Re: [Qemu-devel] [PATCH v3 03/24] trace: Let the user specify her own trace-events file

[Paolo Bonzini <pbonzini@redhat.com>]

Il 21/04/2013 21:11, Lluís Vilanova ha scritto:
> With this option the user can perform multiple builds of QEMU with different
> tracing event properties.

I don't understand why this is useful?  If it is just to add/remove
"disable" here and there, surely the user should be using git and
different branches?

Paolo

> Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
> ---
>  Makefile.target     |    2 +-
>  configure           |   19 +++++++++++++++++++
>  trace/Makefile.objs |   10 +++++-----
>  3 files changed, 25 insertions(+), 6 deletions(-)
> 
> diff --git a/Makefile.target b/Makefile.target
> index 2bd6d14..f382559 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -47,7 +47,7 @@ else
>  TARGET_TYPE=system
>  endif
>  
> -$(QEMU_PROG).stp: $(SRC_PATH)/trace-events
> +$(QEMU_PROG).stp: $(TRACE_EVENTS)
>  	$(call quiet-command,$(TRACETOOL) \
>  		--format=stap \
>  		--backend=$(TRACE_BACKEND) \
> diff --git a/configure b/configure
> index 73df181..a3bd336 100755
> --- a/configure
> +++ b/configure
> @@ -221,6 +221,7 @@ blobs="yes"
>  pkgversion=""
>  pie=""
>  zero_malloc=""
> +trace_events=`dirname $0`/trace-events
>  trace_backend="nop"
>  trace_file="trace"
>  spice=""
> @@ -639,6 +640,8 @@ for opt do
>    ;;
>    --target-list=*) target_list="$optarg"
>    ;;
> +  --with-trace-events=*) trace_events="$optarg"
> +  ;;
>    --enable-trace-backend=*) trace_backend="$optarg"
>    ;;
>    --with-trace-file=*) trace_file="$optarg"
> @@ -1158,6 +1161,7 @@ echo "  --enable-docs            enable documentation build"
>  echo "  --disable-docs           disable documentation build"
>  echo "  --disable-vhost-net      disable vhost-net acceleration support"
>  echo "  --enable-vhost-net       enable vhost-net acceleration support"
> +echo "  --with-trace-events=PATH file with tracing events description (default: $trace_events)"
>  echo "  --enable-trace-backend=B Set trace backend"
>  echo "                           Available backends:" $($python "$source_path"/scripts/tracetool.py --list-backends)
>  echo "  --with-trace-file=NAME   Full PATH,NAME of file to store traces"
> @@ -3009,6 +3013,18 @@ if compile_prog "" "" ; then
>  fi
>  
>  ##########################################
> +# check if trace-events file exists
> +
> +if test ! -f "$trace_events"; then
> +    echo
> +    echo "Error: the given trace-events file does not exist"
> +    echo
> +    exit 1
> +else
> +    trace_events=`readlink -f "$trace_events"`
> +fi
> +
> +##########################################
>  # check if trace backend exists
>  
>  $python "$source_path/scripts/tracetool.py" "--backend=$trace_backend" --check-backend  > /dev/null 2> /dev/null
> @@ -3418,6 +3434,7 @@ echo "sigev_thread_id   $sigev_thread_id"
>  echo "uuid support      $uuid"
>  echo "libcap-ng support $cap_ng"
>  echo "vhost-net support $vhost_net"
> +echo "Trace events      $trace_events"
>  echo "Trace backend     $trace_backend"
>  echo "Trace output file $trace_file-<pid>"
>  echo "spice support     $spice ($spice_protocol_version/$spice_server_version)"
> @@ -3810,6 +3827,8 @@ bsd)
>  ;;
>  esac
>  
> +echo "TRACE_EVENTS=$trace_events" >> $config_host_mak
> +
>  # use default implementation for tracing backend-specific routines
>  trace_default=yes
>  echo "TRACE_BACKEND=$trace_backend" >> $config_host_mak
> diff --git a/trace/Makefile.objs b/trace/Makefile.objs
> index a043072..bf0a965 100644
> --- a/trace/Makefile.objs
> +++ b/trace/Makefile.objs
> @@ -4,7 +4,7 @@
>  # Auto-generated event descriptions
>  
>  $(obj)/generated-events.h: $(obj)/generated-events.h-timestamp
> -$(obj)/generated-events.h-timestamp: $(SRC_PATH)/trace-events
> +$(obj)/generated-events.h-timestamp: $(TRACE_EVENTS)
>  	$(call quiet-command,$(TRACETOOL) \
>  		--format=events-h \
>  		--backend=events \
> @@ -12,7 +12,7 @@ $(obj)/generated-events.h-timestamp: $(SRC_PATH)/trace-events
>  	@cmp -s $@ $(patsubst %-timestamp,%,$@) || cp $@ $(patsubst %-timestamp,%,$@)
>  
>  $(obj)/generated-events.c: $(obj)/generated-events.c-timestamp $(BUILD_DIR)/config-host.mak
> -$(obj)/generated-events.c-timestamp: $(SRC_PATH)/trace-events
> +$(obj)/generated-events.c-timestamp: $(TRACE_EVENTS)
>  	$(call quiet-command,$(TRACETOOL) \
>  		--format=events-c \
>  		--backend=events \
> @@ -27,7 +27,7 @@ util-obj-y += generated-events.o
>  
>  $(obj)/generated-tracers.h: $(obj)/generated-tracers.h-timestamp
>  	@cmp -s $< $@ || cp $< $@
> -$(obj)/generated-tracers.h-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/config-host.mak
> +$(obj)/generated-tracers.h-timestamp: $(TRACE_EVENTS) $(BUILD_DIR)/config-host.mak
>  	$(call quiet-command,$(TRACETOOL) \
>  		--format=h \
>  		--backend=$(TRACE_BACKEND) \
> @@ -39,7 +39,7 @@ $(obj)/generated-tracers.h-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/conf
>  ifneq ($(TRACE_BACKEND),dtrace)
>  $(obj)/generated-tracers.c: $(obj)/generated-tracers.c-timestamp
>  	@cmp -s $< $@ || cp $< $@
> -$(obj)/generated-tracers.c-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/config-host.mak
> +$(obj)/generated-tracers.c-timestamp: $(TRACE_EVENTS) $(BUILD_DIR)/config-host.mak
>  	$(call quiet-command,$(TRACETOOL) \
>  		--format=c \
>  		--backend=$(TRACE_BACKEND) \
> @@ -57,7 +57,7 @@ endif
>  # rule file. So we use '.dtrace' instead
>  ifeq ($(TRACE_BACKEND),dtrace)
>  $(obj)/generated-tracers.dtrace: $(obj)/generated-tracers.dtrace-timestamp
> -$(obj)/generated-tracers.dtrace-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/config-host.mak
> +$(obj)/generated-tracers.dtrace-timestamp: $(TRACE_EVENTS) $(BUILD_DIR)/config-host.mak
>  	$(call quiet-command,$(TRACETOOL) \
>  		--format=d \
>  		--backend=$(TRACE_BACKEND) \
> 
> 
>