Commit 40b9cd25 authored by Lluís Vilanova's avatar Lluís Vilanova Committed by Stefan Hajnoczi
Browse files

trace: Conditionally trace events based on their per-vCPU state 



Events with the 'vcpu' property are conditionally emitted according to
their per-vCPU state. Other events are emitted normally based on their
global tracing state.

Note that the per-vCPU condition check applies to all tracing backends.

Signed-off-by: default avatarLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 48151859

scripts/tracetool/backend/dtrace.py

+2 −2
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ DTrace/SystemTAP backend. 
"""



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

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

__copyright__  = "Copyright 2012-2016, Lluís Vilanova <vilanova@ac.upc.edu>"

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



__maintainer__ = "Stefan Hajnoczi"

scripts/tracetool/backend/log.py

+16 −10
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ Stderr built-in backend. 
"""



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

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

__copyright__  = "Copyright 2012-2016, Lluís Vilanova <vilanova@ac.upc.edu>"

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



__maintainer__ = "Stefan Hajnoczi"
@@ -30,7 +30,13 @@ def generate_h(event): 
    if len(event.args) > 0:

        argnames = ", " + argnames



    out('    if (trace_event_get_state(%(event_id)s)) {',

    if "vcpu" in event.properties:

        # already checked on the generic format code

        cond = "true"

    else:

        cond = "trace_event_get_state(%s)" % ("TRACE_" + event.name.upper())



    out('        if (%(cond)s) {',

        '            struct timeval _now;',

        '            gettimeofday(&_now, NULL);',

        '            qemu_log_mask(LOG_TRACE, "%%d@%%zd.%%06zd:%(name)s " %(fmt)s "\\n",',
@@ -38,7 +44,7 @@ def generate_h(event): 
        '                          (size_t)_now.tv_sec, (size_t)_now.tv_usec',

        '                          %(argnames)s);',

        '        }',

        event_id="TRACE_" + event.name.upper(),

        cond=cond,

        name=event.name,

        fmt=event.fmt.rstrip("\n"),

        argnames=argnames)

scripts/tracetool/backend/simple.py

+10 −3
Original line number Diff line number Diff line
@@ -68,16 +68,23 @@ def generate_c(event): 
    if len(event.args) == 0:

        sizestr = '0'



    event_id = 'TRACE_' + event.name.upper()

    if "vcpu" in event.properties:

        # already checked on the generic format code

        cond = "true"

    else:

        cond = "trace_event_get_state(%s)" % event_id



    out('',

        '    if (!trace_event_get_state(%(event_id)s)) {',

        '    if (!%(cond)s) {',

        '        return;',

        '    }',

        '',

        '    if (trace_record_start(&rec, %(event_id)s, %(size_str)s)) {',

        '        return; /* Trace Buffer Full, Event Dropped ! */',

        '    }',

        event_id='TRACE_' + event.name.upper(),

        cond=cond,

        event_id=event_id,

        size_str=sizestr)



    if len(event.args) > 0:

scripts/tracetool/backend/ust.py

+2 −2
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ LTTng User Space Tracing backend. 
"""



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

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

__copyright__  = "Copyright 2012-2016, Lluís Vilanova <vilanova@ac.upc.edu>"

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



__maintainer__ = "Stefan Hajnoczi"

scripts/tracetool/format/h.py

+17 −2
Original line number Diff line number Diff line
@@ -23,21 +23,36 @@ def generate(events, backend): 
        '#define TRACE__GENERATED_TRACERS_H',

        '',

        '#include "qemu-common.h"',

        '#include "trace/control.h"',

        '')



    backend.generate_begin(events)



    for e in events:

        if "vcpu" in e.properties:

            trace_cpu = next(iter(e.args))[1]

            cond = "trace_event_get_vcpu_state(%(cpu)s,"\

                   " TRACE_%(id)s,"\

                   " TRACE_VCPU_%(id)s)"\

                   % dict(

                       cpu=trace_cpu,

                       id=e.name.upper())

        else:

            cond = "true"



        out('',

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

            '{',

            '    if (%(cond)s) {',

            api=e.api(),

            args=e.args)

            args=e.args,

            cond=cond)



        if "disable" not in e.properties:

            backend.generate(e)



        out('}')

        out('    }',

            '}')



    backend.generate_end(events)

scripts/tracetool/backend/ftrace.py

+10 −10

File changed.

Contains only whitespace changes.