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
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <android-base/logging.h>
#include <android-base/unique_fd.h>
#include "meminfo_private.h"
using unique_fd = ::android::base::unique_fd;
namespace android {
namespace meminfo {
static inline off64_t pfn_to_idle_bitmap_offset(uint64_t pfn) {
return static_cast<off64_t>((pfn >> 6) << 3);
}
uint64_t pagesize(void) {
static uint64_t pagesize = sysconf(_SC_PAGE_SIZE);
return pagesize;
}
bool PageAcct::InitPageAcct(bool pageidle_enable) {
if (pageidle_enable && !PageAcct::KernelHasPageIdle()) {
LOG(ERROR) << "Idle page tracking is not supported by the kernel";
return false;
}
if (kpagecount_fd_ < 0) {
unique_fd count_fd(TEMP_FAILURE_RETRY(open("/proc/kpagecount", O_RDONLY | O_CLOEXEC)));
if (count_fd < 0) {
PLOG(ERROR) << "Failed to open /proc/kpagecount";
return false;
}
kpagecount_fd_ = std::move(count_fd);
}
if (kpageflags_fd_ < 0) {
unique_fd flags_fd(TEMP_FAILURE_RETRY(open("/proc/kpageflags", O_RDONLY | O_CLOEXEC)));
if (flags_fd < 0) {
PLOG(ERROR) << "Failed to open /proc/kpageflags";
return false;
}
kpageflags_fd_ = std::move(flags_fd);
}
if (pageidle_enable && pageidle_fd_ < 0) {
unique_fd idle_fd(
TEMP_FAILURE_RETRY(open("/sys/kernel/mm/page_idle/bitmap", O_RDWR | O_CLOEXEC)));
if (idle_fd < 0) {
PLOG(ERROR) << "Failed to open page idle bitmap";
return false;
}
pageidle_fd_ = std::move(idle_fd);
}
return true;
}
bool PageAcct::PageFlags(uint64_t pfn, uint64_t* flags) {
if (!flags) return false;
if (kpageflags_fd_ < 0) {
if (!InitPageAcct()) return false;
}
if (pread64(kpageflags_fd_, flags, sizeof(uint64_t), pfn * sizeof(uint64_t)) < 0) {
PLOG(ERROR) << "Failed to read page flags for page " << pfn;
return false;
}
return true;
}
bool PageAcct::PageMapCount(uint64_t pfn, uint64_t* mapcount) {
if (!mapcount) return false;
if (kpagecount_fd_ < 0) {
if (!InitPageAcct()) return false;
}
if (pread64(kpagecount_fd_, mapcount, sizeof(uint64_t), pfn * sizeof(uint64_t)) < 0) {
PLOG(ERROR) << "Failed to read map count for page " << pfn;
return false;
}
return true;
}
int PageAcct::IsPageIdle(uint64_t pfn) {
if (pageidle_fd_ < 0) {
if (!InitPageAcct(true)) return -EOPNOTSUPP;
}
int idle_status = MarkPageIdle(pfn);
if (idle_status) return idle_status;
return GetPageIdle(pfn);
}
int PageAcct::MarkPageIdle(uint64_t pfn) const {
off64_t offset = pfn_to_idle_bitmap_offset(pfn);
// set the bit corresponding to page frame
uint64_t idle_bits = 1ULL << (pfn % 64);
if (pwrite64(pageidle_fd_, &idle_bits, sizeof(uint64_t), offset) < 0) {
PLOG(ERROR) << "Failed to write page idle bitmap for page " << pfn;
return -errno;
}
return 0;
}
int PageAcct::GetPageIdle(uint64_t pfn) const {
off64_t offset = pfn_to_idle_bitmap_offset(pfn);
uint64_t idle_bits;
if (pread64(pageidle_fd_, &idle_bits, sizeof(uint64_t), offset) < 0) {
PLOG(ERROR) << "Failed to read page idle bitmap for page " << pfn;
return -errno;
}
return !!(idle_bits & (1ULL << (pfn % 64)));
}
// Public methods
bool page_present(uint64_t pagemap_val) {
return PAGE_PRESENT(pagemap_val);
}
bool page_swapped(uint64_t pagemap_val) {
return PAGE_SWAPPED(pagemap_val);
}
uint64_t page_pfn(uint64_t pagemap_val) {
return PAGE_PFN(pagemap_val);
}
} // namespace meminfo
} // namespace android
|
