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// Use of this source file is governed by a BSD-style
// license that can be found in the LICENSE file.`
#include "runtime.h"
#include "defs.h"
#include "os.h"
#include "stack.h"
extern SigTab runtime·sigtab[];
extern int64 runtime·rfork_thread(int32 flags, void *stack, M *m, G *g, void (*fn)(void));
extern void runtime·sys_sched_yield(void);
// Basic spinlocks using CAS. We can improve on these later.
static void
lock(Lock *l)
{
uint32 v;
int32 ret;
for(;;) {
if(runtime·cas(&l->key, 0, 1))
return;
runtime·sys_sched_yield();
}
}
static void
unlock(Lock *l)
{
uint32 v;
int32 ret;
for (;;) {
v = l->key;
if((v&1) == 0)
runtime·throw("unlock of unlocked lock");
if(runtime·cas(&l->key, v, 0))
break;
}
}
void
runtime·lock(Lock *l)
{
if(m->locks < 0)
runtime·throw("lock count");
m->locks++;
lock(l);
}
void
runtime·unlock(Lock *l)
{
m->locks--;
if(m->locks < 0)
runtime·throw("lock count");
unlock(l);
}
// Event notifications.
void
runtime·noteclear(Note *n)
{
n->lock.key = 0;
lock(&n->lock);
}
void
runtime·notesleep(Note *n)
{
lock(&n->lock);
unlock(&n->lock);
}
void
runtime·notewakeup(Note *n)
{
unlock(&n->lock);
}
// From OpenBSD's sys/param.h
#define RFPROC (1<<4) /* change child (else changes curproc) */
#define RFMEM (1<<5) /* share `address space' */
#define RFNOWAIT (1<<6) /* parent need not wait() on child */
#define RFTHREAD (1<<13) /* create a thread, not a process */
void
runtime·newosproc(M *m, G *g, void *stk, void (*fn)(void))
{
int32 flags;
int32 ret;
flags = RFPROC | RFTHREAD | RFMEM | RFNOWAIT;
if (0) {
runtime·printf(
"newosproc stk=%p m=%p g=%p fn=%p id=%d/%d ostk=%p\n",
stk, m, g, fn, m->id, m->tls[0], &m);
}
m->tls[0] = m->id; // so 386 asm can find it
if((ret = runtime·rfork_thread(flags, stk, m, g, fn)) < 0) {
runtime·printf("runtime: failed to create new OS thread (have %d already; errno=%d)\n", runtime·mcount() - 1, -ret);
runtime·printf("runtime: is kern.rthreads disabled?\n");
runtime·throw("runtime.newosproc");
}
}
void
runtime·osinit(void)
{
}
void
runtime·goenvs(void)
{
runtime·goenvs_unix();
}
// Called to initialize a new m (including the bootstrap m).
void
runtime·minit(void)
{
// Initialize signal handling
m->gsignal = runtime·malg(32*1024);
runtime·signalstack(m->gsignal->stackguard - StackGuard, 32*1024);
}
void
runtime·sigpanic(void)
{
switch(g->sig) {
case SIGBUS:
if(g->sigcode0 == BUS_ADRERR && g->sigcode1 < 0x1000)
runtime·panicstring("invalid memory address or nil pointer dereference");
runtime·printf("unexpected fault address %p\n", g->sigcode1);
runtime·throw("fault");
case SIGSEGV:
if((g->sigcode0 == 0 || g->sigcode0 == SEGV_MAPERR || g->sigcode0 == SEGV_ACCERR) && g->sigcode1 < 0x1000)
runtime·panicstring("invalid memory address or nil pointer dereference");
runtime·printf("unexpected fault address %p\n", g->sigcode1);
runtime·throw("fault");
case SIGFPE:
switch(g->sigcode0) {
case FPE_INTDIV:
runtime·panicstring("integer divide by zero");
case FPE_INTOVF:
runtime·panicstring("integer overflow");
}
runtime·panicstring("floating point error");
}
runtime·panicstring(runtime·sigtab[g->sig].name);
}
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