1 | /* |
2 | * Copyright (C) 2018 Apple Inc. All rights reserved. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
7 | * 1. Redistributions of source code must retain the above copyright |
8 | * notice, this list of conditions and the following disclaimer. |
9 | * 2. Redistributions in binary form must reproduce the above copyright |
10 | * notice, this list of conditions and the following disclaimer in the |
11 | * documentation and/or other materials provided with the distribution. |
12 | * |
13 | * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
14 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
15 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
17 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
18 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
19 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
20 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
21 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
23 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #include "PerProcess.h" |
27 | |
28 | #include "VMAllocate.h" |
29 | #include <stdio.h> |
30 | |
31 | namespace bmalloc { |
32 | |
33 | static constexpr unsigned tableSize = 100; |
34 | static constexpr bool verbose = false; |
35 | |
36 | static Mutex s_mutex; |
37 | |
38 | static char* s_bumpBase; |
39 | static size_t s_bumpOffset; |
40 | static size_t s_bumpLimit; |
41 | |
42 | static PerProcessData* s_table[tableSize]; |
43 | |
44 | // Returns zero-filled memory by virtual of using vmAllocate. |
45 | static void* allocate(size_t size, size_t alignment) |
46 | { |
47 | s_bumpOffset = roundUpToMultipleOf(alignment, s_bumpOffset); |
48 | void* result = s_bumpBase + s_bumpOffset; |
49 | s_bumpOffset += size; |
50 | if (s_bumpOffset <= s_bumpLimit) |
51 | return result; |
52 | |
53 | size_t allocationSize = vmSize(size); |
54 | void* allocation = vmAllocate(allocationSize); |
55 | s_bumpBase = static_cast<char*>(allocation); |
56 | s_bumpOffset = 0; |
57 | s_bumpLimit = allocationSize; |
58 | return allocate(size, alignment); |
59 | } |
60 | |
61 | PerProcessData* getPerProcessData(unsigned hash, const char* disambiguator, size_t size, size_t alignment) |
62 | { |
63 | std::lock_guard<Mutex> lock(s_mutex); |
64 | |
65 | PerProcessData*& bucket = s_table[hash % tableSize]; |
66 | |
67 | for (PerProcessData* data = bucket; data; data = data->next) { |
68 | if (!strcmp(data->disambiguator, disambiguator)) { |
69 | if (verbose) |
70 | fprintf(stderr, "%d: Using existing %s\n" , getpid(), disambiguator); |
71 | RELEASE_BASSERT(data->size == size); |
72 | RELEASE_BASSERT(data->alignment == alignment); |
73 | return data; |
74 | } |
75 | } |
76 | |
77 | if (verbose) |
78 | fprintf(stderr, "%d: Creating new %s\n" , getpid(), disambiguator); |
79 | void* rawDataPtr = allocate(sizeof(PerProcessData), std::alignment_of<PerProcessData>::value); |
80 | PerProcessData* data = static_cast<PerProcessData*>(rawDataPtr); |
81 | data->disambiguator = disambiguator; |
82 | data->memory = allocate(size, alignment); |
83 | data->size = size; |
84 | data->alignment = alignment; |
85 | data->next = bucket; |
86 | bucket = data; |
87 | return data; |
88 | } |
89 | |
90 | } // namespace bmalloc |
91 | |
92 | |