aboutsummaryrefslogtreecommitdiffstats
path: root/vespamalloc/src/vespamalloc/malloc/mmappool.cpp
blob: cee709ed0ed579f5910947ee164ee37a005a4149 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include "mmappool.h"
#include "common.h"
#include <sys/mman.h>
#include <algorithm>
#include <unistd.h>

namespace vespamalloc {

MMapPool::MMapPool()
    : _page_size(getpagesize()),
      _huge_flags((getenv("VESPA_USE_HUGEPAGES") != nullptr) ? MAP_HUGETLB : 0),
      _peakBytes(0ul),
      _currentBytes(0ul),
      _count(0),
      _mutex(),
      _mappings()
{ }

MMapPool::~MMapPool() {
    ASSERT_STACKTRACE(_mappings.empty());
}

size_t
MMapPool::getNumMappings() const {
    std::lock_guard guard(_mutex);
    return _mappings.size();
}

size_t
MMapPool::getMmappedBytes() const {
    std::lock_guard guard(_mutex);
    return _currentBytes;
}

size_t
MMapPool::getMmappedBytesPeak() const {
    std::lock_guard guard(_mutex);
    return _peakBytes;
}

void *
MMapPool::mmap(size_t sz) {
    void * buf(nullptr);
    ASSERT_STACKTRACE((sz & (_page_size - 1)) == 0);
    if (sz > 0) {
        const int flags(MAP_ANON | MAP_PRIVATE);
        const int prot(PROT_READ | PROT_WRITE);
        size_t mmapId = _count.fetch_add(1);
        if (sz >= _G_bigBlockLimit) {
            fprintf(_G_logFile, "mmap %ld of size %ld from : ", mmapId, sz);
            logStackTrace();
        }
        buf = ::mmap(nullptr, sz, prot, flags | _huge_flags, -1, 0);
        if (buf == MAP_FAILED) {
            if (!_has_hugepage_failure_just_happened) {
                _has_hugepage_failure_just_happened = true;
            }
            buf = ::mmap(nullptr, sz, prot, flags, -1, 0);
            if (buf == MAP_FAILED) {
                fprintf(_G_logFile, "Failed mmaping anonymous of size %ld errno(%d) from : ", sz, errno);
                logStackTrace();
                abort();
            }
        } else {
            if (_has_hugepage_failure_just_happened) {
                _has_hugepage_failure_just_happened = false;
            }
        }
#ifdef __linux__
        if (madvise(buf, sz, MADV_HUGEPAGE) != 0) {
            // Just an advise, not everyone will listen...
        }
        if (sz >= _G_bigBlockLimit) {
            if (madvise(buf, sz, MADV_DONTDUMP) != 0) {
                std::error_code ec(errno, std::system_category());
                fprintf(_G_logFile, "Failed madvise(%p, %ld, MADV_DONTDUMP) = '%s'\n", buf, sz,
                    ec.message().c_str());
            }
        }
#endif
        std::lock_guard guard(_mutex);
        auto [it, inserted] = _mappings.insert(std::make_pair(buf, MMapInfo(mmapId, sz)));
        ASSERT_STACKTRACE(inserted);
        _currentBytes += sz;
        _peakBytes = std::max(_peakBytes, _currentBytes);
        if (sz >= _G_bigBlockLimit) {
            fprintf(_G_logFile, "%ld mappings of accumulated size %ld\n", _mappings.size(), _currentBytes);
        }
    }
    return buf;
}

void
MMapPool::unmap(void * ptr) {
    size_t sz;
    {
        std::lock_guard guard(_mutex);
        auto found = _mappings.find(ptr);
        if (found == _mappings.end()) {
            fprintf(_G_logFile, "Not able to unmap %p as it is not registered: ", ptr);
            logStackTrace();
            abort();
        }
        sz = found->second._sz;
        _mappings.erase(found);
        _currentBytes -= sz;
    }
    int munmap_ok = ::munmap(ptr, sz);
    ASSERT_STACKTRACE(munmap_ok == 0);
}

size_t
MMapPool::get_size(void * ptr) const {
    std::lock_guard guard(_mutex);
    auto found = _mappings.find(ptr);
    ASSERT_STACKTRACE(found != _mappings.end());
    return found->second._sz;
}

void
MMapPool::info(FILE * os, size_t) const {
    fprintf(os, "MMapPool has %zu mappings, accumulated count is %lu,  with a total of %zu mapped bytes\n",
            getNumMappings(), _count.load(std::memory_order_relaxed), getMmappedBytes());
    std::lock_guard guard(_mutex);
    size_t i(0);
    for (const auto & e : _mappings) {
        fprintf(os, "%4zu: (id=%zu, sz=%zu) = %p\n", i++, e.second._id, e.second._sz, e.first);
    }
}

}