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
|
// Copyright 2018 The containerd Authors.
// Copyright 2018 The gVisor Authors.
//
// 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
//
// https://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.
//go:build linux
// +build linux
package shim
import (
"context"
"fmt"
"sync"
"github.com/containerd/cgroups"
"github.com/containerd/containerd/events"
"github.com/containerd/containerd/runtime"
"golang.org/x/sys/unix"
)
func newOOMEpoller(publisher events.Publisher) (*epoller, error) {
fd, err := unix.EpollCreate1(unix.EPOLL_CLOEXEC)
if err != nil {
return nil, err
}
return &epoller{
fd: fd,
publisher: publisher,
set: make(map[uintptr]*item),
}, nil
}
type epoller struct {
mu sync.Mutex
fd int
publisher events.Publisher
set map[uintptr]*item
}
type item struct {
id string
cg cgroups.Cgroup
}
func (e *epoller) Close() error {
return unix.Close(e.fd)
}
func (e *epoller) run(ctx context.Context) {
var events [128]unix.EpollEvent
for {
select {
case <-ctx.Done():
e.Close()
return
default:
n, err := unix.EpollWait(e.fd, events[:], -1)
if err != nil {
if err == unix.EINTR || err == unix.EAGAIN {
continue
}
// Should not happen.
panic(fmt.Errorf("cgroups: epoll wait: %w", err))
}
for i := 0; i < n; i++ {
e.process(ctx, uintptr(events[i].Fd))
}
}
}
}
func (e *epoller) add(id string, cg cgroups.Cgroup) error {
e.mu.Lock()
defer e.mu.Unlock()
fd, err := cg.OOMEventFD()
if err != nil {
return err
}
e.set[fd] = &item{
id: id,
cg: cg,
}
event := unix.EpollEvent{
Fd: int32(fd),
Events: unix.EPOLLHUP | unix.EPOLLIN | unix.EPOLLERR,
}
return unix.EpollCtl(e.fd, unix.EPOLL_CTL_ADD, int(fd), &event)
}
func (e *epoller) process(ctx context.Context, fd uintptr) {
flush(fd)
e.mu.Lock()
i, ok := e.set[fd]
if !ok {
e.mu.Unlock()
return
}
e.mu.Unlock()
if i.cg.State() == cgroups.Deleted {
e.mu.Lock()
delete(e.set, fd)
e.mu.Unlock()
unix.Close(int(fd))
return
}
if err := e.publisher.Publish(ctx, runtime.TaskOOMEventTopic, &TaskOOM{
ContainerID: i.id,
}); err != nil {
// Should not happen.
panic(fmt.Errorf("publish OOM event: %w", err))
}
}
func flush(fd uintptr) error {
var buf [8]byte
_, err := unix.Read(int(fd), buf[:])
return err
}
|
