static int
ms_wait(Process *c_p, Eterm etimeout, int busy)
{
ErtsSchedulerData *esdp = erts_proc_sched_data(c_p);
ErtsMonotonicTime time, timeout_time;
Sint64 ms;
if (!term_to_Sint64(etimeout, &ms))
return 0;
time = erts_get_monotonic_time(esdp);
if (ms < 0)
timeout_time = time;
else
timeout_time = time + ERTS_MSEC_TO_MONOTONIC(ms);
while (time < timeout_time) {
if (busy)
erts_thr_yield();
else {
ErtsMonotonicTime timeout = timeout_time - time;
#ifdef __WIN32__
Sleep((DWORD) ERTS_MONOTONIC_TO_MSEC(timeout));
#else
{
ErtsMonotonicTime to = ERTS_MONOTONIC_TO_USEC(timeout);
struct timeval tv;
tv.tv_sec = (long) to / (1000*1000);
tv.tv_usec = (long) to % (1000*1000);
select(0, NULL, NULL, NULL, &tv);
}
#endif
}
time = erts_get_monotonic_time(esdp);
}
return 1;
}
/*
* erts_proc_lock_failed() is called when erts_smp_proc_lock()
* wasn't able to lock all locks. We may need to transfer locks
* to waiters and wait for our turn on locks.
*
* Iff !ERTS_PROC_LOCK_ATOMIC_IMPL, the pix lock is locked on entry.
*
* This always returns with the pix lock unlocked.
*/
void
erts_proc_lock_failed(Process *p,
erts_pix_lock_t *pixlck,
ErtsProcLocks locks,
ErtsProcLocks old_lflgs)
{
int until_yield = ERTS_PROC_LOCK_SPIN_UNTIL_YIELD;
int thr_spin_count;
int spin_count;
ErtsProcLocks need_locks = locks;
ErtsProcLocks olflgs = old_lflgs;
if (erts_thr_get_main_status())
thr_spin_count = proc_lock_spin_count;
else
thr_spin_count = aux_thr_proc_lock_spin_count;
spin_count = thr_spin_count;
while (need_locks != 0) {
ErtsProcLocks can_grab;
can_grab = in_order_locks(olflgs, need_locks);
if (can_grab == 0) {
/* Someone already has the lowest-numbered lock we want. */
if (spin_count-- <= 0) {
/* Too many retries, give up and sleep for the lock. */
wait_for_locks(p, pixlck, locks, need_locks, olflgs);
return;
}
ERTS_SPIN_BODY;
if (--until_yield == 0) {
until_yield = ERTS_PROC_LOCK_SPIN_UNTIL_YIELD;
erts_thr_yield();
}
olflgs = ERTS_PROC_LOCK_FLGS_READ_(&p->lock);
}
else {
/* Try to grab all of the grabbable locks at once with cmpxchg. */
ErtsProcLocks grabbed = olflgs | can_grab;
ErtsProcLocks nflgs =
ERTS_PROC_LOCK_FLGS_CMPXCHG_ACQB_(&p->lock, grabbed, olflgs);
if (nflgs == olflgs) {
/* Success! We grabbed the 'can_grab' locks. */
olflgs = grabbed;
need_locks &= ~can_grab;
/* Since we made progress, reset the spin count. */
spin_count = thr_spin_count;
}
else {
/* Compare-and-exchange failed, try again. */
olflgs = nflgs;
}
}
}
/* Now we have all of the locks we wanted. */
#if !ERTS_PROC_LOCK_ATOMIC_IMPL
erts_pix_unlock(pixlck);
#endif
}
static BIF_RETTYPE
dirty_test(Process *c_p, Eterm type, Eterm arg1, Eterm arg2, UWord *I)
{
BIF_RETTYPE ret;
if (am_scheduler == arg1) {
ErtsSchedulerData *esdp;
if (arg2 != am_type)
goto badarg;
esdp = erts_proc_sched_data(c_p);
if (!esdp)
goto scheduler_type_error;
switch (esdp->type) {
case ERTS_SCHED_NORMAL:
ERTS_BIF_PREP_RET(ret, am_normal);
break;
case ERTS_SCHED_DIRTY_CPU:
ERTS_BIF_PREP_RET(ret, am_dirty_cpu);
break;
case ERTS_SCHED_DIRTY_IO:
ERTS_BIF_PREP_RET(ret, am_dirty_io);
break;
default:
scheduler_type_error:
ERTS_BIF_PREP_RET(ret, am_error);
break;
}
}
else if (am_error == arg1) {
switch (arg2) {
case am_notsup:
ERTS_BIF_PREP_ERROR(ret, c_p, EXC_NOTSUP);
break;
case am_undef:
ERTS_BIF_PREP_ERROR(ret, c_p, EXC_UNDEF);
break;
case am_badarith:
ERTS_BIF_PREP_ERROR(ret, c_p, EXC_BADARITH);
break;
case am_noproc:
ERTS_BIF_PREP_ERROR(ret, c_p, EXC_NOPROC);
break;
case am_system_limit:
ERTS_BIF_PREP_ERROR(ret, c_p, SYSTEM_LIMIT);
break;
case am_badarg:
default:
goto badarg;
}
}
else if (am_copy == arg1) {
int i;
Eterm res;
for (res = NIL, i = 0; i < 1000; i++) {
Eterm *hp, sz;
Eterm cpy;
/* We do not want this to be optimized,
but rather the oposite... */
sz = size_object(arg2);
hp = HAlloc(c_p, sz);
cpy = copy_struct(arg2, sz, &hp, &c_p->off_heap);
hp = HAlloc(c_p, 2);
res = CONS(hp, cpy, res);
}
ERTS_BIF_PREP_RET(ret, res);
}
else if (am_send == arg1) {
dirty_send_message(c_p, arg2, am_ok);
ERTS_BIF_PREP_RET(ret, am_ok);
}
else if (ERTS_IS_ATOM_STR("wait", arg1)) {
if (!ms_wait(c_p, arg2, type == am_dirty_cpu))
goto badarg;
ERTS_BIF_PREP_RET(ret, am_ok);
}
else if (ERTS_IS_ATOM_STR("reschedule", arg1)) {
/*
* Reschedule operation after decrement of two until we reach
* zero. Switch between dirty scheduler types when 'n' is
* evenly divided by 4. If the initial value wasn't evenly
* dividable by 2, throw badarg exception.
*/
Eterm next_type;
Sint n;
if (!term_to_Sint(arg2, &n) || n < 0)
goto badarg;
if (n == 0)
ERTS_BIF_PREP_RET(ret, am_ok);
else {
Eterm argv[3];
Eterm eint = erts_make_integer((Uint) (n - 2), c_p);
if (n % 4 != 0)
next_type = type;
else {
switch (type) {
case am_dirty_cpu: next_type = am_dirty_io; break;
case am_dirty_io: next_type = am_normal; break;
case am_normal: next_type = am_dirty_cpu; break;
default: goto badarg;
}
}
switch (next_type) {
case am_dirty_io:
argv[0] = arg1;
argv[1] = eint;
ret = erts_schedule_bif(c_p,
argv,
I,
erts_debug_dirty_io_2,
ERTS_SCHED_DIRTY_IO,
am_erts_debug,
am_dirty_io,
2);
break;
case am_dirty_cpu:
argv[0] = arg1;
argv[1] = eint;
ret = erts_schedule_bif(c_p,
argv,
I,
erts_debug_dirty_cpu_2,
ERTS_SCHED_DIRTY_CPU,
am_erts_debug,
am_dirty_cpu,
2);
break;
case am_normal:
argv[0] = am_normal;
argv[1] = arg1;
argv[2] = eint;
ret = erts_schedule_bif(c_p,
argv,
I,
erts_debug_dirty_3,
ERTS_SCHED_NORMAL,
am_erts_debug,
am_dirty,
3);
break;
default:
goto badarg;
}
}
}
else if (ERTS_IS_ATOM_STR("ready_wait6_done", arg1)) {
ERTS_DECL_AM(ready);
ERTS_DECL_AM(done);
dirty_send_message(c_p, arg2, AM_ready);
ms_wait(c_p, make_small(6000), 0);
dirty_send_message(c_p, arg2, AM_done);
ERTS_BIF_PREP_RET(ret, am_ok);
}
else if (ERTS_IS_ATOM_STR("alive_waitexiting", arg1)) {
Process *real_c_p = erts_proc_shadow2real(c_p);
Eterm *hp, *hp2;
Uint sz;
int i;
ErtsSchedulerData *esdp = erts_proc_sched_data(c_p);
int dirty_io = esdp->type == ERTS_SCHED_DIRTY_IO;
if (ERTS_PROC_IS_EXITING(real_c_p))
goto badarg;
dirty_send_message(c_p, arg2, am_alive);
/* Wait until dead */
while (!ERTS_PROC_IS_EXITING(real_c_p)) {
if (dirty_io)
ms_wait(c_p, make_small(100), 0);
else
erts_thr_yield();
}
ms_wait(c_p, make_small(1000), 0);
/* Should still be able to allocate memory */
hp = HAlloc(c_p, 3); /* Likely on heap */
sz = 10000;
hp2 = HAlloc(c_p, sz); /* Likely in heap fragment */
*hp2 = make_pos_bignum_header(sz);
for (i = 1; i < sz; i++)
hp2[i] = (Eterm) 4711;
ERTS_BIF_PREP_RET(ret, TUPLE2(hp, am_ok, make_big(hp2)));
}
else {
badarg:
ERTS_BIF_PREP_ERROR(ret, c_p, BADARG);
}
return ret;
}
