void
erts_proc_safelock(Process *a_proc,
ErtsProcLocks a_have_locks,
ErtsProcLocks a_need_locks,
Process *b_proc,
ErtsProcLocks b_have_locks,
ErtsProcLocks b_need_locks)
{
proc_safelock(erts_get_scheduler_id() != 0,
a_proc,
a_have_locks,
a_need_locks,
b_proc,
b_have_locks,
b_need_locks);
}
/*
** Schedule async_invoke on a worker thread
** NOTE will be syncrounous when threads are unsupported
** return values:
** 0 completed
** -1 error
** N handle value
** arguments:
** ix driver index
** key pointer to secedule queue (NULL means round robin)
** async_invoke function to run in thread
** async_data data to pass to invoke function
** async_free function for relase async_data in case of failure
*/
long driver_async(ErlDrvPort ix, unsigned int* key,
void (*async_invoke)(void*), void* async_data,
void (*async_free)(void*))
{
ErtsAsync* a;
Port* prt;
long id;
unsigned int qix;
#if ERTS_USE_ASYNC_READY_Q
Uint sched_id;
ERTS_MSACC_PUSH_STATE();
sched_id = erts_get_scheduler_id();
if (!sched_id)
sched_id = 1;
#else
ERTS_MSACC_PUSH_STATE();
#endif
prt = erts_drvport2port(ix);
if (prt == ERTS_INVALID_ERL_DRV_PORT)
return -1;
ERTS_SMP_LC_ASSERT(erts_lc_is_port_locked(prt));
a = (ErtsAsync*) erts_alloc(ERTS_ALC_T_ASYNC, sizeof(ErtsAsync));
#if ERTS_USE_ASYNC_READY_Q
a->sched_id = sched_id;
#endif
a->hndl = (DE_Handle*)prt->drv_ptr->handle;
a->port = prt->common.id;
a->pdl = NULL;
a->async_data = async_data;
a->async_invoke = async_invoke;
a->async_free = async_free;
if (!async)
id = 0;
else {
do {
id = erts_atomic_inc_read_nob(&async->init.data.id);
} while (id == 0);
if (id < 0)
id *= -1;
ASSERT(id > 0);
}
a->async_id = id;
if (key == NULL) {
qix = (erts_async_max_threads > 0)
? (id % erts_async_max_threads) : 0;
}
else {
qix = (erts_async_max_threads > 0) ?
(*key % erts_async_max_threads) : 0;
*key = qix;
}
#ifdef USE_THREADS
if (erts_async_max_threads > 0) {
if (prt->port_data_lock) {
driver_pdl_inc_refc(prt->port_data_lock);
a->pdl = prt->port_data_lock;
}
async_add(a, async_q(qix));
return id;
}
#endif
ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_PORT);
(*a->async_invoke)(a->async_data);
ERTS_MSACC_POP_STATE();
if (async_ready(prt, a->async_data)) {
if (a->async_free != NULL) {
ERTS_MSACC_SET_STATE_CACHED(ERTS_MSACC_STATE_PORT);
(*a->async_free)(a->async_data);
ERTS_MSACC_POP_STATE();
}
}
erts_free(ERTS_ALC_T_ASYNC, (void *) a);
return id;
}
Process *
erts_pid2proc_opt(Process *c_p,
ErtsProcLocks c_p_have_locks,
Eterm pid,
ErtsProcLocks pid_need_locks,
int flags)
{
Process *dec_refc_proc = NULL;
int need_ptl;
ErtsProcLocks need_locks;
Uint pix;
Process *proc;
#if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_ENABLE_LOCK_COUNT)
ErtsProcLocks lcnt_locks;
#endif
#ifdef ERTS_ENABLE_LOCK_CHECK
if (c_p) {
ErtsProcLocks might_unlock = c_p_have_locks & pid_need_locks;
if (might_unlock)
erts_proc_lc_might_unlock(c_p, might_unlock);
}
#endif
if (is_not_internal_pid(pid))
return NULL;
pix = internal_pid_index(pid);
ERTS_LC_ASSERT((pid_need_locks & ERTS_PROC_LOCKS_ALL) == pid_need_locks);
need_locks = pid_need_locks;
if (c_p && c_p->id == pid) {
ASSERT(c_p->id != ERTS_INVALID_PID);
ASSERT(c_p == erts_pix2proc(pix));
if (!(flags & ERTS_P2P_FLG_ALLOW_OTHER_X)
&& ERTS_PROC_IS_EXITING(c_p))
return NULL;
need_locks &= ~c_p_have_locks;
if (!need_locks) {
if (flags & ERTS_P2P_FLG_SMP_INC_REFC)
erts_smp_proc_inc_refc(c_p);
return c_p;
}
}
need_ptl = !erts_get_scheduler_id();
if (need_ptl)
erts_smp_rwmtx_rwlock(&erts_proc_tab_rwmtx);
proc = (Process *) erts_smp_atomic_read_ddrb(&erts_proc.tab[pix]);
if (proc) {
if (proc->id != pid)
proc = NULL;
else if (!need_locks) {
if (flags & ERTS_P2P_FLG_SMP_INC_REFC)
erts_smp_proc_inc_refc(proc);
}
else {
int busy;
#if ERTS_PROC_LOCK_OWN_IMPL
#ifdef ERTS_ENABLE_LOCK_COUNT
lcnt_locks = need_locks;
if (!(flags & ERTS_P2P_FLG_TRY_LOCK)) {
erts_lcnt_proc_lock(&proc->lock, need_locks);
}
#endif
#ifdef ERTS_ENABLE_LOCK_CHECK
/* Make sure erts_pid2proc_safelock() is enough to handle
a potential lock order violation situation... */
busy = erts_proc_lc_trylock_force_busy(proc, need_locks);
if (!busy)
#endif
#endif /* ERTS_PROC_LOCK_OWN_IMPL */
{
/* Try a quick trylock to grab all the locks we need. */
busy = (int) erts_smp_proc_raw_trylock__(proc, need_locks);
#if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_ENABLE_LOCK_CHECK)
erts_proc_lc_trylock(proc, need_locks, !busy);
#endif
#ifdef ERTS_PROC_LOCK_DEBUG
if (!busy)
erts_proc_lock_op_debug(proc, need_locks, 1);
#endif
}
#if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_ENABLE_LOCK_COUNT)
if (flags & ERTS_P2P_FLG_TRY_LOCK)
erts_lcnt_proc_trylock(&proc->lock, need_locks,
busy ? EBUSY : 0);
#endif
if (!busy) {
if (flags & ERTS_P2P_FLG_SMP_INC_REFC)
erts_smp_proc_inc_refc(proc);
#if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_ENABLE_LOCK_COUNT)
/* all is great */
if (!(flags & ERTS_P2P_FLG_TRY_LOCK))
erts_lcnt_proc_lock_post_x(&proc->lock, lcnt_locks,
__FILE__, __LINE__);
#endif
}
else {
if (flags & ERTS_P2P_FLG_TRY_LOCK)
proc = ERTS_PROC_LOCK_BUSY;
else {
if (flags & ERTS_P2P_FLG_SMP_INC_REFC)
erts_smp_proc_inc_refc(proc);
#if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_ENABLE_LOCK_COUNT)
erts_lcnt_proc_lock_unaquire(&proc->lock, lcnt_locks);
#endif
if (need_ptl) {
erts_smp_proc_inc_refc(proc);
dec_refc_proc = proc;
erts_smp_rwmtx_rwunlock(&erts_proc_tab_rwmtx);
need_ptl = 0;
}
proc_safelock(!need_ptl,
c_p,
c_p_have_locks,
c_p_have_locks,
proc,
0,
need_locks);
}
}
}
}
if (need_ptl)
erts_smp_rwmtx_rwunlock(&erts_proc_tab_rwmtx);
if (need_locks
&& proc
&& proc != ERTS_PROC_LOCK_BUSY
&& (!(flags & ERTS_P2P_FLG_ALLOW_OTHER_X)
? ERTS_PROC_IS_EXITING(proc)
: (proc
!= (Process *) erts_smp_atomic_read_nob(&erts_proc.tab[pix])))) {
erts_smp_proc_unlock(proc, need_locks);
if (flags & ERTS_P2P_FLG_SMP_INC_REFC)
dec_refc_proc = proc;
proc = NULL;
}
if (dec_refc_proc)
erts_smp_proc_dec_refc(dec_refc_proc);
#if ERTS_PROC_LOCK_OWN_IMPL && defined(ERTS_PROC_LOCK_DEBUG)
ERTS_LC_ASSERT(!proc
|| proc == ERTS_PROC_LOCK_BUSY
|| (pid_need_locks ==
(ERTS_PROC_LOCK_FLGS_READ_(&proc->lock)
& pid_need_locks)));
#endif
return proc;
}
