1
// Copyright 2009 The Go Authors. All rights reserved.
2
// Use of this source code is governed by a BSD-style
3
// license that can be found in the LICENSE file.
13
static void* threadentry(void*);
14
static void (*setmg_gcc)(void*, void*);
16
// TCB_SIZE is sizeof(struct thread_control_block),
17
// as defined in /usr/src/lib/librthread/tcb.h
18
#define TCB_SIZE (4 * sizeof(void *))
19
#define TLS_SIZE (2 * sizeof(void *))
21
void *__get_tcb(void);
22
void __set_tcb(void *);
24
static int (*sys_pthread_create)(pthread_t *thread, const pthread_attr_t *attr,
25
void *(*start_routine)(void *), void *arg);
28
void *(*func)(void *);
33
tcb_fixup(int mainthread)
35
void *newtcb, *oldtcb;
37
// The OpenBSD ld.so(1) does not currently support PT_TLS. As a result,
38
// we need to allocate our own TLS space while preserving the existing
39
// TCB that has been setup via librthread.
41
newtcb = malloc(TCB_SIZE + TLS_SIZE);
45
// The signal trampoline expects the TLS slots to be zeroed.
46
bzero(newtcb, TLS_SIZE);
49
bcopy(oldtcb, newtcb + TLS_SIZE, TCB_SIZE);
50
__set_tcb(newtcb + TLS_SIZE);
52
// NOTE(jsing, minux): we can't free oldtcb without causing double-free
53
// problem. so newtcb will be memory leaks. Get rid of this when OpenBSD
54
// has proper support for PT_TLS.
58
thread_start_wrapper(void *arg)
60
struct thread_args args = *(struct thread_args *)arg;
65
return args.func(args.arg);
69
pthread_create(pthread_t *thread, const pthread_attr_t *attr,
70
void *(*start_routine)(void *), void *arg)
72
struct thread_args *p;
74
p = malloc(sizeof(*p));
79
p->func = start_routine;
82
return sys_pthread_create(thread, attr, thread_start_wrapper, p);
86
x_cgo_init(G *g, void (*setmg)(void*, void*))
93
pthread_attr_init(&attr);
94
pthread_attr_getstacksize(&attr, &size);
95
g->stackguard = (uintptr)&attr - size + 4096;
96
pthread_attr_destroy(&attr);
98
// Locate symbol for the system pthread_create function.
99
handle = dlopen("libpthread.so", RTLD_LAZY);
101
fprintf(stderr, "dlopen: failed to load libpthread: %s\n", dlerror());
104
sys_pthread_create = dlsym(handle, "pthread_create");
105
if(sys_pthread_create == NULL) {
106
fprintf(stderr, "dlsym: failed to find pthread_create: %s\n", dlerror());
116
_cgo_sys_thread_start(ThreadStart *ts)
125
sigprocmask(SIG_SETMASK, &ign, &oset);
127
pthread_attr_init(&attr);
128
pthread_attr_getstacksize(&attr, &size);
130
ts->g->stackguard = size;
131
err = sys_pthread_create(&p, &attr, threadentry, ts);
133
sigprocmask(SIG_SETMASK, &oset, nil);
136
fprintf(stderr, "runtime/cgo: pthread_create failed: %s\n", strerror(err));
148
ts = *(ThreadStart*)v;
151
ts.g->stackbase = (uintptr)&ts;
154
* _cgo_sys_thread_start set stackguard to stack size;
155
* change to actual guard pointer.
157
ts.g->stackguard = (uintptr)&ts - ts.g->stackguard + 4096;
162
setmg_gcc((void*)ts.m, (void*)ts.g);
164
crosscall_amd64(ts.fn);