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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
|
/*
* Copyright (c) 2021 Cisco Systems and/or its affiliates.
* 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.
*/
/*Go-FUSE allows us to define the behaviour of our filesystem by recoding any primitive function we need.
*The structure of the filesystem is constructed as a tree.
*Each type of nodes (root, directory, file) follows its own prmitives.
*/
package main
import (
"context"
"fmt"
"path"
"path/filepath"
"strings"
"syscall"
"time"
"github.com/hanwen/go-fuse/v2/fs"
"github.com/hanwen/go-fuse/v2/fuse"
"git.fd.io/govpp.git/adapter"
"git.fd.io/govpp.git/adapter/statsclient"
)
func updateDir(ctx context.Context, n *fs.Inode, cl *statsclient.StatsClient, dirPath string) syscall.Errno {
stats, err := cl.PrepareDir(dirPath)
if err != nil {
LogMsg(fmt.Sprintf("Listing stats index failed: %v\n", err))
return syscall.EAGAIN
}
n.Operations().(*dirNode).epoch = stats.Epoch
n.RmAllChildren()
for _, entry := range stats.Entries {
localPath := strings.TrimPrefix(string(entry.Name), dirPath)
dirPath, base := filepath.Split(localPath)
parent := n
for _, component := range strings.Split(dirPath, "/") {
if len(component) == 0 {
continue
}
child := parent.GetChild(component)
if child == nil {
child = parent.NewInode(ctx, &dirNode{client: cl, epoch: stats.Epoch},
fs.StableAttr{Mode: fuse.S_IFDIR})
parent.AddChild(component, child, true)
} else {
child.Operations().(*dirNode).epoch = stats.Epoch
}
parent = child
}
filename := strings.Replace(base, " ", "_", -1)
child := parent.GetChild(filename)
if child == nil {
child := parent.NewPersistentInode(ctx, &statNode{client: cl, index: entry.Index}, fs.StableAttr{})
parent.AddChild(filename, child, true)
}
}
return 0
}
func getCounterContent(index uint32, client *statsclient.StatsClient) (content string, status syscall.Errno) {
content = ""
statsDir, err := client.PrepareDirOnIndex(index)
if err != nil {
LogMsg(fmt.Sprintf("Dumping stats on index failed: %v\n", err))
return content, syscall.EAGAIN
}
if len(statsDir.Entries) != 1 {
return content, syscall.ENOENT
}
result := statsDir.Entries[0]
if result.Data == nil {
return content, 0
}
switch result.Type {
case adapter.ScalarIndex:
stats := result.Data.(adapter.ScalarStat)
content = fmt.Sprintf("%.2f\n", stats)
case adapter.ErrorIndex:
stats := result.Data.(adapter.ErrorStat)
content = fmt.Sprintf("%-16s%s\n", "Index", "Count")
for i, value := range stats {
content += fmt.Sprintf("%-16d%d\n", i, value)
}
case adapter.SimpleCounterVector:
stats := result.Data.(adapter.SimpleCounterStat)
content = fmt.Sprintf("%-16s%-16s%s\n", "Thread", "Index", "Packets")
for i, vector := range stats {
for j, value := range vector {
content += fmt.Sprintf("%-16d%-16d%d\n", i, j, value)
}
}
case adapter.CombinedCounterVector:
stats := result.Data.(adapter.CombinedCounterStat)
content = fmt.Sprintf("%-16s%-16s%-16s%s\n", "Thread", "Index", "Packets", "Bytes")
for i, vector := range stats {
for j, value := range vector {
content += fmt.Sprintf("%-16d%-16d%-16d%d\n", i, j, value[0], value[1])
}
}
case adapter.NameVector:
stats := result.Data.(adapter.NameStat)
content = fmt.Sprintf("%-16s%s\n", "Index", "Name")
for i, value := range stats {
content += fmt.Sprintf("%-16d%s\n", i, string(value))
}
default:
content = fmt.Sprintf("Unknown stat type: %d\n", result.Type)
//For now, the empty type (file deleted) is not implemented in GoVPP
return content, syscall.ENOENT
}
return content, fs.OK
}
//The dirNode structure represents directories
type dirNode struct {
fs.Inode
client *statsclient.StatsClient
epoch int64
}
var _ = (fs.NodeOpendirer)((*dirNode)(nil))
var _ = (fs.NodeGetattrer)((*dirNode)(nil))
var _ = (fs.NodeOnAdder)((*dirNode)(nil))
func (dn *dirNode) OnAdd(ctx context.Context) {
if dn.Inode.IsRoot() {
updateDir(ctx, &dn.Inode, dn.client, "/")
}
}
func (dn *dirNode) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
out.Mtime = uint64(time.Now().Unix())
out.Atime = out.Mtime
out.Ctime = out.Mtime
return 0
}
func (dn *dirNode) Opendir(ctx context.Context) syscall.Errno {
var status syscall.Errno = syscall.F_OK
var sleepTime time.Duration = 10 * time.Millisecond
newEpoch, inProgress := dn.client.GetEpoch()
for inProgress {
newEpoch, inProgress = dn.client.GetEpoch()
time.Sleep(sleepTime)
sleepTime = sleepTime * 2
}
//We check that the directory epoch is up to date
if dn.epoch != newEpoch {
//directoryPath is the path to the current directory from root
directoryPath := path.Clean("/" + dn.Inode.Path(nil) + "/")
status = updateDir(ctx, &dn.Inode, dn.client, directoryPath)
}
return status
}
//The statNode structure represents counters
type statNode struct {
fs.Inode
client *statsclient.StatsClient
index uint32
}
var _ = (fs.NodeOpener)((*statNode)(nil))
var _ = (fs.NodeGetattrer)((*statNode)(nil))
func (fh *statNode) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
out.Mtime = uint64(time.Now().Unix())
out.Atime = out.Mtime
out.Ctime = out.Mtime
return 0
}
//When a file is opened, the correpsonding counter value is dumped and a file handle is created
func (sn *statNode) Open(ctx context.Context, flags uint32) (fs.FileHandle, uint32, syscall.Errno) {
content, status := getCounterContent(sn.index, sn.client)
if status == syscall.ENOENT {
_, parent := sn.Inode.Parent()
parent.RmChild(sn.Inode.Path(parent))
}
return &statFH{data: []byte(content)}, fuse.FOPEN_DIRECT_IO, status
}
/* The statFH structure aims at dislaying the counters dynamically.
* It allows the Kernel to read data as I/O without having to specify files sizes, as they may evolve dynamically.
*/
type statFH struct {
data []byte
}
var _ = (fs.FileReader)((*statFH)(nil))
func (fh *statFH) Read(ctx context.Context, data []byte, off int64) (fuse.ReadResult, syscall.Errno) {
end := int(off) + len(data)
if end > len(fh.data) {
end = len(fh.data)
}
return fuse.ReadResultData(fh.data[off:end]), fs.OK
}
//NewStatsFileSystem creates the fs for the stat segment.
func NewStatsFileSystem(sc *statsclient.StatsClient) (root fs.InodeEmbedder, err error) {
return &dirNode{client: sc}, nil
}
|