From 3ee5343415d6ae0ce1ff1c2a2555051431a9315e Mon Sep 17 00:00:00 2001 From: Dmytro Lytovchenko Date: Wed, 25 May 2016 14:37:03 +0200 Subject: erts: Add port monitors * erlang:monitor/2 with port argument is added, erlang:demonitor, using port task API and avoiding locking; * port_info and process_info support for monitored ports (with named port monitors support); * Exit signals contain type 'process' or 'port'; * Propagation of port exit signals; * Self-cleaning when origin process dies with monitor on; * 8 test cases + testcase for port driver crashing; * Documentation for all of the above (monitor, demonitor, port_info and process_info) updated --- erts/emulator/beam/bif.c | 410 +++++++++++++++++++++++++++++++---------------- 1 file changed, 269 insertions(+), 141 deletions(-) (limited to 'erts/emulator/beam/bif.c') diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c index b18910e2c7..fc14061a44 100644 --- a/erts/emulator/beam/bif.c +++ b/erts/emulator/beam/bif.c @@ -282,20 +282,17 @@ res_no_proc: { } } -#define ERTS_DEMONITOR_FALSE 2 -#define ERTS_DEMONITOR_TRUE 1 -#define ERTS_DEMONITOR_BADARG 0 -#define ERTS_DEMONITOR_YIELD_TRUE -1 -#define ERTS_DEMONITOR_INTERNAL_ERROR -2 - -static int +/* This function is allowed to return range of values handled by demonitor/1-2 + * Namely: atoms true, false, yield, internal_error, badarg or THE_NON_VALUE + */ +static Eterm remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to) { ErtsDSigData dsd; ErtsMonitor *dmon; ErtsMonitor *mon; int code; - int res; + Eterm res = am_false; #ifndef ERTS_SMP int stale_mon = 0; #endif @@ -328,7 +325,7 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to) mon = erts_remove_monitor(&ERTS_P_MONITORS(c_p), ref); erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_LINK); - res = ERTS_DEMONITOR_TRUE; + res = am_true; break; case ERTS_DSIG_PREP_CONNECTED: @@ -352,7 +349,7 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to) * This is possible when smp support is enabled. * 'DOWN' message just arrived. */ - res = ERTS_DEMONITOR_TRUE; + res = am_true; } else { /* @@ -367,16 +364,13 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to) : mon->pid), ref, 0); - res = (code == ERTS_DSIG_SEND_YIELD - ? ERTS_DEMONITOR_YIELD_TRUE - : ERTS_DEMONITOR_TRUE); + res = (code == ERTS_DSIG_SEND_YIELD ? am_yield : am_true); erts_destroy_monitor(dmon); - } break; default: ASSERT(! "Invalid dsig prepare result"); - return ERTS_DEMONITOR_INTERNAL_ERROR; + return am_internal_error; } #ifndef ERTS_SMP @@ -404,27 +398,96 @@ remote_demonitor(Process *c_p, DistEntry *dep, Eterm ref, Eterm to) return res; } -static int demonitor(Process *c_p, Eterm ref, Eterm *multip) +static ERTS_INLINE void +demonitor_local_process(Process *c_p, Eterm ref, Eterm to, Eterm *res) +{ + Process *rp = erts_pid2proc_opt(c_p, + ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK, + to, + ERTS_PROC_LOCK_LINK, + ERTS_P2P_FLG_ALLOW_OTHER_X); + ErtsMonitor *mon = erts_remove_monitor(&ERTS_P_MONITORS(c_p), ref); + +#ifndef ERTS_SMP + ASSERT(mon); +#else + if (!mon) + *res = am_false; + else +#endif + { + *res = am_true; + erts_destroy_monitor(mon); + } + if (rp) { + ErtsMonitor *rmon; + rmon = erts_remove_monitor(&ERTS_P_MONITORS(rp), ref); + if (rp != c_p) + erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK); + if (rmon != NULL) + erts_destroy_monitor(rmon); + } + else { + ERTS_SMP_ASSERT_IS_NOT_EXITING(c_p); + } +} + +static ERTS_INLINE BIF_RETTYPE +demonitor_local_port(Process *origin, Eterm ref, Eterm target) { - ErtsMonitor *mon = NULL; /* The monitor entry to delete */ - Process *rp; /* Local target process */ - Eterm to = NIL; /* Monitor link traget */ - DistEntry *dep = NULL; /* Target's distribution entry */ - int deref_de = 0; - int res; - int unlock_link = 1; + BIF_RETTYPE res = am_false; + Port *port = erts_port_lookup_raw(target); + + if (!port) { + BIF_ERROR(origin, BADARG); + } + erts_smp_proc_unlock(origin, ERTS_PROC_LOCK_LINK); + + if (port) { + Eterm trap_ref; + switch (erts_port_demonitor(origin, ERTS_PORT_DEMONITOR_NORMAL, + port, ref, &trap_ref)) { + case ERTS_PORT_OP_DROPPED: + case ERTS_PORT_OP_BADARG: + break; + case ERTS_PORT_OP_SCHEDULED: + BIF_TRAP3(await_port_send_result_trap, origin, trap_ref, + am_busy_port, am_true); + /* the busy_port atom will never be returned, because it cannot be + * returned from erts_port_(de)monitor, but just in case if in future + * internal API changes - you may see this atom */ + default: + break; + } + } + else { + ERTS_SMP_ASSERT_IS_NOT_EXITING(origin); + } + BIF_RET(res); +} +/* Can return atom true, false, yield, internal_error, badarg or + * THE_NON_VALUE if error occured or trap has been set up + */ +static +BIF_RETTYPE demonitor(Process *c_p, Eterm ref, Eterm *multip) +{ + ErtsMonitor *mon = NULL; /* The monitor entry to delete */ + Eterm to = NIL; /* Monitor link traget */ + DistEntry *dep = NULL; /* Target's distribution entry */ + int deref_de = 0; + BIF_RETTYPE res = am_false; + int unlock_link = 1; erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_LINK); if (is_not_internal_ref(ref)) { - res = ERTS_DEMONITOR_BADARG; + res = am_badarg; goto done; /* Cannot be this monitor's ref */ } mon = erts_lookup_monitor(ERTS_P_MONITORS(c_p), ref); if (!mon) { - res = ERTS_DEMONITOR_FALSE; goto done; } @@ -432,70 +495,50 @@ static int demonitor(Process *c_p, Eterm ref, Eterm *multip) case MON_TIME_OFFSET: *multip = am_true; erts_demonitor_time_offset(ref); - res = ERTS_DEMONITOR_TRUE; + res = am_true; break; case MON_ORIGIN: to = mon->pid; *multip = am_false; if (is_atom(to)) { - /* Monitoring a name at node to */ - ASSERT(is_node_name_atom(to)); - dep = erts_sysname_to_connected_dist_entry(to); - ASSERT(dep != erts_this_dist_entry); - if (dep) - deref_de = 1; + /* Monitoring a name at node to */ + ASSERT(is_node_name_atom(to)); + dep = erts_sysname_to_connected_dist_entry(to); + ASSERT(dep != erts_this_dist_entry); + if (dep) + deref_de = 1; + } else if (is_port(to)) { + if (port_dist_entry(to) != erts_this_dist_entry) { + goto badarg; + } + res = demonitor_local_port(c_p, ref, to); + unlock_link = 0; + goto done; } else { - ASSERT(is_pid(to)); - dep = pid_dist_entry(to); + ASSERT(is_pid(to)); + dep = pid_dist_entry(to); } if (dep != erts_this_dist_entry) { - res = remote_demonitor(c_p, dep, ref, to); - /* remote_demonitor() unlocks link lock on c_p */ - unlock_link = 0; + res = remote_demonitor(c_p, dep, ref, to); + /* remote_demonitor() unlocks link lock on c_p */ + unlock_link = 0; } else { /* Local monitor */ - if (deref_de) { - deref_de = 0; - erts_deref_dist_entry(dep); - } - dep = NULL; - rp = erts_pid2proc_opt(c_p, - ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK, - to, - ERTS_PROC_LOCK_LINK, - ERTS_P2P_FLG_ALLOW_OTHER_X); - mon = erts_remove_monitor(&ERTS_P_MONITORS(c_p), ref); -#ifndef ERTS_SMP - ASSERT(mon); -#else - if (!mon) - res = ERTS_DEMONITOR_FALSE; - else -#endif - { - res = ERTS_DEMONITOR_TRUE; - erts_destroy_monitor(mon); - } - if (rp) { - ErtsMonitor *rmon; - rmon = erts_remove_monitor(&ERTS_P_MONITORS(rp), ref); - if (rp != c_p) - erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK); - if (rmon != NULL) - erts_destroy_monitor(rmon); - } - else { - ERTS_SMP_ASSERT_IS_NOT_EXITING(c_p); - } - + if (deref_de) { + deref_de = 0; + erts_deref_dist_entry(dep); + } + dep = NULL; + demonitor_local_process(c_p, ref, to, &res); } break; - default: - res = ERTS_DEMONITOR_BADARG; + default /* case */ : +badarg: + res = am_badarg; /* will be converted to error by caller */ *multip = am_false; break; } - done: +done: if (unlock_link) erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_LINK); @@ -506,21 +549,20 @@ static int demonitor(Process *c_p, Eterm ref, Eterm *multip) } ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN == erts_proc_lc_my_proc_locks(c_p)); - return res; + BIF_RET(res); } BIF_RETTYPE demonitor_1(BIF_ALIST_1) { Eterm multi; switch (demonitor(BIF_P, BIF_ARG_1, &multi)) { - case ERTS_DEMONITOR_FALSE: - case ERTS_DEMONITOR_TRUE: - BIF_RET(am_true); - case ERTS_DEMONITOR_YIELD_TRUE: - ERTS_BIF_YIELD_RETURN(BIF_P, am_true); - case ERTS_DEMONITOR_BADARG: - BIF_ERROR(BIF_P, BADARG); - case ERTS_DEMONITOR_INTERNAL_ERROR: + case am_false: + case am_true: BIF_RET(am_true); + case THE_NON_VALUE: BIF_RET(THE_NON_VALUE); + case am_yield: ERTS_BIF_YIELD_RETURN(BIF_P, am_true); + case am_badarg: BIF_ERROR(BIF_P, BADARG); + + case am_internal_error: default: ASSERT(! "demonitor(): internal error"); BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR); @@ -529,11 +571,11 @@ BIF_RETTYPE demonitor_1(BIF_ALIST_1) BIF_RETTYPE demonitor_2(BIF_ALIST_2) { - Eterm res = am_true; - Eterm multi = am_false; - int info = 0; - int flush = 0; - Eterm list = BIF_ARG_2; + BIF_RETTYPE res = am_true; + Eterm multi = am_false; + int info = 0; + int flush = 0; + Eterm list = BIF_ARG_2; while (is_list(list)) { Eterm* consp = list_val(list); @@ -554,24 +596,27 @@ BIF_RETTYPE demonitor_2(BIF_ALIST_2) goto badarg; switch (demonitor(BIF_P, BIF_ARG_1, &multi)) { - case ERTS_DEMONITOR_FALSE: + case THE_NON_VALUE: + /* If other error occured or trap has been set up - pass through */ + BIF_RET(THE_NON_VALUE); + case am_false: if (info) res = am_false; if (flush) { - flush_messages: +flush_messages: BIF_TRAP3(flush_monitor_messages_trap, BIF_P, BIF_ARG_1, multi, res); } - case ERTS_DEMONITOR_TRUE: + case am_true: if (multi == am_true && flush) goto flush_messages; BIF_RET(res); - case ERTS_DEMONITOR_YIELD_TRUE: + case am_yield: ERTS_BIF_YIELD_RETURN(BIF_P, am_true); - case ERTS_DEMONITOR_BADARG: - badarg: + case am_badarg: +badarg: BIF_ERROR(BIF_P, BADARG); - case ERTS_DEMONITOR_INTERNAL_ERROR: + case am_internal_error: default: ASSERT(! "demonitor(): internal error"); BIF_ERROR(BIF_P, EXC_INTERNAL_ERROR); @@ -615,14 +660,13 @@ erts_queue_monitor_message(Process *p, erts_queue_message(p, *p_locksp, msgp, tup, am_system); } -static BIF_RETTYPE +static Eterm local_pid_monitor(Process *p, Eterm target, Eterm mon_ref, int boolean) { - BIF_RETTYPE ret; - Process *rp; + Eterm ret = mon_ref; + Process *rp; ErtsProcLocks p_locks = ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK; - ERTS_BIF_PREP_RET(ret, mon_ref); if (target == p->common.id) { return ret; } @@ -658,40 +702,112 @@ local_pid_monitor(Process *p, Eterm target, Eterm mon_ref, int boolean) } static BIF_RETTYPE -local_name_monitor(Process *p, Eterm target_name) +local_port_monitor(Process *origin, Eterm target) { - BIF_RETTYPE ret; - Eterm mon_ref; - ErtsProcLocks p_locks = ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_LINK; - Process *rp; + BIF_RETTYPE ref = erts_make_ref(origin); + Port *port = erts_sig_lookup_port(origin, target); + ErtsProcLocks p_locks = ERTS_PROC_LOCK_MAIN; - mon_ref = erts_make_ref(p); - ERTS_BIF_PREP_RET(ret, mon_ref); - erts_smp_proc_lock(p, ERTS_PROC_LOCK_LINK); - rp = erts_whereis_process(p, p_locks, target_name, ERTS_PROC_LOCK_LINK, - ERTS_P2P_FLG_ALLOW_OTHER_X); - if (!rp) { - DeclareTmpHeap(lhp,3,p); + if (!port) { +res_no_proc: + /* Send the DOWN message immediately. Ref is made on the fly because + * caller has never seen it yet. */ + erts_queue_monitor_message(origin, &p_locks, ref, + am_port, target, am_noproc); + } + else { + switch (erts_port_monitor(origin, port, target, &ref)) { + case ERTS_PORT_OP_DROPPED: + case ERTS_PORT_OP_BADARG: + goto res_no_proc; + case ERTS_PORT_OP_SCHEDULED: + BIF_TRAP3(await_port_send_result_trap, origin, ref, + am_busy_port, ref); + /* the busy_port atom will never be returned, because it cannot be + * returned from erts_port_monitor, but just in case if in future + * internal API changes - you may see this atom */ + default: + break; + } + } + erts_smp_proc_unlock(origin, p_locks & ~ERTS_PROC_LOCK_MAIN); + BIF_RET(ref); +} + +/* Type = process | port :: atom(), 1st argument passed to erlang:monitor/2 + */ +static BIF_RETTYPE +local_name_monitor(Process *self, Eterm type, Eterm target_name) +{ + BIF_RETTYPE ret = erts_make_ref(self); + + ErtsProcLocks p_locks = ERTS_PROC_LOCK_MAIN | ERTS_PROC_LOCK_LINK; + Process *proc = NULL; + Port *port = NULL; + + erts_smp_proc_lock(self, ERTS_PROC_LOCK_LINK); + + erts_whereis_name(self, p_locks, target_name, + &proc, ERTS_PROC_LOCK_LINK, + ERTS_P2P_FLG_ALLOW_OTHER_X, + &port, 0); + + /* If the name is not registered, + * or if we asked for proc and got a port, + * or if we asked for port and got a proc, + * we just send the 'DOWN' message. + */ + if ((!proc && !port) || + (type == am_process && port) || + (type == am_port && proc)) { + DeclareTmpHeap(lhp,3,self); Eterm item; - UseTmpHeap(3,p); - erts_smp_proc_unlock(p, ERTS_PROC_LOCK_LINK); + UseTmpHeap(3,self); + + erts_smp_proc_unlock(self, ERTS_PROC_LOCK_LINK); p_locks &= ~ERTS_PROC_LOCK_LINK; + item = TUPLE2(lhp, target_name, erts_this_dist_entry->sysname); - erts_queue_monitor_message(p, &p_locks, - mon_ref, am_process, item, am_noproc); - UnUseTmpHeap(3,p); - } - else if (rp != p) { - erts_add_monitor(&ERTS_P_MONITORS(p), MON_ORIGIN, mon_ref, rp->common.id, - target_name); - erts_add_monitor(&ERTS_P_MONITORS(rp), MON_TARGET, mon_ref, p->common.id, - target_name); - erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_LINK); + erts_queue_monitor_message(self, &p_locks, + ret, + type, /* = process|port :: atom() */ + item, am_noproc); + UnUseTmpHeap(3,self); + } + else if (port) { + erts_smp_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN); + p_locks &= ~ERTS_PROC_LOCK_MAIN; + + switch (erts_port_monitor(self, port, target_name, &ret)) { + case ERTS_PORT_OP_DONE: + return ret; + case ERTS_PORT_OP_SCHEDULED: { /* Scheduled a signal */ + ASSERT(is_internal_ref(ret)); + BIF_TRAP3(await_port_send_result_trap, self, + ret, am_true, ret); + /* bif_trap returns */ + } break; + default: + goto badarg; + } + } + else if (proc != self) { + erts_add_monitor(&ERTS_P_MONITORS(self), MON_ORIGIN, ret, + proc->common.id, target_name); + erts_add_monitor(&ERTS_P_MONITORS(proc), MON_TARGET, ret, + self->common.id, target_name); + erts_smp_proc_unlock(proc, ERTS_PROC_LOCK_LINK); } - erts_smp_proc_unlock(p, p_locks & ~ERTS_PROC_LOCK_MAIN); - - return ret; + if (p_locks) { + erts_smp_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN); + } + BIF_RET(ret); +badarg: + if (p_locks) { + erts_smp_proc_unlock(self, p_locks & ~ERTS_PROC_LOCK_MAIN); + } + BIF_ERROR(self, BADARG); } static BIF_RETTYPE @@ -758,7 +874,7 @@ remote_monitor(Process *p, Eterm bifarg1, Eterm bifarg2, break; } - return ret; + BIF_RET(ret); } BIF_RETTYPE monitor_2(BIF_ALIST_2) @@ -772,8 +888,9 @@ BIF_RETTYPE monitor_2(BIF_ALIST_2) switch (BIF_ARG_1) { case am_time_offset: { Eterm ref; - if (BIF_ARG_2 != am_clock_service) - goto error; + if (BIF_ARG_2 != am_clock_service) { + goto badarg; + } ref = erts_make_ref(BIF_P); erts_smp_proc_lock(BIF_P, ERTS_PROC_LOCK_LINK); erts_add_monitor(&ERTS_P_MONITORS(BIF_P), MON_TIME_OFFSET, @@ -783,46 +900,57 @@ BIF_RETTYPE monitor_2(BIF_ALIST_2) BIF_RET(ref); } case am_process: + case am_port: break; default: - goto error; + goto badarg; } - if (is_internal_pid(target)) { - local_pid: - ret = local_pid_monitor(BIF_P, target, erts_make_ref(BIF_P), 0); - } else if (is_external_pid(target)) { + if (is_internal_pid(target) && BIF_ARG_1 == am_process) { +local_pid: + ret = local_pid_monitor(BIF_P, target, erts_make_ref(BIF_P), 0); + } else if (is_external_pid(target) && BIF_ARG_1 == am_process) { dep = external_pid_dist_entry(target); if (dep == erts_this_dist_entry) goto local_pid; ret = remote_monitor(BIF_P, BIF_ARG_1, BIF_ARG_2, dep, target, 0); + } else if (is_internal_port(target) && BIF_ARG_1 == am_port) { +local_port: + ret = local_port_monitor(BIF_P, target); + } else if (is_external_port(target) && BIF_ARG_1 == am_port) { + dep = external_port_dist_entry(target); + if (dep == erts_this_dist_entry) { + goto local_port; + } + goto badarg; /* No want remote port */ } else if (is_atom(target)) { - ret = local_name_monitor(BIF_P, target); + ret = local_name_monitor(BIF_P, BIF_ARG_1, target); } else if (is_tuple(target)) { Eterm *tp = tuple_val(target); Eterm remote_node; Eterm name; - if (arityval(*tp) != 2) - goto error; + if (arityval(*tp) != 2) { + goto badarg; + } remote_node = tp[2]; name = tp[1]; if (!is_atom(remote_node) || !is_atom(name)) { - goto error; + goto badarg; } if (!erts_is_alive && remote_node != am_Noname) { - goto error; /* Remote monitor from (this) undistributed node */ + goto badarg; /* Remote monitor from (this) undistributed node */ } dep = erts_sysname_to_connected_dist_entry(remote_node); if (dep == erts_this_dist_entry) { deref_de = 1; - ret = local_name_monitor(BIF_P, name); + ret = local_name_monitor(BIF_P, BIF_ARG_1, name); } else { if (dep) deref_de = 1; ret = remote_monitor(BIF_P, BIF_ARG_1, BIF_ARG_2, dep, name, 1); } } else { - error: +badarg: ERTS_BIF_PREP_ERROR(ret, BIF_P, BADARG); } if (deref_de) { -- cgit v1.2.3