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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"
extern SigTab runtime·sigtab[];
extern int32 runtime·sys_umtx_op(uint32*, int32, uint32, void*, void*);
// FreeBSD's umtx_op syscall is effectively the same as Linux's futex, and
// thus the code is largely similar. See linux/thread.c for comments.
static void
umtx_wait(uint32 *addr, uint32 val)
{
int32 ret;
ret = runtime·sys_umtx_op(addr, UMTX_OP_WAIT, val, nil, nil);
if(ret >= 0 || ret == -EINTR)
return;
runtime·printf("umtx_wait addr=%p val=%d ret=%d\n", addr, val, ret);
*(int32*)0x1005 = 0x1005;
}
static void
umtx_wake(uint32 *addr)
{
int32 ret;
ret = runtime·sys_umtx_op(addr, UMTX_OP_WAKE, 1, nil, nil);
if(ret >= 0)
return;
runtime·printf("umtx_wake addr=%p ret=%d\n", addr, ret);
*(int32*)0x1006 = 0x1006;
}
// See linux/thread.c for comments about the algorithm.
static void
umtx_lock(Lock *l)
{
uint32 v;
again:
v = l->key;
if((v&1) == 0){
if(runtime·cas(&l->key, v, v|1))
return;
goto again;
}
if(!runtime·cas(&l->key, v, v+2))
goto again;
umtx_wait(&l->key, v+2);
for(;;){
v = l->key;
if(v < 2)
runtime·throw("bad lock key");
if(runtime·cas(&l->key, v, v-2))
break;
}
goto again;
}
static void
umtx_unlock(Lock *l)
{
uint32 v;
again:
v = l->key;
if((v&1) == 0)
runtime·throw("unlock of unlocked lock");
if(!runtime·cas(&l->key, v, v&~1))
goto again;
if(v&~1)
umtx_wake(&l->key);
}
void
runtime·lock(Lock *l)
{
if(m->locks < 0)
runtime·throw("lock count");
m->locks++;
umtx_lock(l);
}
void
runtime·unlock(Lock *l)
{
m->locks--;
if(m->locks < 0)
runtime·throw("lock count");
umtx_unlock(l);
}
void
runtime·destroylock(Lock*)
{
}
// Event notifications.
void
runtime·noteclear(Note *n)
{
n->lock.key = 0;
umtx_lock(&n->lock);
}
void
runtime·notesleep(Note *n)
{
umtx_lock(&n->lock);
umtx_unlock(&n->lock);
}
void
runtime·notewakeup(Note *n)
{
umtx_unlock(&n->lock);
}
void runtime·thr_start(void*);
void
runtime·newosproc(M *m, G *g, void *stk, void (*fn)(void))
{
ThrParam param;
USED(fn); // thr_start assumes fn == mstart
USED(g); // thr_start assumes g == m->g0
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);
}
runtime·memclr((byte*)¶m, sizeof param);
param.start_func = runtime·thr_start;
param.arg = m;
param.stack_base = (int8*)g->stackbase;
param.stack_size = (byte*)stk - (byte*)g->stackbase;
param.child_tid = (intptr*)&m->procid;
param.parent_tid = nil;
param.tls_base = (int8*)&m->tls[0];
param.tls_size = sizeof m->tls;
m->tls[0] = m->id; // so 386 asm can find it
runtime·thr_new(¶m, sizeof param);
}
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, 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);
}
|
