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
|
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package runtime
import (
"internal/goarch"
"unsafe"
)
type mOS struct{}
//go:noescape
//extern _umtx_op
func sys_umtx_op(addr *uint32, mode int32, val uint32, uaddr1 uinptr, ts *umtx_time) int32
//go:noescape
//extern sysctl
func sysctl(*uint32, uint32, *byte, *uintptr, *byte, uintptr) int32
const (
_CTL_MAXNAME = 24
_CPU_LEVEL_WHICH = 3
_CPU_WHICH_PID = 2
)
// From FreeBSD's <sys/sysctl.h>
const (
_CTL_HW = 6
_HW_PAGESIZE = 7
)
// Undocumented numbers from FreeBSD's lib/libc/gen/sysctlnametomib.c.
const (
_CTL_QUERY = 0
_CTL_QUERY_MIB = 3
)
// sysctlnametomib fill mib with dynamically assigned sysctl entries of name,
// return count of effected mib slots, return 0 on error.
func sysctlnametomib(name []byte, mib *[_CTL_MAXNAME]uint32) uint32 {
oid := [2]uint32{_CTL_QUERY, _CTL_QUERY_MIB}
miblen := uintptr(_CTL_MAXNAME)
if sysctl(&oid[0], 2, (*byte)(unsafe.Pointer(mib)), &miblen, (*byte)(unsafe.Pointer(&name[0])), (uintptr)(len(name))) < 0 {
return 0
}
miblen /= unsafe.Sizeof(uint32(0))
if miblen <= 0 {
return 0
}
return uint32(miblen)
}
const (
_CPU_CURRENT_PID = -1 // Current process ID.
)
//go:noescape
//extern cpuset_getaffinity
func cpuset_getaffinity(level int32, which int32, id int64, size uintptr, mask *byte) int32
//go:systemstack
func getncpu() int32 {
// Use a large buffer for the CPU mask. We're on the system
// stack, so this is fine, and we can't allocate memory for a
// dynamically-sized buffer at this point.
const maxCPUs = 64 * 1024
var mask [maxCPUs / 8]byte
var mib [_CTL_MAXNAME]uint32
// According to FreeBSD's /usr/src/sys/kern/kern_cpuset.c,
// cpuset_getaffinity return ERANGE when provided buffer size exceed the limits in kernel.
// Querying kern.smp.maxcpus to calculate maximum buffer size.
// See https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200802
// Variable kern.smp.maxcpus introduced at Dec 23 2003, revision 123766,
// with dynamically assigned sysctl entries.
miblen := sysctlnametomib([]byte("kern.smp.maxcpus"), &mib)
if miblen == 0 {
return 1
}
// Query kern.smp.maxcpus.
dstsize := uintptr(4)
maxcpus := uint32(0)
if sysctl(&mib[0], miblen, (*byte)(unsafe.Pointer(&maxcpus)), &dstsize, nil, 0) != 0 {
return 1
}
maskSize := int(maxcpus+7) / 8
if maskSize < goarch.PtrSize {
maskSize = goarch.PtrSize
}
if maskSize > uintptr(len(mask)) {
maskSize = uintptr(len(mask))
}
if cpuset_getaffinity(_CPU_LEVEL_WHICH, _CPU_WHICH_PID, _CPU_CURRENT_PID,
maskSize, (*byte)(unsafe.Pointer(&mask[0]))) != 0 {
return 1
}
n := int32(0)
for _, v := range mask[:maskSize] {
for v != 0 {
n += int32(v & 1)
v >>= 1
}
}
if n == 0 {
return 1
}
return n
}
func getPageSize() uintptr {
mib := [2]uint32{_CTL_HW, _HW_PAGESIZE}
out := uint32(0)
nout := unsafe.Sizeof(out)
ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
if ret >= 0 {
return uintptr(out)
}
return 0
}
// FreeBSD's umtx_op syscall is effectively the same as Linux's futex, and
// thus the code is largely similar. See Linux implementation
// and lock_futex.go for comments.
//go:nosplit
func futexsleep(addr *uint32, val uint32, ns int64) {
systemstack(func() {
futexsleep1(addr, val, ns)
})
}
func futexsleep1(addr *uint32, val uint32, ns int64) {
var utp *umtx_time
if ns >= 0 {
var ut umtx_time
ut._clockid = _CLOCK_MONOTONIC
ut._timeout.setNsec(ns)
utp = &ut
}
ret := sys_umtx_op(addr, _UMTX_OP_WAIT_UINT_PRIVATE, val, unsafe.Sizeof(*utp), utp)
if ret >= 0 || ret == -_EINTR || ret == -_ETIMEDOUT {
return
}
print("umtx_wait addr=", addr, " val=", val, " ret=", ret, "\n")
*(*int32)(unsafe.Pointer(uintptr(0x1005))) = 0x1005
}
//go:nosplit
func futexwakeup(addr *uint32, cnt uint32) {
ret := sys_umtx_op(addr, _UMTX_OP_WAKE_PRIVATE, cnt, 0, nil)
if ret >= 0 {
return
}
systemstack(func() {
print("umtx_wake_addr=", addr, " ret=", ret, "\n")
})
}
func osinit() {
ncpu = getncpu()
if physPageSize == 0 {
physPageSize = getPageSize()
}
}
func sysargs(argc int32, argv **byte) {
n := argc + 1
// skip over argv, envp to get to auxv
for argv_index(argv, n) != nil {
n++
}
// skip NULL separator
n++
// now argv+n is auxv
auxv := (*[1 << 28]uintptr)(add(unsafe.Pointer(argv), uintptr(n)*goarch.PtrSize))
sysauxv(auxv[:])
}
const (
_AT_NULL = 0 // Terminates the vector
_AT_PAGESZ = 6 // Page size in bytes
_AT_TIMEKEEP = 22 // Pointer to timehands.
_AT_HWCAP = 25 // CPU feature flags
_AT_HWCAP2 = 26 // CPU feature flags 2
)
func sysauxv(auxv []uintptr) {
for i := 0; auxv[i] != _AT_NULL; i += 2 {
tag, val := auxv[i], auxv[i+1]
switch tag {
// _AT_NCPUS from auxv shouldn't be used due to golang.org/issue/15206
case _AT_PAGESZ:
physPageSize = val
case _AT_TIMEKEEP:
timekeepSharedPage = (*vdsoTimekeep)(unsafe.Pointer(val))
}
archauxv(tag, val)
}
}
|
