Commit 1dad2ce9 authored by Lluís Vilanova's avatar Lluís Vilanova Committed by Stefan Hajnoczi
Browse files

trace: [tracetool] Minimize the amount of per-backend code 



Backends now only contain the essential backend-specific code, and most of the work is moved to frontend code.

Signed-off-by: default avatarLluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent ef0bd3bb

scripts/simpletrace.py

+1 −5
Original line number Diff line number Diff line
@@ -109,14 +109,10 @@ def process(events, log, analyzer): 
    if isinstance(log, str):

        log = open(log, 'rb')



    enabled_events = []

    dropped_event = Event.build("Dropped_Event(uint64_t num_events_dropped)")

    edict = {dropped_event_id: dropped_event}



    for e in events:

        if 'disable' not in e.properties:

            enabled_events.append(e)

    for num, event in enumerate(enabled_events):

    for num, event in enumerate(events):

        edict[num] = event



    def build_fn(analyzer, event):

scripts/tracetool/__init__.py

+2 −17
Original line number Diff line number Diff line
@@ -266,10 +266,7 @@ def generate(fevents, format, backend, 
    if not tracetool.backend.exists(backend):

        raise TracetoolError("unknown backend: %s" % backend)

    backend = backend.replace("-", "_")



    if not tracetool.backend.compatible(backend, format):

        raise TracetoolError("backend '%s' not compatible with format '%s'" %

                             (backend, format))

    backend = tracetool.backend.Wrapper(backend, format)



    import tracetool.backend.dtrace

    tracetool.backend.dtrace.BINARY = binary
@@ -277,16 +274,4 @@ def generate(fevents, format, backend, 


    events = _read_events(fevents)



    if backend == "nop":

        ( e.properies.add("disable") for e in events )



    tracetool.format.generate_begin(format, events)

    tracetool.backend.generate("nop", format,

                               [ e

                                 for e in events

                                 if "disable" in e.properties ])

    tracetool.backend.generate(backend, format,

                               [ e

                                 for e in events

                                 if "disable" not in e.properties ])

    tracetool.format.generate_end(format, events)
 
    tracetool.format.generate(events, format, backend)

scripts/tracetool/backend/__init__.py

+32 −40
Original line number Diff line number Diff line
@@ -30,17 +30,24 @@ PUBLIC If exists and is set to 'True', the backend is considered "public". 
Backend functions

-----------------



======== =======================================================================

All the following functions are optional, and no output will be generated if

they do not exist.



=============================== ==============================================

Function                        Description

======== =======================================================================

<format> Called to generate the format- and backend-specific code for each of

         the specified events. If the function does not exist, the backend is

         considered not compatible with the given format.

======== =======================================================================

=============================== ==============================================

generate_<format>_begin(events) Generate backend- and format-specific file

                                header contents.

generate_<format>_end(events)   Generate backend- and format-specific file

                                footer contents.

generate_<format>(event)        Generate backend- and format-specific contents

                                for the given event.

=============================== ==============================================



"""



__author__     = "Lluís Vilanova <vilanova@ac.upc.edu>"

__copyright__  = "Copyright 2012, Lluís Vilanova <vilanova@ac.upc.edu>"

__copyright__  = "Copyright 2012-2014, Lluís Vilanova <vilanova@ac.upc.edu>"

__license__    = "GPL version 2 or (at your option) any later version"



__maintainer__ = "Stefan Hajnoczi"
@@ -91,39 +98,24 @@ def exists(name): 
    return tracetool.try_import("tracetool.backend." + name)[1]





def compatible(backend, format):

    """Whether a backend is compatible with the given format."""

    if not exists(backend):

        raise ValueError("unknown backend: %s" % backend)



    backend = backend.replace("-", "_")

    format = format.replace("-", "_")



    if backend == "nop":

        return True

    else:

        func = tracetool.try_import("tracetool.backend." + backend,

                                    format, None)[1]

        return func is not None





def _empty(events):

    pass

class Wrapper:

    def __init__(self, backend, format):

        self._backend = backend.replace("-", "_")

        self._format = format.replace("-", "_")

        assert exists(self._backend)

        assert tracetool.format.exists(self._format)



def generate(backend, format, events):

    """Generate the per-event output for the given (backend, format) pair."""

    if not compatible(backend, format):

        raise ValueError("backend '%s' not compatible with format '%s'" %

                         (backend, format))

    def _run_function(self, name, *args, **kwargs):

        func = tracetool.try_import("tracetool.backend." + self._backend,

                                    name % self._format, None)[1]

        if func is not None:

            func(*args, **kwargs)



    backend = backend.replace("-", "_")

    format = format.replace("-", "_")

    def generate_begin(self, events):

        self._run_function("generate_%s_begin", events)



    if backend == "nop":

        func = tracetool.try_import("tracetool.format." + format,

                                    "nop", _empty)[1]

    else:

        func = tracetool.try_import("tracetool.backend." + backend,

                                    format, None)[1]

    def generate(self, event):

        self._run_function("generate_%s", event)



    func(events)
 
    def generate_end(self, events):

        self._run_function("generate_%s_end", events)

scripts/tracetool/backend/dtrace.py

+8 −71
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ PUBLIC = True 


PROBEPREFIX = None



def _probeprefix():

def probeprefix():

    if PROBEPREFIX is None:

        raise ValueError("you must set PROBEPREFIX")

    return PROBEPREFIX
@@ -29,81 +29,18 @@ def _probeprefix(): 


BINARY = None



def _binary():

def binary():

    if BINARY is None:

        raise ValueError("you must set BINARY")

    return BINARY





def c(events):

    pass





def h(events):

def generate_h_begin(events):

    out('#include "trace/generated-tracers-dtrace.h"',

        '')



    for e in events:

        out('static inline void %(api)s(%(args)s) {',

            '    QEMU_%(uppername)s(%(argnames)s);',

            '}',

            api = e.api(),

            args = e.args,

            uppername = e.name.upper(),

            argnames = ", ".join(e.args.names()),

            )





def d(events):

    out('provider qemu {')



    for e in events:

        args = str(e.args)



        # DTrace provider syntax expects foo() for empty

        # params, not foo(void)

        if args == 'void':

            args = ''



        # Define prototype for probe arguments

        out('',

            'probe %(name)s(%(args)s);',

            name = e.name,

            args = args,

            )



    out('',

        '};')





# Technically 'self' is not used by systemtap yet, but

# they recommended we keep it in the reserved list anyway

RESERVED_WORDS = (

    'break', 'catch', 'continue', 'delete', 'else', 'for',

    'foreach', 'function', 'global', 'if', 'in', 'limit',

    'long', 'next', 'probe', 'return', 'self', 'string',

    'try', 'while'

    )



def stap(events):

    for e in events:

        # Define prototype for probe arguments

        out('probe %(probeprefix)s.%(name)s = process("%(binary)s").mark("%(name)s")',

            '{',

            probeprefix = _probeprefix(),

            name = e.name,

            binary = _binary(),

            )



        i = 1

        if len(e.args) > 0:

            for name in e.args.names():

                # Append underscore to reserved keywords

                if name in RESERVED_WORDS:

                    name += '_'

                out('  %s = $arg%d;' % (name, i))

                i += 1



        out('}')



    out()
 


def generate_h(event):

    out('    QEMU_%(uppername)s(%(argnames)s);',

        uppername=event.name.upper(),

        argnames=", ".join(event.args.names()))

scripts/tracetool/backend/events.py

deleted100644 → 0
+0 −23
Original line number Diff line number Diff line 
#!/usr/bin/env python

# -*- coding: utf-8 -*-



"""

Generic event description.



This is a dummy backend to establish appropriate frontend/backend compatibility

checks.

"""



__author__     = "Lluís Vilanova <vilanova@ac.upc.edu>"

__copyright__  = "Copyright 2012, Lluís Vilanova <vilanova@ac.upc.edu>"

__license__    = "GPL version 2 or (at your option) any later version"



__maintainer__ = "Stefan Hajnoczi"

__email__      = "stefanha@linux.vnet.ibm.com"





def events_h(events):

    pass



def events_c(events):

    pass