From 864a2178d4c014a217cacf76e42b818fe9feb1d4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Llu=C3=ADs=20Vilanova?= Date: Tue, 4 Jul 2017 10:46:39 +0200 Subject: trace: [tcg] Do not generate TCG code to trace dynamically-disabled events MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If an event is dynamically disabled, the TCG code that calls the execution-time tracer is not generated. Removes the overheads of execution-time tracers for dynamically disabled events. As a bonus, also avoids checking the event state when the execution-time tracer is called from TCG-generated code (since otherwise TCG would simply not call it). Signed-off-by: Lluís Vilanova Signed-off-by: Emilio G. Cota Message-id: 149915799921.6295.13067154430923434035.stgit@frigg.lan Signed-off-by: Stefan Hajnoczi --- scripts/tracetool/__init__.py | 3 ++- scripts/tracetool/format/h.py | 26 +++++++++++++++++++------- scripts/tracetool/format/tcg_h.py | 21 +++++++++++++++++---- scripts/tracetool/format/tcg_helper_c.py | 5 +++-- 4 files changed, 41 insertions(+), 14 deletions(-) (limited to 'scripts') diff --git a/scripts/tracetool/__init__.py b/scripts/tracetool/__init__.py index 1ffbc1d..d4c204a 100644 --- a/scripts/tracetool/__init__.py +++ b/scripts/tracetool/__init__.py @@ -6,7 +6,7 @@ Machinery for generating tracing-related intermediate files. """ __author__ = "Lluís Vilanova " -__copyright__ = "Copyright 2012-2016, Lluís Vilanova " +__copyright__ = "Copyright 2012-2017, Lluís Vilanova " __license__ = "GPL version 2 or (at your option) any later version" __maintainer__ = "Stefan Hajnoczi" @@ -268,6 +268,7 @@ class Event(object): return self._FMT.findall(self.fmt) QEMU_TRACE = "trace_%(name)s" + QEMU_TRACE_NOCHECK = "_nocheck__" + QEMU_TRACE QEMU_TRACE_TCG = QEMU_TRACE + "_tcg" QEMU_DSTATE = "_TRACE_%(NAME)s_DSTATE" QEMU_EVENT = "_TRACE_%(NAME)s_EVENT" diff --git a/scripts/tracetool/format/h.py b/scripts/tracetool/format/h.py index 3682f4e..aecf249 100644 --- a/scripts/tracetool/format/h.py +++ b/scripts/tracetool/format/h.py @@ -6,7 +6,7 @@ trace/generated-tracers.h """ __author__ = "Lluís Vilanova " -__copyright__ = "Copyright 2012-2016, Lluís Vilanova " +__copyright__ = "Copyright 2012-2017, Lluís Vilanova " __license__ = "GPL version 2 or (at your option) any later version" __maintainer__ = "Stefan Hajnoczi" @@ -49,6 +49,19 @@ def generate(events, backend, group): backend.generate_begin(events, group) for e in events: + # tracer without checks + out('', + 'static inline void %(api)s(%(args)s)', + '{', + api=e.api(e.QEMU_TRACE_NOCHECK), + args=e.args) + + if "disable" not in e.properties: + backend.generate(e, group) + + out('}') + + # tracer wrapper with checks (per-vCPU tracing) if "vcpu" in e.properties: trace_cpu = next(iter(e.args))[1] cond = "trace_event_get_vcpu_state(%(cpu)s,"\ @@ -63,16 +76,15 @@ def generate(events, backend, group): 'static inline void %(api)s(%(args)s)', '{', ' if (%(cond)s) {', + ' %(api_nocheck)s(%(names)s);', + ' }', + '}', api=e.api(), + api_nocheck=e.api(e.QEMU_TRACE_NOCHECK), args=e.args, + names=", ".join(e.args.names()), cond=cond) - if "disable" not in e.properties: - backend.generate(e, group) - - out(' }', - '}') - backend.generate_end(events, group) out('#endif /* TRACE_%s_GENERATED_TRACERS_H */' % group.upper()) diff --git a/scripts/tracetool/format/tcg_h.py b/scripts/tracetool/format/tcg_h.py index db55f52..1651cc3 100644 --- a/scripts/tracetool/format/tcg_h.py +++ b/scripts/tracetool/format/tcg_h.py @@ -6,7 +6,7 @@ Generate .h file for TCG code generation. """ __author__ = "Lluís Vilanova " -__copyright__ = "Copyright 2012-2016, Lluís Vilanova " +__copyright__ = "Copyright 2012-2017, Lluís Vilanova " __license__ = "GPL version 2 or (at your option) any later version" __maintainer__ = "Stefan Hajnoczi" @@ -46,7 +46,7 @@ def generate(events, backend, group): for e in events: # just keep one of them - if "tcg-trans" not in e.properties: + if "tcg-exec" not in e.properties: continue out('static inline void %(name_tcg)s(%(args)s)', @@ -58,12 +58,25 @@ def generate(events, backend, group): args_trans = e.original.event_trans.args args_exec = tracetool.vcpu.transform_args( "tcg_helper_c", e.original.event_exec, "wrapper") + if "vcpu" in e.properties: + trace_cpu = e.args.names()[0] + cond = "trace_event_get_vcpu_state(%(cpu)s,"\ + " TRACE_%(id)s)"\ + % dict( + cpu=trace_cpu, + id=e.original.event_exec.name.upper()) + else: + cond = "true" + out(' %(name_trans)s(%(argnames_trans)s);', - ' gen_helper_%(name_exec)s(%(argnames_exec)s);', + ' if (%(cond)s) {', + ' gen_helper_%(name_exec)s(%(argnames_exec)s);', + ' }', name_trans=e.original.event_trans.api(e.QEMU_TRACE), name_exec=e.original.event_exec.api(e.QEMU_TRACE), argnames_trans=", ".join(args_trans.names()), - argnames_exec=", ".join(args_exec.names())) + argnames_exec=", ".join(args_exec.names()), + cond=cond) out('}') diff --git a/scripts/tracetool/format/tcg_helper_c.py b/scripts/tracetool/format/tcg_helper_c.py index ec7acbe..bbbd6ad 100644 --- a/scripts/tracetool/format/tcg_helper_c.py +++ b/scripts/tracetool/format/tcg_helper_c.py @@ -6,7 +6,7 @@ Generate trace/generated-helpers.c. """ __author__ = "Lluís Vilanova " -__copyright__ = "Copyright 2012-2016, Lluís Vilanova " +__copyright__ = "Copyright 2012-2017, Lluís Vilanova " __license__ = "GPL version 2 or (at your option) any later version" __maintainer__ = "Stefan Hajnoczi" @@ -71,10 +71,11 @@ def generate(events, backend, group): out('void %(name_tcg)s(%(args_api)s)', '{', + # NOTE: the check was already performed at TCG-generation time ' %(name)s(%(args_call)s);', '}', name_tcg="helper_%s_proxy" % e.api(), - name=e.api(), + name=e.api(e.QEMU_TRACE_NOCHECK), args_api=e_args_api, args_call=", ".join(e_args_call.casted()), ) -- cgit v1.1