alignment. Must be non-zero, power of 2. | |
| 53 | * | |
| 54 | * Returns the offset that must be substracted to align towards lower addresses. | |
| 55 | */ | |
| b72687b8 | 56 | #define lttng_ust_offset_align_floor(align_drift, alignment) \ |
| 8c4127c5 | 57 | ({ \ |
| 3f12fcef | 58 | LTTNG_BUILD_RUNTIME_BUG_ON((alignment) == 0 \ |
| 8c4127c5 | 59 | || ((alignment) & ((alignment) - 1))); \ |
| bf76f1ea | 60 | (((align_drift) - (alignment)) & ((alignment) - 1)); \ |
| 8c4127c5 MD |
61 | }) |
| 62 | ||
| b72687b8 MJ |
63 | /* |
| 64 | * Non-namespaced defines for backwards compatibility, | |
| 65 | * introduced in 2.13, should be removed in the future. | |
| 66 | */ | |
| 67 | ||
| 68 | /* Cygwin limits.h defines its own PAGE_SIZE */ | |
| 69 | #ifndef PAGE_SIZE | |
| 70 | #define PAGE_SIZE LTTNG_UST_PAGE_SIZE | |
| 71 | #endif | |
| 72 | ||
| 73 | /* FreeBSD and macOS defines their own PAGE_MASK. */ | |
| 74 | #ifndef PAGE_MASK | |
| 75 | #define PAGE_MASK LTTNG_UST_PAGE_MASK | |
| 76 | #endif | |
| 77 | ||
| 78 | /* FreeBSD machine/param.h defines its own ALIGN */ | |
| 79 | #ifndef ALIGN | |
| 80 | #define ALIGN LTTNG_UST_ALIGN | |
| 81 | #endif | |
| 82 | ||
| 83 | #ifndef PAGE_ALIGN | |
| 84 | #define PAGE_ALIGN LTTNG_UST_PAGE_ALIGN | |
| 85 | #endif | |
| 86 | ||
| 87 | #ifndef offset_align | |
| 88 | #define offset_align lttng_ust_offset_align | |
| 89 | #endif | |
| 90 | ||
| 91 | #ifndef offset_align_floor | |
| 92 | #define offset_align_floor lttng_ust_offset_align_floor | |
| 93 | #endif | |
| 94 | ||
| 8c4127c5 | 95 | #endif /* _UST_ALIGN_H */ |