From 03abff77e4a0c116f816443434b1864fa8ee12ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?=
Date: Tue, 8 Mar 2011 08:15:55 +0100
Subject: Implement process_info(Pid, current_{location,stacktrace})
---
erts/doc/src/erlang.xml | 19 ++++-
erts/emulator/beam/atom.names | 2 +
erts/emulator/beam/erl_bif_info.c | 151 ++++++++++++++++++++++++++++-------
erts/emulator/test/process_SUITE.erl | 95 +++++++++++++++++++++-
4 files changed, 233 insertions(+), 34 deletions(-)
(limited to 'erts')
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index b7d775541f..b59fda7ef7 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -3809,11 +3809,26 @@ os_prompt%
catches in this process. This InfoTuple may be
changed or removed without prior notice.
- {current_function, {Module, Function, Args}}
+ {current_function, {Module, Function, Arity}}
-
-
Module, Function, Args is
+
Module, Function, Arity is
the current function call of the process.
+ {current_location, {Module, Function, Arity, Location}}
+ -
+
Module, Function, Arity is
+ the current function call of the process.
+ Location is a list of two-tuples that describes the
+ location in the source code.
+
+
+ {current_stacktrace, Stack}
+ -
+
Return the current call stack back-trace (stacktrace)
+ of the process. The stack has the same format as returned by
+ erlang:get_stacktrace/0.
+
+
{dictionary, Dictionary}
-
Dictionary is the dictionary of the process.
diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index 68d64fb7b0..e7308dbf43 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -156,6 +156,8 @@ atom cr
atom crlf
atom creation
atom current_function
+atom current_location
+atom current_stacktrace
atom data
atom debug_flags
atom delay_trap
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index 6a74596f76..e17325b64f 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -119,6 +119,10 @@ static char erts_system_version[] = ("Erlang " ERLANG_OTP_RELEASE
# define PERFMON_GETPCR _IOR('P', 2, unsigned long long)
#endif
+static Eterm
+current_function(Process* p, Process* rp, Eterm** hpp, int full_info);
+static Eterm current_stacktrace(Process* p, Process* rp, Eterm** hpp);
+
static Eterm
bld_bin_list(Uint **hpp, Uint *szp, ErlOffHeap* oh)
{
@@ -554,6 +558,8 @@ static Eterm pi_args[] = {
am_suspending,
am_min_heap_size,
am_min_bin_vheap_size,
+ am_current_location,
+ am_current_stacktrace,
#ifdef HYBRID
am_message_binary
#endif
@@ -602,8 +608,10 @@ pi_arg2ix(Eterm arg)
case am_suspending: return 26;
case am_min_heap_size: return 27;
case am_min_bin_vheap_size: return 28;
+ case am_current_location: return 29;
+ case am_current_stacktrace: return 30;
#ifdef HYBRID
- case am_message_binary: return 29;
+ case am_message_binary: return 31;
#endif
default: return -1;
}
@@ -1006,35 +1014,15 @@ process_info_aux(Process *BIF_P,
break;
case am_current_function:
- if (rp->current == NULL) {
- rp->current = find_function_from_pc(rp->i);
- }
- if (rp->current == NULL) {
- hp = HAlloc(BIF_P, 3);
- res = am_undefined;
- } else {
- BeamInstr* current;
-
- if (rp->current[0] == am_erlang &&
- rp->current[1] == am_process_info &&
- (rp->current[2] == 1 || rp->current[2] == 2) &&
- (current = find_function_from_pc(rp->cp)) != NULL) {
-
- /*
- * The current function is erlang:process_info/2,
- * which is not the answer that the application want.
- * We will use the function pointed into by rp->cp
- * instead.
- */
+ res = current_function(BIF_P, rp, &hp, 0);
+ break;
- rp->current = current;
- }
+ case am_current_location:
+ res = current_function(BIF_P, rp, &hp, 1);
+ break;
- hp = HAlloc(BIF_P, 3+4);
- res = TUPLE3(hp, rp->current[0],
- rp->current[1], make_small(rp->current[2]));
- hp += 4;
- }
+ case am_current_stacktrace:
+ res = current_stacktrace(BIF_P, rp, &hp);
break;
case am_initial_call:
@@ -1608,6 +1596,113 @@ process_info_aux(Process *BIF_P,
}
#undef MI_INC
+static Eterm
+current_function(Process* BIF_P, Process* rp, Eterm** hpp, int full_info)
+{
+ Eterm* hp;
+ Eterm res;
+ FunctionInfo fi;
+
+ if (rp->current == NULL) {
+ erts_lookup_function_info(&fi, rp->i, full_info);
+ rp->current = fi.current;
+ } else if (full_info) {
+ erts_lookup_function_info(&fi, rp->i, full_info);
+ if (fi.current == NULL) {
+ /* Use the current function without location info */
+ erts_set_current_function(&fi, rp->current);
+ }
+ }
+
+ if (BIF_P->id == rp->id) {
+ FunctionInfo fi2;
+
+ /*
+ * The current function is erlang:process_info/{1,2},
+ * which is not the answer that the application want.
+ * We will use the function pointed into by rp->cp
+ * instead if it can be looked up.
+ */
+ erts_lookup_function_info(&fi2, rp->cp, full_info);
+ if (fi2.current) {
+ fi = fi2;
+ rp->current = fi2.current;
+ }
+ }
+
+ /*
+ * Return the result.
+ */
+ if (rp->current == NULL) {
+ hp = HAlloc(BIF_P, 3);
+ res = am_undefined;
+ } else if (full_info) {
+ hp = HAlloc(BIF_P, 3+fi.needed);
+ hp = erts_build_mfa_item(&fi, hp, am_true, &res);
+ } else {
+ hp = HAlloc(BIF_P, 3+4);
+ res = TUPLE3(hp, rp->current[0],
+ rp->current[1], make_small(rp->current[2]));
+ hp += 4;
+ }
+ *hpp = hp;
+ return res;
+}
+
+static Eterm
+current_stacktrace(Process* p, Process* rp, Eterm** hpp)
+{
+ Uint sz;
+ struct StackTrace* s;
+ int depth;
+ FunctionInfo* stk;
+ FunctionInfo* stkp;
+ Uint heap_size;
+ int i;
+ Eterm* hp = *hpp;
+ Eterm mfa;
+ Eterm res = NIL;
+
+ depth = 8;
+ sz = offsetof(struct StackTrace, trace) + sizeof(BeamInstr *)*depth;
+ s = (struct StackTrace *) erts_alloc(ERTS_ALC_T_TMP, sz);
+ s->depth = 0;
+ if (rp->i) {
+ s->trace[s->depth++] = rp->i;
+ depth--;
+ }
+ if (depth > 0 && rp->cp != 0) {
+ s->trace[s->depth++] = rp->cp - 1;
+ depth--;
+ }
+ erts_save_stacktrace(rp, s, depth);
+
+ depth = s->depth;
+ stk = stkp = (FunctionInfo *) erts_alloc(ERTS_ALC_T_TMP,
+ depth*sizeof(FunctionInfo));
+ heap_size = 3;
+ for (i = 0; i < depth; i++) {
+ erts_lookup_function_info(stkp, s->trace[i], 1);
+ if (stkp->current) {
+ heap_size += stkp->needed + 2;
+ stkp++;
+ }
+ }
+
+ hp = HAlloc(p, heap_size);
+ while (stkp > stk) {
+ stkp--;
+ hp = erts_build_mfa_item(stkp, hp, am_true, &mfa);
+ res = CONS(hp, mfa, res);
+ hp += 2;
+ }
+
+ erts_free(ERTS_ALC_T_TMP, stk);
+ erts_free(ERTS_ALC_T_TMP, s);
+ *hpp = hp;
+ return res;
+}
+
#if defined(VALGRIND)
static int check_if_xml(void)
{
diff --git a/erts/emulator/test/process_SUITE.erl b/erts/emulator/test/process_SUITE.erl
index 5641489f5c..fdc55a4cc5 100644
--- a/erts/emulator/test/process_SUITE.erl
+++ b/erts/emulator/test/process_SUITE.erl
@@ -35,7 +35,7 @@
self_exit/1, normal_suicide_exit/1, abnormal_suicide_exit/1,
t_exit_2_catch/1, trap_exit_badarg/1, trap_exit_badarg_in_bif/1,
exit_and_timeout/1, exit_twice/1,
- t_process_info/1, process_info_other_msg/1,
+ t_process_info/1, process_info_other/1, process_info_other_msg/1,
process_info_other_dist_msg/1,
process_info_2_list/1, process_info_lock_reschedule/1,
process_info_lock_reschedule2/1,
@@ -64,7 +64,7 @@ suite() -> [{ct_hooks,[ts_install_cth]}].
all() ->
[spawn_with_binaries, t_exit_1, {group, t_exit_2},
trap_exit_badarg, trap_exit_badarg_in_bif,
- t_process_info, process_info_other_msg,
+ t_process_info, process_info_other, process_info_other_msg,
process_info_other_dist_msg, process_info_2_list,
process_info_lock_reschedule,
process_info_lock_reschedule2,
@@ -412,7 +412,7 @@ etwice_high(Low) ->
exit(Low, first),
exit(Low, second).
-%% Tests the process_info/1 BIF.
+%% Tests the process_info/2 BIF.
t_process_info(Config) when is_list(Config) ->
?line [] = process_info(self(), registered_name),
?line register(my_name, self()),
@@ -420,13 +420,100 @@ t_process_info(Config) when is_list(Config) ->
?line {status, running} = process_info(self(), status),
?line {min_heap_size, 233} = process_info(self(), min_heap_size),
?line {min_bin_vheap_size, 46368} = process_info(self(), min_bin_vheap_size),
- ?line {current_function, {?MODULE, t_process_info, 1}} =
+ ?line {current_function,{?MODULE,t_process_info,1}} =
process_info(self(), current_function),
+ ?line {current_function,{?MODULE,t_process_info,1}} =
+ apply(erlang, process_info, [self(),current_function]),
+
+ %% current_location and current_stacktrace
+ {Line1,Res1} = {?LINE,process_info(self(), current_location)},
+ verify_loc(Line1, Res1),
+ {Line2,Res2} = {?LINE,apply(erlang, process_info,
+ [self(),current_location])},
+ verify_loc(Line2, Res2),
+ pi_stacktrace([{?MODULE,t_process_info,1,?LINE}]),
+
?line Gleader = group_leader(),
?line {group_leader, Gleader} = process_info(self(), group_leader),
?line {'EXIT',{badarg,_Info}} = (catch process_info('not_a_pid')),
ok.
+pi_stacktrace(Expected0) ->
+ {Line,Res} = {?LINE,erlang:process_info(self(), current_stacktrace)},
+ {current_stacktrace,Stack} = Res,
+ Expected = [{?MODULE,pi_stacktrace,1,Line}|Expected0],
+ pi_stacktrace_1(Stack, Expected).
+
+pi_stacktrace_1([{M,F,A,Loc}|Stk], [{M,F,A,Line}|Exp]) ->
+ case Loc of
+ [] ->
+ %% No location info for some reason (+L, native code).
+ io:format("Missing location information for ~w:~w/~w",
+ [M,F,A]),
+ ok;
+ [_|_] ->
+ Line = proplists:get_value(line, Loc),
+ File = proplists:get_value(file, Loc),
+ File = ?MODULE_STRING ++ ".erl"
+ end,
+ pi_stacktrace_1(Stk, Exp);
+pi_stacktrace_1([_|_], []) -> ok.
+
+verify_loc(Line, {current_location,{?MODULE,t_process_info=F,1=A,Loc}}) ->
+ case Loc of
+ [] ->
+ %% No location info for some reason (+L, native code).
+ io:format("Missing location information for ~w:~w/~w",
+ [?MODULE,F,A]),
+ ok;
+ [_|_] ->
+ Line = proplists:get_value(line, Loc),
+ File = proplists:get_value(file, Loc),
+ File = ?MODULE_STRING ++ ".erl"
+ end.
+
+process_info_other(Config) when is_list(Config) ->
+ Self = self(),
+ Pid = spawn_link(fun() -> process_info_looper(Self) end),
+ receive after 1 -> ok end,
+ pio_current_location(10000, Pid, 0, 0),
+ pio_current_stacktrace().
+
+pio_current_location(0, _, Pi, Looper) ->
+ io:format("~w call(s) to erlang:process_info/2", [Pi]),
+ io:format("~w call(s) to ~w:process_info_looper/1", [Looper,?MODULE]);
+pio_current_location(N, Pid, Pi, Looper) ->
+ erlang:yield(),
+ {current_location,Where} = process_info(Pid, current_location),
+ case Where of
+ {erlang,process_info,2,[]} ->
+ pio_current_location(N-1, Pid, Pi+1, Looper);
+ {?MODULE,process_info_looper,1,Loc} when is_list(Loc) ->
+ pio_current_location(N-1, Pid, Pi, Looper+1)
+ end.
+
+pio_current_stacktrace() ->
+ L = [begin
+ {current_stacktrace,Stk} = process_info(P, current_stacktrace),
+ {P,Stk}
+ end || P <- processes()],
+ [erlang:garbage_collect(P) || {P,_} <- L],
+ erlang:garbage_collect(),
+ [verify_stacktrace(Stk) || {_,Stk} <- L],
+ ok.
+
+verify_stacktrace([{M,F,A,Loc}|T])
+ when is_atom(M),
+ is_atom(F),
+ is_integer(A),
+ is_list(Loc) ->
+ verify_stacktrace(T);
+verify_stacktrace([]) -> ok.
+
+process_info_looper(Parent) ->
+ process_info(Parent, current_location),
+ process_info_looper(Parent).
+
%% Tests the process_info/1 BIF on another process with messages.
process_info_other_msg(Config) when is_list(Config) ->
Self = self(),
--
cgit v1.2.3