1. 04 12月, 2009 1 次提交
  2. 02 12月, 2009 15 次提交
  3. 01 12月, 2009 12 次提交
    • X
      perf_event: Initialize data.period in perf_swevent_hrtimer() · 59d069eb
      Xiao Guangrong 提交于
      In current code in perf_swevent_hrtimer(), data.period is not
      initialized, The result is obvious wrong:
      
       # ./perf record -f -e cpu-clock make
       # ./perf report
       # Samples: 1740
       #
       # Overhead   Command                                   ......
       # ........  ........  ..........................................
       #
         1025422183050275328.00%        sh  libc-2.9.90.so ...
         1025422183050275328.00%      perl  libperl.so     ...
         1025422168240043264.00%      perl  [kernel]       ...
         1025422030011210752.00%      perl  [kernel]       ...
      Signed-off-by: NXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: <stable@kernel.org>
      LKML-Reference: <4B14E220.2050107@cn.fujitsu.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      59d069eb
    • M
      perf probe: Simplify event naming · b498ce1f
      Masami Hiramatsu 提交于
      Simplify event naming as <symbol>_<seqnum>. Each event name is
      globally unique (group name is not checked). So, if there is
      schedule_0, next probe event on schedule() will be schedule_1.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201002024.10235.2353.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      b498ce1f
    • M
      perf probe: Add --list option for listing current probe events · 4de189fe
      Masami Hiramatsu 提交于
      Add --list option for listing currently defined probe events
      in the kernel. This shows events in below format;
      
       [group:event]	<perf-probe probe-definition>
      
      for example:
      
       [probe:schedule_0]	schedule+30 cpu
      
      Note that source file/line information is not supported yet.
      So even if you added a probe by line, it will be shown in
      <symbol+offset>.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201002017.10235.76575.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      4de189fe
    • M
      perf probe: Add argv_split() from lib/argv_split.c · e1c01d61
      Masami Hiramatsu 提交于
      Add argv_split() ported from lib/argv_split.c to string.c and
      use it in util/probe-event.c.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201002005.10235.55602.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      e1c01d61
    • M
      perf probe: Move probe event utility functions to probe-event.c · 50656eec
      Masami Hiramatsu 提交于
      Split probe event (kprobe-events and perf probe events) utility
      functions from builtin-probe.c to probe-event.c.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201001958.10235.90243.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      50656eec
    • M
      perf probe: Fix probe array index for multiple probe points · 934b1f5f
      Masami Hiramatsu 提交于
      Fix the index of formatted probe array for multiple probe
      points, which should be probes[i] instead of probes[0].
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201001950.10235.54781.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      934b1f5f
    • M
      perf probe: Fix argv array size in probe parser · 74ca4c0e
      Masami Hiramatsu 提交于
      Since the syntax has been changed, probe definition needs
      parameters less than MAX_PROBE_ARGS + 1 (probe-point +
      arguments).
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201001943.10235.80367.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      74ca4c0e
    • M
      perf probe: Add probe-finder.h without libdwarf · 57d250df
      Masami Hiramatsu 提交于
      Add probe-finder.h as LIB_H without libdwarf, because that
      header is included even if no libdwarf.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201001934.10235.44656.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      57d250df
    • M
      perf probe: Change a debugging message from pr_info to pr_debug · f41b1e43
      Masami Hiramatsu 提交于
      Change annoying debug-info using notice from pr_info() to
      pr_debug(), since the message always printed when user adds a
      probe point which requires debug-info.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201001927.10235.63645.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f41b1e43
    • M
      trace_kprobes: Fix a memory leak bug and check kstrdup() return value · ba8665d7
      Masami Hiramatsu 提交于
      Fix a memory leak case in create_trace_probe(). When an argument
      is too long (> MAX_ARGSTR_LEN), it just jumps to error path. In
      that case tp->args[i].name is not released.
      This also fixes a bug to check kstrdup()'s return value.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091201001919.10235.56455.stgit@harusame>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      ba8665d7
    • L
      perf timechart: Remove open-coded event parsing code · 5cbd0805
      Li Zefan 提交于
      Convert builtin-timechart.c to mmap_dispatch_perf_file() +
      perf_file_handler.
      Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
      Acked-by: NArjan van de Ven <arjan@infradead.org>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      LKML-Reference: <4B14B21C.2040406@cn.fujitsu.com>
      [ v2: cleaned up the printout, fixed a whitespace detail ]
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      5cbd0805
    • L
      perf annotate: Fix perf data parsing · bab81b62
      Li Zefan 提交于
      perf-annotate doesn't parse perf.data correctly in that it
      doesn't read perf header. Fix this by using
      mmap_dispatch_perf_file().
      
      Before:
      
      TOTAL events:      17565
            MMAP events:       3221
            LOST events:         10
            COMM events:        235
            EXIT events:          2
        THROTTLE events:          1
      UNTHROTTLE events:          2
            FORK events:         10
            READ events:          1
          SAMPLE events:      14083
      
      After:
      
      TOTAL events:      17290
            MMAP events:       3203
            LOST events:          0
            COMM events:        234
            EXIT events:          1
        THROTTLE events:          0
      UNTHROTTLE events:          0
            FORK events:          0
            READ events:          0
          SAMPLE events:      13852
      Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Arjan van de Ven <arjan@infradead.org>
      LKML-Reference: <4B14B201.9030708@cn.fujitsu.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      bab81b62
  4. 30 11月, 2009 4 次提交
  5. 28 11月, 2009 8 次提交
    • I
      perf scripting: Fix build · cf72344d
      Ingo Molnar 提交于
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      cf72344d
    • T
      perf trace: Add a scripts/perl/bin for perf trace shell scripts · 1ae4a971
      Tom Zanussi 提交于
      To capture the relevant events for a given Perl script and to
      avoid having to continually remember and type in long
      command-lines, add a scripts/perl/bin directory containing two
      simple shell scripts for each Perl script, one for recording and
      one for processing/display. For example, to record perf data for
      the rw-by-pid.pl script, run scripts/perl/bin/rw-by-pid-record
      and to actually run the script and display the output run
      scripts/perl/bin/rw-by-pid-report.
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-8-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      1ae4a971
    • T
      perf trace: Add Documentation for perf trace Perl support · 89fbf0b8
      Tom Zanussi 提交于
      Adds perf-trace-perl Documentation and a link to it from the
      perf-trace page.
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-7-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      89fbf0b8
    • T
      perf trace: Add interface to access perf data from Perl handlers · d1b93772
      Tom Zanussi 提交于
      The Perl scripting support for perf trace allows most of a trace
      event's data to be accessed directly as handler arguments, but
      not all of it e.g. the less common fields aren't passed in.  To
      give scripts access to the other fields and/or any other data or
      metadata in the main perf executable that might be useful, a way
      to access the C data in perf from Perl is needed; this patch
      uses the Perl XS facility to do it for the common_xxx event
      fields not passed to handler functions.
      
      Context.pm exports three functions to Perl scripts that access
      fields for the current event by calling back into perf:
      common_pc(), common_flags() and common_lock_depth().  Support
      for common_flags() field values was added to Core.pm and a
      script used to sanity check these and other basic scripting
      features, check-perf-trace.pl, was also added.
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-6-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d1b93772
    • T
      perf trace: Add perf trace scripting support modules for Perl · bcefe12e
      Tom Zanussi 提交于
      Add Perf-Trace-Util Perl module and some scripts that use it.
      Core.pm contains Perl code to define and access flag and
      symbolic fields. Util.pm contains general-purpose utility
      functions.
      
      Also adds some makefile bits to install them in
      libexec/perf-core/scripts/perl (or wherever perfexec_instdir
      points).
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-5-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      bcefe12e
    • T
      perf trace: Add Perl scripting support · 16c632de
      Tom Zanussi 提交于
      Implement trace_scripting_ops to make Perl a supported perf
      trace scripting language.
      
      Additionally adds code that allows Perl trace scripts to access
      the 'flag' and 'symbolic' (__print_flags(), __print_symbolic())
      field information parsed from the trace format files.
      
      Also adds the Perl implementation of the generate_script()
      trace_scripting_op, which creates a ready-to-run perf trace Perl
      script based on existing trace data.  Scripts generated by this
      implementation print out all the fields for each event mentioned
      in perf.data (and will detect and generate the proper scripting
      code for 'flag' and 'symbolic' fields), and will additionally
      generate handlers for the special 'trace_unhandled',
      'trace_begin' and 'trace_end' handlers.  Script authors can
      simply remove the printing code to implement their own custom
      event handling.
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-4-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      16c632de
    • T
      perf trace: Add flag/symbolic format_flags · eb9a42ca
      Tom Zanussi 提交于
      It's useful to know whether a field is a flag or symbolic field
      for e.g. when generating scripts - it allows us to translate
      those fields specially rather than literally as plain numeric
      values.
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-3-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      eb9a42ca
    • T
      perf trace: Add scripting ops · 956ffd02
      Tom Zanussi 提交于
      Adds an interface, scripting_ops, that when implemented for a
      particular scripting language enables built-in support for trace
      stream processing using that language.
      
      The interface is designed to enable full-fledged language
      interpreters to be embedded inside the perf executable and
      thereby make the full capabilities of the supported languages
      available for trace processing.
      
      See below for details on the interface.
      
      This patch also adds a couple command-line options to 'perf
      trace':
      
      The -s option option is used to specify the script to be run.
      Script names that can be used with -s take the form:
      
      [language spec:]scriptname[.ext]
      
      Scripting languages register a set of 'language specs' that can
      be used to specify scripts for the registered languages.  The
      specs can be used either as prefixes or extensions.
      
      If [language spec:] is used, the script is taken as a script of
      the matching language regardless of any extension it might have.
       If [language spec:] is not used, [.ext] is used to look up the
      language it corresponds to.  Language specs are case
      insensitive.
      
      e.g. Perl scripts can be specified in the following ways:
      
      Perl:scriptname
      pl:scriptname.py # extension ignored
      PL:scriptname
      scriptname.pl
      scriptname.perl
      
      The -g [language spec] option gives users an easy starting point
      for writing scripts in the specified language.  Scripting
      support for a particular language can implement a
      generate_script() scripting op that outputs an empty (or
      near-empty) set of handlers for all the events contained in a
      given perf.data trace file - this option gives users a direct
      way to access that.
      
      Adding support for a scripting language
      ---------------------------------------
      
      The main thing that needs to be done do add support for a new
      language is to implement the scripting_ops interface:
      
      It consists of the following four functions:
      
          start_script()
          stop_script()
          process_event()
          generate_script()
      
      start_script() is called before any events are processed, and is
      meant to give the scripting language support an opportunity to
      set things up to receive events e.g. create and initialize an
      instance of a language interpreter.
      
      stop_script() is called after all events are processed, and is
      meant to give the scripting language support an opportunity to
      clean up e.g. destroy the interpreter instance, etc.
      
      process_event() is called once for each event and takes as its
      main parameter a pointer to the binary trace event record to be
      processed. The implementation is responsible for picking out the
      binary fields from the event record and sending them to the
      script handler function associated with that event e.g. a
      function derived from the event name it's meant to handle e.g.
      'sched::sched_switch()'.  The 'format' information for trace
      events can be used to parse the binary data and map it into a
      form usable by a given scripting language; see the Perl
      implemention in subsequent patches for one possible way to
      leverage the existing trace format parsing code in perf and map
      that info into specific scripting language types.
      
      generate_script() should generate a ready-to-run script for the
      current set of events in the trace, preferably with bodies that
      print out every field for each event.  Again, look at the Perl
      implementation for clues as to how that can be done.  This is an
      optional, but very useful op.
      
      Support for a given language should also add a language-specific
      setup function and call it from setup_scripting().  The
      language-specific setup function associates the the scripting
      ops for that language with one or more 'language specifiers'
      (see below) using script_spec_register().  When a script name is
      specified on the command line, the scripting ops associated with
      the specified language are used to instantiate and use the
      appropriate interpreter to process the trace stream.
      
      In general, it should be relatively easy to add support for a
      new language, especially if the language implementation supports
      an interface allowing an interpreter to be 'embedded' inside
      another program (in this case the containing program will be
      'perf trace'). If so, it should be relatively straightforward to
      translate trace events into invocations of user-defined script
      functions where e.g. the function name corresponds to the event
      type and the function parameters correspond to the event fields.
       The event and field type information exported by the event
      tracing infrastructure (via the event 'format' files) should be
      enough to parse and send any piece of trace data to the user
      script.  The easiest way to see how this can be done would be to
      look at the Perl implementation contained in
      perf/util/trace-event-perl.c/.h.
      
      There are a couple of other things that aren't covered by the
      scripting_ops or setup interface and are technically optional,
      but should be implemented if possible.  One of these is support
      for 'flag' and 'symbolic' fields e.g. being able to use more
      human-readable values such as 'GFP_KERNEL' or
      HI/BLOCK_IOPOLL/TASKLET in place of raw flag values.  See the
      Perl implementation to see how this can be done. The other thing
      is support for 'calling back' into the perf executable to access
      e.g. uncommon fields not passed by default into handler
      functions, or any metadata the implementation might want to make
      available to users via the language interface.  Again, see the
      Perl implementation for examples.
      Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
      Cc: fweisbec@gmail.com
      Cc: rostedt@goodmis.org
      Cc: anton@samba.org
      Cc: hch@infradead.org
      LKML-Reference: <1259133352-23685-2-git-send-email-tzanussi@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      956ffd02