diff options
Diffstat (limited to 'erts/doc/src')
| -rw-r--r-- | erts/doc/src/erl_tracer.xml | 62 | ||||
| -rw-r--r-- | erts/doc/src/erts_alloc.xml | 2 | ||||
| -rw-r--r-- | erts/doc/src/match_spec.xml | 149 |
3 files changed, 115 insertions, 98 deletions
diff --git a/erts/doc/src/erl_tracer.xml b/erts/doc/src/erl_tracer.xml index 7fd5512b33..d4c8bbad31 100644 --- a/erts/doc/src/erl_tracer.xml +++ b/erts/doc/src/erl_tracer.xml @@ -67,7 +67,7 @@ <desc> <p>The different trace tags that the tracer will be called with. Each trace tag is described in greater detail in - <seealso marker="#trace">Module:trace/6</seealso> + <seealso marker="#Module:trace/6">Module:trace/6</seealso> </p> </desc> </datatype> @@ -81,7 +81,7 @@ <datatype> <name name="trace_opts" /> <desc> - <p>The options for the tracee. + <p>The options for the tracee.</p> <taglist> <tag><c>timestamp</c></tag> <item>If not set to <c>undefined</c>, the tracer has been requested to @@ -93,7 +93,6 @@ <item>Set to a number if the scheduler id is to be included by the tracer. Otherwise it is set to <c>undefined</c>.</item> </taglist> - </p> </desc> </datatype> <datatype> @@ -114,30 +113,30 @@ <p>The following functions should be exported from a <c>erl_tracer</c> callback module.</p> <taglist> - <tag><seealso marker="#enabled"><c>Module:enabled/3</c></seealso></tag> + <tag><seealso marker="#Module:enabled/3"><c>Module:enabled/3</c></seealso></tag> <item>Mandatory</item> - <tag><seealso marker="#trace"><c>Module:trace/6</c></seealso></tag> + <tag><seealso marker="#Module:trace/6"><c>Module:trace/6</c></seealso></tag> <item>Mandatory</item> - <tag><seealso marker="#enabled_procs"><c>Module:enabled_procs/3</c></seealso></tag> + <tag><seealso marker="#Module:enabled_procs/3"><c>Module:enabled_procs/3</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#trace_procs"><c>Module:trace_procs/6</c></seealso></tag> + <tag><seealso marker="#Module:trace_procs/6"><c>Module:trace_procs/6</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#enabled_ports"><c>Module:enabled_ports/3</c></seealso></tag> + <tag><seealso marker="#Module:enabled_ports/3"><c>Module:enabled_ports/3</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#trace_ports"><c>Module:trace_ports/6</c></seealso></tag> + <tag><seealso marker="#Module:trace_ports/6"><c>Module:trace_ports/6</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#enabled_running_ports"><c>Module:enabled_running_ports/3</c></seealso></tag> + <tag><seealso marker="#Module:enabled_running_ports/3"><c>Module:enabled_running_ports/3</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#trace_running_ports"><c>Module:trace_running_ports/6</c></seealso></tag> + <tag><seealso marker="#Module:trace_running_ports/6"><c>Module:trace_running_ports/6</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#enabled_running_procs"><c>Module:enabled_running_procs/3</c></seealso></tag> + <tag><seealso marker="#Module:enabled_running_procs/3"><c>Module:enabled_running_procs/3</c></seealso></tag> <item>Optional</item> - <tag><seealso marker="#trace_running_procs"><c>Module:trace_running_procs/6</c></seealso></tag> + <tag><seealso marker="#Module:trace_running_procs/6"><c>Module:trace_running_procs/6</c></seealso></tag> <item>Optional</item> </taglist> </section> - <marker id="enabled"></marker> + <funcs> <func> <name>Module:enabled(TraceTag, TracerState, Tracee) -> Result</name> @@ -166,7 +165,6 @@ is important that it is both fast and side effect free.</p> </desc> </func> - <marker id="trace"></marker> <func> <name>Module:trace(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -181,7 +179,7 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled">Module:enabled/3</seealso> + the <seealso marker="#Module:enabled/3">Module:enabled/3</seealso> callback returned <c>trace</c>. In it any side effects needed by the tracer should be done. The tracepoint payload is located in the <c>FirstTraceTerm</c> and <c>SecondTraceTerm</c>. The content @@ -212,7 +210,6 @@ </desc> </func> - <marker id="enabled_procs"></marker> <func> <name>Module:enabled_procs(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -230,7 +227,6 @@ </desc> </func> - <marker id="trace_procs"></marker> <func> <name>Module:trace_procs(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -245,13 +241,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_procs">Module:enabled_procs/3</seealso> + the <seealso marker="#Module:enabled_procs/3">Module:enabled_procs/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_procs/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_ports"></marker> <func> <name>Module:enabled_ports(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -269,7 +264,6 @@ </desc> </func> - <marker id="trace_ports"></marker> <func> <name>Module:trace_ports(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -284,13 +278,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_ports">Module:enabled_ports/3</seealso> + the <seealso marker="#Module:enabled_ports/3">Module:enabled_ports/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_ports/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_running_procs"></marker> <func> <name>Module:enabled_running_procs(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -308,7 +301,6 @@ </desc> </func> - <marker id="trace_running_procs"></marker> <func> <name>Module:trace_running_procs(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -323,13 +315,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_running_procs">Module:enabled_running_procs/3</seealso> + the <seealso marker="#Module:enabled_running_procs/3">Module:enabled_running_procs/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_running_procs/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_running_ports"></marker> <func> <name>Module:enabled_running_ports(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -347,7 +338,6 @@ </desc> </func> - <marker id="trace_running_ports"></marker> <func> <name>Module:trace_running_ports(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -362,13 +352,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_running_ports">Module:enabled_running_ports/3</seealso> + the <seealso marker="#Module:enabled_running_ports/3">Module:enabled_running_ports/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_running_ports/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_call"></marker> <func> <name>Module:enabled_call(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -386,7 +375,6 @@ </desc> </func> - <marker id="trace_call"></marker> <func> <name>Module:trace_call(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -401,13 +389,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_call">Module:enabled_call/3</seealso> + the <seealso marker="#Module:enabled_call/3">Module:enabled_call/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_call/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_send"></marker> <func> <name>Module:enabled_send(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -425,7 +412,6 @@ </desc> </func> - <marker id="trace_send"></marker> <func> <name>Module:trace_send(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -440,13 +426,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_send">Module:enabled_send/3</seealso> + the <seealso marker="#Module:enabled_send/3">Module:enabled_send/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_send/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_receive"></marker> <func> <name>Module:enabled_receive(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -464,7 +449,6 @@ </desc> </func> - <marker id="trace_receive"></marker> <func> <name>Module:trace_receive(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -479,13 +463,12 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_receive">Module:enabled_receive/3</seealso> + the <seealso marker="#Module:enabled_receive/3">Module:enabled_receive/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_receive/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> </func> - <marker id="enabled_garbage_collection"></marker> <func> <name>Module:enabled_garbage_collection(TraceTag, TracerState, Tracee) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -503,7 +486,6 @@ </desc> </func> - <marker id="trace_garbage_collection"></marker> <func> <name>Module:trace_garbage_collection(TraceTag, TracerState, Tracee, FirstTraceTerm, SecondTraceTerm, Opts) -> Result</name> <fsummary>Check if a trace event should be generated.</fsummary> @@ -518,7 +500,7 @@ </type> <desc> <p>This callback will be called when a tracepoint is triggered and - the <seealso marker="#enabled_garbage_collection">Module:enabled_garbage_collection/3</seealso> + the <seealso marker="#Module:enabled_garbage_collection/3">Module:enabled_garbage_collection/3</seealso> callback returned <c>trace</c>.</p> <p>If <c>trace_garbage_collection/6</c> is not defined <c>trace/6</c> will be called instead.</p> </desc> diff --git a/erts/doc/src/erts_alloc.xml b/erts/doc/src/erts_alloc.xml index 70775b9f0f..9aef1c0b1f 100644 --- a/erts/doc/src/erts_alloc.xml +++ b/erts/doc/src/erts_alloc.xml @@ -583,7 +583,7 @@ </taglist> <p>The following flag is special for <c>exec_alloc</c>:</p> <taglist> - <tag><marker id="MIscs"/><c><![CDATA[+MXscs <size in MB>]]></c></tag> + <tag><marker id="MXscs"/><c><![CDATA[+MXscs <size in MB>]]></c></tag> <item> <c>exec_alloc</c> super carrier size (in MB). The amount of <em>virtual</em> address space reserved for native executable code diff --git a/erts/doc/src/match_spec.xml b/erts/doc/src/match_spec.xml index 3944f24f84..7be3d15de6 100644 --- a/erts/doc/src/match_spec.xml +++ b/erts/doc/src/match_spec.xml @@ -33,21 +33,15 @@ <file>match_spec.xml</file> </header> <p>A "match specification" (match_spec) is an Erlang term describing a - small "program" that will try to match something (either the - parameters to a function as used in the <c><![CDATA[erlang:trace_pattern/2]]></c> - BIF, or the objects in an ETS table.). + small "program" that will try to match something. It can be used + to either control tracing with + <seealso marker="erlang#trace_pattern/3">erlang:trace_pattern/3</seealso> + or to search for objects in an ETS table with for example + <seealso marker="stdlib:ets#select/2">ets:select/2</seealso>. The match_spec in many ways works like a small function in Erlang, but is interpreted/compiled by the Erlang runtime system to something much more efficient than calling an Erlang function. The match_spec is also very limited compared to the expressiveness of real Erlang functions.</p> - <p>Match specifications are given to the BIF <c><![CDATA[erlang:trace_pattern/2]]></c> to - execute matching of function arguments as well as to define some actions - to be taken when the match succeeds (the <c><![CDATA[MatchBody]]></c> part). Match - specifications can also be used in ETS, to specify objects to be - returned from an <c><![CDATA[ets:select/2]]></c> call (or other select - calls). The semantics and restrictions differ slightly when using - match specifications for tracing and in ETS, the differences are - defined in a separate paragraph below.</p> <p>The most notable difference between a match_spec and an Erlang fun is of course the syntax. Match specifications are Erlang terms, not Erlang code. A match_spec also has a somewhat strange concept of @@ -382,6 +376,51 @@ the pid() of the current process.</p> </section> + <marker id="match_target"></marker> + <section> + <title>Match target</title> + <p>Each execution of a match specification is done against + a match target term. The format and content of the target term + depends on the context in which the match is done. The match + target for ETS is always a full table tuple. The match target + for call trace is always a list of all function arguments. The + match target for event trace depends on the event type, see + table below.</p> + <table> + <row> + <cell align="left" valign="middle">Context</cell> + <cell align="left" valign="middle">Type</cell> + <cell align="left" valign="middle">Match target</cell> + <cell align="left" valign="middle">Description</cell> + </row> + <row> + <cell align="left" valign="middle">ETS</cell> + <cell align="left" valign="middle"></cell> + <cell align="left" valign="middle">{Key, Value1, Value2, ...}</cell> + <cell align="left" valign="middle">A table object</cell> + </row> + <row> + <cell align="left" valign="middle">Trace</cell> + <cell align="left" valign="middle">call</cell> + <cell align="left" valign="middle">[Arg1, Arg2, ...]</cell> + <cell align="left" valign="middle">Function arguments</cell> + </row> + <row> + <cell align="left" valign="middle">Trace</cell> + <cell align="left" valign="middle">send</cell> + <cell align="left" valign="middle">[Receiver, Message]</cell> + <cell align="left" valign="middle">Receiving process/port and message term</cell> + </row> + <row> + <cell align="left" valign="middle">Trace</cell> + <cell align="left" valign="middle">'receive'</cell> + <cell align="left" valign="middle">[Node, Sender, Message]</cell> + <cell align="left" valign="middle">Sending node, process/port and message term</cell> + </row> + <tcaption>Match target depending on context</tcaption> + </table> + </section> + <section> <title>Variables and literals</title> <p>Variables take the form <c><![CDATA['$<number>']]></c> where @@ -396,10 +435,8 @@ <c><![CDATA[MatchCondition]]></c> parts, only variables bound previously may be used. As a special case, in the <c><![CDATA[MatchCondition/MatchBody]]></c> parts, the variable <c><![CDATA['$_']]></c> - expands to the whole expression which matched the - <c><![CDATA[MatchHead]]></c> (i.e., the whole parameter list to the possibly - traced function or the whole matching object in the ets table) - and the variable <c><![CDATA['$$']]></c> expands to a list + expands to the whole <seealso marker="#match_target">match target</seealso> + term and the variable <c><![CDATA['$$']]></c> expands to a list of the values of all bound variables in order (i.e. <c><![CDATA[['$1','$2', ...]]]></c>). </p> @@ -480,8 +517,8 @@ <p>For each tuple in the <c><![CDATA[MatchExpression]]></c> list and while no match has succeeded:</p> <list type="bulleted"> - <item>Match the <c><![CDATA[MatchHead]]></c> part against the arguments to the - function, + <item>Match the <c><![CDATA[MatchHead]]></c> part against the + match target term, binding the <c><![CDATA['$<number>']]></c> variables (much like in <c><![CDATA[ets:match/2]]></c>). If the <c><![CDATA[MatchHead]]></c> cannot match the arguments, the match fails. @@ -522,13 +559,10 @@ term. The <c><![CDATA[ActionTerm]]></c>'s are executed as in an imperative language, i.e. for their side effects. Functions with side effects are also allowed when tracing.</p> - <p>In ETS the match head is a <c><![CDATA[tuple()]]></c> (or a single match - variable) while it is a list (or a single match variable) when - tracing.</p> </section> <section> - <title>ETS Examples</title> + <title>Tracing Examples</title> <p>Match an argument list of three where the first and third arguments are equal:</p> <code type="none"><![CDATA[ @@ -585,42 +619,6 @@ parameter list with a single variable is a special case. In all other cases the <c><![CDATA[MatchHead]]></c> has to be a <em>proper</em> list. </p> - <p>Match all objects in an ets table where the first element is - the atom 'strider' and the tuple arity is 3 and return the whole - object.</p> - <code type="none"><![CDATA[ -[{{strider,'_','_'}, - [], - ['$_']}] - ]]></code> - <p>Match all objects in an ets table with arity > 1 and the first - element is 'gandalf', return element 2.</p> - <code type="none"><![CDATA[ -[{'$1', - [{'==', gandalf, {element, 1, '$1'}},{'>=',{size, '$1'},2}], - [{element,2,'$1'}]}] - ]]></code> - <p>In the above example, if the first element had been the key, - it's much more efficient to match that key in the <c><![CDATA[MatchHead]]></c> - part than in the <c><![CDATA[MatchConditions]]></c> part. The search space of - the tables is restricted with regards to the <c><![CDATA[MatchHead]]></c> so - that only objects with the matching key are searched. - </p> - <p>Match tuples of 3 elements where the second element is either - 'merry' or 'pippin', return the whole objects.</p> - <code type="none"><![CDATA[ -[{{'_',merry,'_'}, - [], - ['$_']}, - {{'_',pippin,'_'}, - [], - ['$_']}] - ]]></code> - <p>The function <c><![CDATA[ets:test_ms/2]]></c> can be useful for testing - complicated ets matches.</p> - </section> - <section> - <title>Tracing Examples</title> <p>Only generate trace message if trace control word is set to 1:</p> <code type="none"><![CDATA[ [{'_', @@ -658,5 +656,42 @@ {'_',[],[]}] ]]></code> </section> + + <section> + <title>ETS Examples</title> + <p>Match all objects in an ets table where the first element is + the atom 'strider' and the tuple arity is 3 and return the whole + object.</p> + <code type="none"><![CDATA[ +[{{strider,'_','_'}, + [], + ['$_']}] + ]]></code> + <p>Match all objects in an ets table with arity > 1 and the first + element is 'gandalf', return element 2.</p> + <code type="none"><![CDATA[ +[{'$1', + [{'==', gandalf, {element, 1, '$1'}},{'>=',{size, '$1'},2}], + [{element,2,'$1'}]}] + ]]></code> + <p>In the above example, if the first element had been the key, + it's much more efficient to match that key in the <c><![CDATA[MatchHead]]></c> + part than in the <c><![CDATA[MatchConditions]]></c> part. The search space of + the tables is restricted with regards to the <c><![CDATA[MatchHead]]></c> so + that only objects with the matching key are searched. + </p> + <p>Match tuples of 3 elements where the second element is either + 'merry' or 'pippin', return the whole objects.</p> + <code type="none"><![CDATA[ +[{{'_',merry,'_'}, + [], + ['$_']}, + {{'_',pippin,'_'}, + [], + ['$_']}] + ]]></code> + <p>The function <c><![CDATA[ets:test_ms/2]]></c> can be useful for testing + complicated ets matches.</p> + </section> </chapter> |