From b001b56e061454f3175d9d9a99e2efb945a696b9 Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Tue, 4 Oct 2016 10:24:56 +0200 Subject: erts: Do tracer liveness check on current tracer This fixes a fault introduced in 19.0 where an invalid tracer would block setting of a new tracer on a process. --- erts/emulator/beam/erl_bif_trace.c | 10 +++++----- erts/emulator/test/trace_SUITE.erl | 32 ++++++++++++++++++++++++++++++-- 2 files changed, 35 insertions(+), 7 deletions(-) (limited to 'erts') diff --git a/erts/emulator/beam/erl_bif_trace.c b/erts/emulator/beam/erl_bif_trace.c index 66e5146da0..96275eb228 100644 --- a/erts/emulator/beam/erl_bif_trace.c +++ b/erts/emulator/beam/erl_bif_trace.c @@ -512,7 +512,7 @@ start_trace(Process *c_p, ErtsTracer tracer, && !ERTS_TRACER_COMPARE(ERTS_TRACER(port), tracer)) { /* This tracee is already being traced, and not by the * tracer to be */ - if (erts_is_tracer_enabled(tracer, common)) { + if (erts_is_tracer_enabled(ERTS_TRACER(port), common)) { /* The tracer is still in use */ return 1; } @@ -715,8 +715,8 @@ Eterm erts_internal_trace_3(BIF_ALIST_3) Process* tracee_p = erts_pix2proc(i); if (! tracee_p) continue; - start_trace(p, tracer, &tracee_p->common, on, mask); - matches++; + if (!start_trace(p, tracer, &tracee_p->common, on, mask)) + matches++; } } if (ports || mods) { @@ -730,8 +730,8 @@ Eterm erts_internal_trace_3(BIF_ALIST_3) state = erts_atomic32_read_nob(&tracee_port->state); if (state & ERTS_PORT_SFLGS_DEAD) continue; - start_trace(p, tracer, &tracee_port->common, on, mask); - matches++; + if (!start_trace(p, tracer, &tracee_port->common, on, mask)) + matches++; } } } diff --git a/erts/emulator/test/trace_SUITE.erl b/erts/emulator/test/trace_SUITE.erl index da6a6bdea4..f846b0f4b9 100644 --- a/erts/emulator/test/trace_SUITE.erl +++ b/erts/emulator/test/trace_SUITE.erl @@ -30,7 +30,7 @@ procs_trace/1, dist_procs_trace/1, procs_new_trace/1, suspend/1, mutual_suspend/1, suspend_exit/1, suspender_exit/1, suspend_system_limit/1, suspend_opts/1, suspend_waiting/1, - new_clear/1, existing_clear/1, + new_clear/1, existing_clear/1, tracer_die/1, set_on_spawn/1, set_on_first_spawn/1, cpu_timestamp/1, set_on_link/1, set_on_first_link/1, system_monitor_args/1, more_system_monitor_args/1, @@ -54,7 +54,7 @@ all() -> send_trace, procs_trace, dist_procs_trace, suspend, mutual_suspend, suspend_exit, suspender_exit, suspend_system_limit, suspend_opts, suspend_waiting, - new_clear, existing_clear, set_on_spawn, + new_clear, existing_clear, tracer_die, set_on_spawn, set_on_first_spawn, set_on_link, set_on_first_link, system_monitor_args, more_system_monitor_args, system_monitor_long_gc_1, @@ -1636,6 +1636,34 @@ existing_clear(Config) when is_list(Config) -> ok. +%% Test that erlang:trace/3 can be called on processes where the +%% tracer has died. OTP-13928 +tracer_die(Config) when is_list(Config) -> + Proc = spawn(fun receiver/0), + + Tracer = spawn(fun receiver/0), + timer:sleep(1), + N = erlang:trace(existing, true, [send, {tracer, Tracer}]), + {flags, [send]} = erlang:trace_info(Proc, flags), + {tracer, Tracer} = erlang:trace_info(Proc, tracer), + exit(Tracer, die), + + Tracer2 = spawn(fun receiver/0), + timer:sleep(1), + N = erlang:trace(existing, true, [send, {tracer, Tracer2}]), + {flags, [send]} = erlang:trace_info(Proc, flags), + {tracer, Tracer2} = erlang:trace_info(Proc, tracer), + exit(Tracer2, die), + + Tracer3 = spawn(fun receiver/0), + timer:sleep(1), + 1 = erlang:trace(Proc, true, [send, {tracer, Tracer3}]), + {flags, [send]} = erlang:trace_info(Proc, flags), + {tracer, Tracer3} = erlang:trace_info(Proc, tracer), + exit(Tracer3, die), + + ok. + %% Test that an invalid flag cause badarg bad_flag(Config) when is_list(Config) -> %% A bad flag could deadlock the SMP emulator in erts-5.5 -- cgit v1.2.3