diff options
Diffstat (limited to 'erts/emulator/beam/msg_instrs.tab')
| -rw-r--r-- | erts/emulator/beam/msg_instrs.tab | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/erts/emulator/beam/msg_instrs.tab b/erts/emulator/beam/msg_instrs.tab new file mode 100644 index 0000000000..509143268b --- /dev/null +++ b/erts/emulator/beam/msg_instrs.tab @@ -0,0 +1,382 @@ +// -*- c -*- +// +// %CopyrightBegin% +// +// Copyright Ericsson AB 2017. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// +// %CopyrightEnd% +// + +// /* +// * Skeleton for receive statement: +// * +// * recv_mark L1 Optional +// * call make_ref/monitor Optional +// * ... +// * recv_set L1 Optional +// * L1: <-------------------+ +// * <-----------+ | +// * | | +// * loop_rec L2 ------+---+ | +// * ... | | | +// * remove_message | | | +// * jump L3 | | | +// * ... | | | +// * loop_rec_end L1 --+ | | +// * L2: <---------------+ | +// * wait L1 -------------------+ or wait_timeout +// * timeout +// * +// * L3: Code after receive... +// * +// */ + +recv_mark(Dest) { + /* + * Save the current position in message buffer and the + * the label for the loop_rec/2 instruction for the + * the receive statement. + */ + c_p->msg.mark = (BeamInstr *) $Dest; + c_p->msg.saved_last = c_p->msg.last; +} + +i_recv_set() { + /* + * If the mark is valid (points to the loop_rec/2 + * instruction that follows), we know that the saved + * position points to the first message that could + * possibly be matched out. + * + * If the mark is invalid, we do nothing, meaning that + * we will look through all messages in the message queue. + */ + if (c_p->msg.mark == (BeamInstr *) ($NEXT_INSTRUCTION)) { + c_p->msg.save = c_p->msg.saved_last; + } + /* Fall through to the loop_rec/2 instruction */ +} + +i_loop_rec(Dest) { + //| -no_prefetch + + /* + * Pick up the next message and place it in x(0). + * If no message, jump to a wait or wait_timeout instruction. + */ + + ErtsMessage* msgp; + + /* + * We need to disable GC while matching messages + * in the queue. This since messages with data outside + * the heap will be corrupted by a GC. + */ + ASSERT(!(c_p->flags & F_DELAY_GC)); + c_p->flags |= F_DELAY_GC; + +loop_rec__: + + PROCESS_MAIN_CHK_LOCKS(c_p); + + msgp = PEEK_MESSAGE(c_p); + + if (!msgp) { + erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + /* Make sure messages wont pass exit signals... */ + if (ERTS_PROC_PENDING_EXIT(c_p)) { + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + SWAPOUT; + c_p->flags &= ~F_DELAY_GC; + c_p->arity = 0; + goto do_schedule; /* Will be rescheduled for exit */ + } + ERTS_MSGQ_MV_INQ2PRIVQ(c_p); + msgp = PEEK_MESSAGE(c_p); + if (msgp) { + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + } else { + c_p->flags &= ~F_DELAY_GC; + SET_I((BeamInstr *) $Dest); + Goto(*I); /* Jump to a wait or wait_timeout instruction */ + } + } + if (is_non_value(ERL_MESSAGE_TERM(msgp))) { + SWAPOUT; /* erts_decode_dist_message() may write to heap... */ + if (!erts_decode_dist_message(c_p, ERTS_PROC_LOCK_MAIN, msgp, 0)) { + /* + * A corrupt distribution message that we weren't able to decode; + * remove it... + */ + /* No swapin should be needed */ + ASSERT(HTOP == c_p->htop && E == c_p->stop); + /* TODO: Add DTrace probe for this bad message situation? */ + UNLINK_MESSAGE(c_p, msgp); + msgp->next = NULL; + erts_cleanup_messages(msgp); + goto loop_rec__; + } + SWAPIN; + } + r(0) = ERL_MESSAGE_TERM(msgp); +} + +remove_message() { + //| -no_prefetch + + /* + * Remove a (matched) message from the message queue. + */ + + ErtsMessage* msgp; + PROCESS_MAIN_CHK_LOCKS(c_p); + + ERTS_CHK_MBUF_SZ(c_p); + + msgp = PEEK_MESSAGE(c_p); + + if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)) { + save_calls(c_p, &exp_receive); + } + if (ERL_MESSAGE_TOKEN(msgp) == NIL) { +#ifdef USE_VM_PROBES + if (DT_UTAG(c_p) != NIL) { + if (DT_UTAG_FLAGS(c_p) & DT_UTAG_PERMANENT) { + SEQ_TRACE_TOKEN(c_p) = am_have_dt_utag; + } else { + DT_UTAG(c_p) = NIL; + SEQ_TRACE_TOKEN(c_p) = NIL; + } + } else { +#endif + SEQ_TRACE_TOKEN(c_p) = NIL; +#ifdef USE_VM_PROBES + } + DT_UTAG_FLAGS(c_p) &= ~DT_UTAG_SPREADING; +#endif + } else if (ERL_MESSAGE_TOKEN(msgp) != am_undefined) { + Eterm msg; + SEQ_TRACE_TOKEN(c_p) = ERL_MESSAGE_TOKEN(msgp); +#ifdef USE_VM_PROBES + if (ERL_MESSAGE_TOKEN(msgp) == am_have_dt_utag) { + if (DT_UTAG(c_p) == NIL) { + DT_UTAG(c_p) = ERL_MESSAGE_DT_UTAG(msgp); + } + DT_UTAG_FLAGS(c_p) |= DT_UTAG_SPREADING; + } else { +#endif + ASSERT(is_tuple(SEQ_TRACE_TOKEN(c_p))); + ASSERT(SEQ_TRACE_TOKEN_ARITY(c_p) == 5); + ASSERT(is_small(SEQ_TRACE_TOKEN_SERIAL(c_p))); + ASSERT(is_small(SEQ_TRACE_TOKEN_LASTCNT(c_p))); + ASSERT(is_small(SEQ_TRACE_TOKEN_FLAGS(c_p))); + ASSERT(is_pid(SEQ_TRACE_TOKEN_SENDER(c_p))); + c_p->seq_trace_lastcnt = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p)); + if (c_p->seq_trace_clock < unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p))) { + c_p->seq_trace_clock = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p)); + } + msg = ERL_MESSAGE_TERM(msgp); + seq_trace_output(SEQ_TRACE_TOKEN(c_p), msg, SEQ_TRACE_RECEIVE, + c_p->common.id, c_p); +#ifdef USE_VM_PROBES + } +#endif + } +#ifdef USE_VM_PROBES + if (DTRACE_ENABLED(message_receive)) { + Eterm token2 = NIL; + DTRACE_CHARBUF(receiver_name, DTRACE_TERM_BUF_SIZE); + Sint tok_label = 0; + Sint tok_lastcnt = 0; + Sint tok_serial = 0; + + dtrace_proc_str(c_p, receiver_name); + token2 = SEQ_TRACE_TOKEN(c_p); + if (have_seqtrace(token2)) { + tok_label = signed_val(SEQ_TRACE_T_LABEL(token2)); + tok_lastcnt = signed_val(SEQ_TRACE_T_LASTCNT(token2)); + tok_serial = signed_val(SEQ_TRACE_T_SERIAL(token2)); + } + DTRACE6(message_receive, + receiver_name, size_object(ERL_MESSAGE_TERM(msgp)), + c_p->msg.len - 1, tok_label, tok_lastcnt, tok_serial); + } +#endif + UNLINK_MESSAGE(c_p, msgp); + JOIN_MESSAGE(c_p); + CANCEL_TIMER(c_p); + + erts_save_message_in_proc(c_p, msgp); + c_p->flags &= ~F_DELAY_GC; + + if (ERTS_IS_GC_DESIRED_INTERNAL(c_p, HTOP, E)) { + /* + * We want to GC soon but we leave a few + * reductions giving the message some time + * to turn into garbage. + */ + ERTS_VBUMP_LEAVE_REDS_INTERNAL(c_p, 5, FCALLS); + } + + ERTS_DBG_CHK_REDS(c_p, FCALLS); + ERTS_CHK_MBUF_SZ(c_p); + + ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p); + PROCESS_MAIN_CHK_LOCKS(c_p); +} + +loop_rec_end(Dest) { + //| -no_next + /* + * Advance the save pointer to the next message (the current + * message didn't match), then jump to the loop_rec instruction. + */ + + ASSERT(c_p->flags & F_DELAY_GC); + + SET_I((BeamInstr *) $Dest); + SAVE_MESSAGE(c_p); + if (FCALLS > 0 || FCALLS > neg_o_reds) { + FCALLS--; + goto loop_rec__; + } + + c_p->flags &= ~F_DELAY_GC; + c_p->i = I; + SWAPOUT; + c_p->arity = 0; + c_p->current = NULL; + goto do_schedule; +} + +timeout_locked() { + /* + * A timeout has occurred. Reset the save pointer so that the next + * receive statement will examine the first message first. + */ + + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + $timeout(); +} + +timeout() { + if (IS_TRACED_FL(c_p, F_TRACE_RECEIVE)) { + trace_receive(c_p, am_clock_service, am_timeout, NULL); + } + if (ERTS_PROC_GET_SAVED_CALLS_BUF(c_p)) { + save_calls(c_p, &exp_timeout); + } + c_p->flags &= ~F_TIMO; + JOIN_MESSAGE(c_p); +} + +TIMEOUT_VALUE() { + c_p->freason = EXC_TIMEOUT_VALUE; + goto find_func_info; +} + +i_wait_error_locked() { + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + $TIMEOUT_VALUE(); +} + +i_wait_error() { + $TIMEOUT_VALUE(); +} + +wait_timeout_unlocked_int := wait.lock.int.execute; +wait_timeout_locked_int := wait.int.execute; + +wait_timeout_unlocked := wait.lock.src.execute; +wait_timeout_locked := wait.src.execute; + +wait_unlocked := wait.lock.execute; +wait_locked := wait.unlocked.execute; + +wait.lock() { + erts_proc_lock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); +} + +wait.unlocked() { +} + +wait.int(Int) { + /* + * If we have already set the timer, we must NOT set it again. Therefore, + * we must test the F_INSLPQUEUE flag as well as the F_TIMO flag. + */ + if ((c_p->flags & (F_INSLPQUEUE | F_TIMO)) == 0) { + BeamInstr** pi = (BeamInstr **) c_p->def_arg_reg; + *pi = $NEXT_INSTRUCTION; + erts_set_proc_timer_uword(c_p, $Int); + } +} + +wait.src(Src) { + /* + * If we have already set the timer, we must NOT set it again. Therefore, + * we must test the F_INSLPQUEUE flag as well as the F_TIMO flag. + */ + if ((c_p->flags & (F_INSLPQUEUE | F_TIMO)) == 0) { + Eterm timeout_value = $Src; + if (timeout_value == make_small(0)) { + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + $NEXT0(); + } else if (timeout_value == am_infinity) { + c_p->flags |= F_TIMO; + } else { + int tres = erts_set_proc_timer_term(c_p, timeout_value); + if (tres == 0) { + /* + * The timer routiner will set c_p->i to the value in + * c_p->def_arg_reg[0]. Note that it is safe to use this + * location because there are no living x registers in + * a receive statement. + */ + BeamInstr** pi = (BeamInstr**) c_p->def_arg_reg; + *pi = $NEXT_INSTRUCTION; + } else { /* Wrong time */ + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + c_p->freason = EXC_TIMEOUT_VALUE; + goto find_func_info; + } + } + } +} + +// +// Prepare to wait indefinitely for a new message to arrive +// (or the time set above if falling through from above). +// When a new message arrives, control will be transferred +// the loop_rec instruction (at label L1). In case of +// of timeout, control will be transferred to the timeout +// instruction following the wait_timeout instruction. +// + +wait.execute(JumpTarget) { + c_p->i = (BeamInstr *) $JumpTarget; /* L1 */ + SWAPOUT; + c_p->arity = 0; + + if (!ERTS_PTMR_IS_TIMED_OUT(c_p)) { + erts_atomic32_read_band_relb(&c_p->state, + ~ERTS_PSFLG_ACTIVE); + } + ASSERT(!ERTS_PROC_IS_EXITING(c_p)); + erts_proc_unlock(c_p, ERTS_PROC_LOCKS_MSG_RECEIVE); + c_p->current = NULL; + goto do_schedule; + //| -no_next +} |