From 0889c9860f5d07fc87db6bfc287b9a3ddc764aa1 Mon Sep 17 00:00:00 2001 From: Patrik Nyblom Date: Thu, 8 Mar 2012 16:05:16 +0100 Subject: Move dtrace erlang code and NIF into runtime_tools Also make dyntrace NIF's load in on_load instead of init/0 --- lib/runtime_tools/src/dyntrace.erl | 279 +++++++++++++++++++++++++++++++++++++ 1 file changed, 279 insertions(+) create mode 100644 lib/runtime_tools/src/dyntrace.erl (limited to 'lib/runtime_tools/src/dyntrace.erl') diff --git a/lib/runtime_tools/src/dyntrace.erl b/lib/runtime_tools/src/dyntrace.erl new file mode 100644 index 0000000000..20472a2be6 --- /dev/null +++ b/lib/runtime_tools/src/dyntrace.erl @@ -0,0 +1,279 @@ +-module(dyntrace). + +%%% @doc The Dynamic tracing interface module +%%% +%%% This Dynamic tracing interface module, with the corresponding NIFs, should +%%% work on any operating system platform where user-space DTrace/Systemtap +%%% (and in the future LttNG UST) probes are supported. +%%% +%%% Use the `dyntrace:init()' function to load the NIF shared library and +%%% to initialize library's private state. +%%% +%%% It is recommended that you use the `dyntrace:p()' function to add +%%% Dynamic trace probes to your Erlang code. This function can accept up to +%%% four integer arguments and four string arguments; the integer +%%% argument(s) must come before any string argument. For example: +%%% ``` +%%% 1> dyntrace:put_utag("GGOOOAAALL!!!!!"). +%%% true +%%% 2> dyntrace:init(). +%%% ok +%%% +%%% % % % If using dtrace, enable the Dynamic trace probe using the 'dtrace' +%%% % % % command. +%%% +%%% 3> dyntrace:p(7, 8, 9, "one", "four"). +%%% true +%%% ''' +%%% +%%% Output from the example D script `user-probe.d' looks like: +%%% ``` +%%% <0.34.0> GGOOOAAALL!!!!! 7 8 9 0 'one' 'four' '' '' +%%% ''' +%%% +%%% If the expected type of variable is not present, e.g. integer when +%%% integer() is expected, or an I/O list when iolist() is expected, +%%% then the driver will ignore the user's input and use a default +%%% value of 0 or NULL, respectively. + +-export([available/0, + user_trace_s1/1, % TODO: unify with pid & tag args like user_trace_i4s4 + p/0, p/1, p/2, p/3, p/4, p/5, p/6, p/7, p/8]). +-export([put_utag/1, get_utag/0, get_utag_data/0, spread_utag/1, restore_utag/1]). + +-export([scaff/0]). % Development only +-export([user_trace_i4s4/9]). % Know what you're doing! +-on_load(on_load/0). + +-type probe_arg() :: integer() | iolist(). +-type int_p_arg() :: integer() | iolist() | undef. + +%% The *_maybe() types use atom() instead of a stricter 'undef' +%% because user_trace_i4s4/9 is exposed to the outside world, and +%% because the driver will allow any atom to be used as a "not +%% present" indication, we'll allow any atom in the types. + +-type integer_maybe() :: integer() | atom(). +-type iolist_maybe() :: iolist() | atom(). + +on_load() -> + PrivDir = code:priv_dir(runtime_tools), + LibName = "dyntrace", + Lib = filename:join([PrivDir, "lib", LibName]), + Status = case erlang:load_nif(Lib, 0) of + ok -> ok; + {error, {load_failed, _}}=Error1 -> + ArchLibDir = + filename:join([PrivDir, "lib", + erlang:system_info(system_architecture)]), + Candidate = + filelib:wildcard(filename:join([ArchLibDir,LibName ++ "*" ])), + case Candidate of + [] -> Error1; + _ -> + ArchLib = filename:join([ArchLibDir, LibName]), + erlang:load_nif(ArchLib, 0) + end; + Error1 -> Error1 + end, + case Status of + ok -> ok; + {error, {E, Str}} -> + case erlang:system_info(dynamic_trace) of + none -> + ok; + _ -> + error_logger:error_msg("Unable to load dyntrace library. Failed with error:~n +\"~p, ~s\"~n" + "Dynamic tracing is enabled but the driver is not built correctly~n",[ + E,Str]), + Status + end + end. + +%%% +%%% NIF placeholders +%%% + +-spec available() -> true | false. + +available() -> + erlang:nif_error(nif_not_loaded). + +-spec user_trace_s1(iolist()) -> true | false | error | badarg. + +user_trace_s1(_Message) -> + erlang:nif_error(nif_not_loaded). + +-spec user_trace_i4s4(iolist(), + integer_maybe(), integer_maybe(), + integer_maybe(), integer_maybe(), + iolist_maybe(), iolist_maybe(), + iolist_maybe(), iolist_maybe()) -> + true | false | error | badarg. + +user_trace_i4s4(_, _, _, _, _, _, _, _, _) -> + erlang:nif_error(nif_not_loaded). + +%%% +%%% Erlang support functions +%%% + +-spec p() -> true | false | error | badarg. + +p() -> + user_trace_int(undef, undef, undef, undef, undef, undef, undef, undef). + +-spec p(probe_arg()) -> true | false | error | badarg. + +p(I1) when is_integer(I1) -> + user_trace_int(I1, undef, undef, undef, undef, undef, undef, undef); +p(S1) -> + user_trace_int(undef, undef, undef, undef, S1, undef, undef, undef). + +-spec p(probe_arg(), probe_arg()) -> true | false | error | badarg. + +p(I1, I2) when is_integer(I1), is_integer(I2) -> + user_trace_int(I1, I2, undef, undef, undef, undef, undef, undef); +p(I1, S1) when is_integer(I1) -> + user_trace_int(I1, undef, undef, undef, S1, undef, undef, undef); +p(S1, S2) -> + user_trace_int(undef, undef, undef, undef, S1, S2, undef, undef). + +-spec p(probe_arg(), probe_arg(), probe_arg()) -> true | false | error | badarg. + +p(I1, I2, I3) when is_integer(I1), is_integer(I2), is_integer(I3) -> + user_trace_int(I1, I2, I3, undef, undef, undef, undef, undef); +p(I1, I2, S1) when is_integer(I1), is_integer(I2) -> + user_trace_int(I1, I2, undef, undef, S1, undef, undef, undef); +p(I1, S1, S2) when is_integer(I1) -> + user_trace_int(I1, undef, undef, undef, S1, S2, undef, undef); +p(S1, S2, S3) -> + user_trace_int(undef, undef, undef, undef, S1, S2, S3, undef). + +-spec p(probe_arg(), probe_arg(), probe_arg(), probe_arg()) -> + true | false | error | badarg. + +p(I1, I2, I3, I4) when is_integer(I1), is_integer(I2), is_integer(I3), is_integer(I4) -> + user_trace_int(I1, I2, I3, I4, undef, undef, undef, undef); +p(I1, I2, I3, S1) when is_integer(I1), is_integer(I2), is_integer(I3) -> + user_trace_int(I1, I2, I3, undef, S1, undef, undef, undef); +p(I1, I2, S1, S2) when is_integer(I1), is_integer(I2) -> + user_trace_int(I1, I2, undef, undef, S1, S2, undef, undef); +p(I1, S1, S2, S3) when is_integer(I1) -> + user_trace_int(I1, undef, undef, undef, S1, S2, S3, undef); +p(S1, S2, S3, S4) -> + user_trace_int(undef, undef, undef, undef, S1, S2, S3, S4). + +-spec p(probe_arg(), probe_arg(), probe_arg(), probe_arg(), + probe_arg()) -> + true | false | error | badarg. + +p(I1, I2, I3, I4, S1) when is_integer(I1), is_integer(I2), is_integer(I3), is_integer(I4) -> + user_trace_int(I1, I2, I3, I4, S1, undef, undef, undef); +p(I1, I2, I3, S1, S2) when is_integer(I1), is_integer(I2), is_integer(I3) -> + user_trace_int(I1, I2, I3, undef, S1, S2, undef, undef); +p(I1, I2, S1, S2, S3) when is_integer(I1), is_integer(I2) -> + user_trace_int(I1, I2, undef, undef, S1, S2, S3, undef); +p(I1, S1, S2, S3, S4) when is_integer(I1) -> + user_trace_int(I1, undef, undef, undef, S1, S2, S3, S4). + +-spec p(probe_arg(), probe_arg(), probe_arg(), probe_arg(), + probe_arg(), probe_arg()) -> + true | false | error | badarg. + +p(I1, I2, I3, I4, S1, S2) when is_integer(I1), is_integer(I2), is_integer(I3), is_integer(I4) -> + user_trace_int(I1, I2, I3, I4, S1, S2, undef, undef); +p(I1, I2, I3, S1, S2, S3) when is_integer(I1), is_integer(I2), is_integer(I3) -> + user_trace_int(I1, I2, I3, undef, S1, S2, S3, undef); +p(I1, I2, S1, S2, S3, S4) when is_integer(I1), is_integer(I2) -> + user_trace_int(I1, I2, undef, undef, S1, S2, S3, S4). + +-spec p(probe_arg(), probe_arg(), probe_arg(), probe_arg(), + probe_arg(), probe_arg(), probe_arg()) -> + true | false | error | badarg. + +p(I1, I2, I3, I4, S1, S2, S3) when is_integer(I1), is_integer(I2), is_integer(I3), is_integer(I4) -> + user_trace_int(I1, I2, I3, I4, S1, S2, S3, undef); +p(I1, I2, I3, S1, S2, S3, S4) when is_integer(I1), is_integer(I2), is_integer(I3) -> + user_trace_int(I1, I2, I3, undef, S1, S2, S3, S4). + +-spec p(probe_arg(), probe_arg(), probe_arg(), probe_arg(), + probe_arg(), probe_arg(), probe_arg(), probe_arg()) -> + true | false | error | badarg. + +p(I1, I2, I3, I4, S1, S2, S3, S4) when is_integer(I1), is_integer(I2), is_integer(I3), is_integer(I4) -> + user_trace_int(I1, I2, I3, I4, S1, S2, S3, S4). + +-spec user_trace_int(int_p_arg(), int_p_arg(), int_p_arg(), int_p_arg(), + int_p_arg(), int_p_arg(), int_p_arg(), int_p_arg()) -> + true | false | error | badarg. + +user_trace_int(I1, I2, I3, I4, S1, S2, S3, S4) -> + UTag = get_utag(), + try + user_trace_i4s4(UTag, I1, I2, I3, I4, S1, S2, S3, S4) + catch + error:nif_not_loaded -> + false + end. + +-spec put_utag(undefined | iodata()) -> binary() | undefined. +put_utag(Data) -> + erlang:put_utag(unicode:characters_to_binary(Data)). + +-spec get_utag() -> binary() | undefined. +get_utag() -> + erlang:get_utag(). + +-spec get_utag_data() -> binary() | undefined. +%% Gets utag if set, otherwise the spread utag data from last incoming message +get_utag_data() -> + erlang:get_utag_data(). + +-spec spread_utag(boolean()) -> true | {non_neg_integer(), binary() | []}. +%% Makes the utag behave as a sequential trace token, will spread with messages to be picked up by someone using +%% get_utag_data or get_drv_utag_data. +spread_utag(B) -> + erlang:spread_utag(B). + +-spec restore_utag(true | {non_neg_integer(), binary() | []}) -> true. +restore_utag(T) -> + erlang:restore_utag(T). + + +%% Scaffolding to write tedious code: quick brute force and not 100% correct. + +scaff_int_args(N) -> + L = lists:sublist(["I1", "I2", "I3", "I4"], N), + [string:join(L, ", ")]. + +scaff_int_guards(N) -> + L = lists:sublist(["is_integer(I1)", "is_integer(I2)", "is_integer(I3)", + "is_integer(I4)"], N), + lists:flatten(string:join(L, ", ")). + +scaff_char_args(N) -> + L = lists:sublist(["S1", "S2", "S3", "S4"], N), + [string:join(L, ", ")]. + +scaff_fill(N) -> + [string:join(lists:duplicate(N, "undef"), ", ")]. + +scaff() -> + L = [begin + IntArgs = scaff_int_args(N_int), + IntGuards = scaff_int_guards(N_int), + IntFill = scaff_fill(4 - N_int), + CharArgs = scaff_char_args(N_char), + CharFill = scaff_fill(4 - N_char), + InArgs = string:join(IntArgs ++ CharArgs, ", "), + OutArgs = string:join(IntArgs ++ IntFill ++ CharArgs ++ CharFill, + ", "), + {N_int + N_char, + lists:flatten([io_lib:format("p(~s) when ~s ->\n", + [InArgs, IntGuards]), + io_lib:format(" user_trace_int(~s);\n", [OutArgs]) + ])} + end || N_int <- [0,1,2,3,4], N_char <- [0,1,2,3,4]], + [io:format("%%~p\n~s", [N, Str]) || {N, Str} <- lists:sort(L)]. -- cgit v1.2.3