| Message ID | 1287410646-10129-1-git-send-email-berrange@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Oct 18, 2010 at 3:04 PM, Daniel P. Berrange <berrange@redhat.com> wrote: > This introduces a new tracing backend that targets the SystemTAP > implementation of DTrace userspace tracing. The core functionality > should be applicable and standard across any DTrace implementation > on Solaris, OS-X, *BSD, but the Makefile rules will likely need > some small additional changes to cope with OS specific build > requirements. Cool, I will try this patch out shortly. Here a few comments: DTrace detection in ./configure would help users trying out --trace-backend=dtrace on systems without SystemTAP installed. Perhaps running dtrace(1) is a sufficient test? If SystemTAP is not installed then an error message from ./configure will save users time. > > This backend builds a little differently from the other tracing > backends. Specifically there is no 'trace.c' file, because the > 'dtrace' command line tool generates a '.o' file directly from > the dtrace probe definition file. The probe definition is usually > named with a '.d' extension but QEMU uses '.d' files for its > external makefile dependancy tracking, so this uses '.dtrace' as > the extension for the probe definition file. > > The 'tracetool' program gains the ability to generate a trace.h > file for DTrace, and also to generate the trace.d file containing > the dtrace probe definition, and finally a qemu.stp file which is > a wrapper around the probe definition providing more convenient > access from SystemTAP scripts. > > eg, instead of > > probe process("qemu").mark("qemu_malloc") { > printf("Malloc %d %p\n", $arg1, $arg2); > } > > The addition of qemu.stp to /usr/share/systemtap/tapset/ > lets users write > > probe qemu.qemu_malloc { > printf("Malloc %d %p\n", size, ptr); > } > > * .gitignore: Ignore trace-dtrace.* > * Makefile: Extra rules for generating DTrace files > * Makefile.obj: Don't build trace.o for DTrace, use > trace-dtrace.o generated by 'dtrace' instead > * tracetool: Support for generating DTrace/SystemTAP > data files > > Signed-off-by: Daniel P. Berrange <berrange@redhat.com> > --- > .gitignore | 3 + > Makefile | 31 ++++++++++ > Makefile.objs | 4 + > tracetool | 175 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- > 4 files changed, 211 insertions(+), 2 deletions(-) > > diff --git a/.gitignore b/.gitignore > index a43e4d1..0d27afd 100644 > --- a/.gitignore > +++ b/.gitignore > @@ -4,6 +4,9 @@ config-host.* > config-target.* > trace.h > trace.c > +trace-dtrace.h > +trace-dtrace.dtrace > +qemu.stp > *-timestamp > *-softmmu > *-darwin-user > diff --git a/Makefile b/Makefile > index 252c817..812b0d3 100644 > --- a/Makefile > +++ b/Makefile > @@ -1,6 +1,9 @@ > # Makefile for QEMU. > > GENERATED_HEADERS = config-host.h trace.h > +ifeq ($(TRACE_BACKEND),dtrace) > +GENERATED_HEADERS += trace-dtrace.h > +endif > > ifneq ($(wildcard config-host.mak),) > # Put the all: rule here so that config-host.mak can contain dependencies. > @@ -106,7 +109,11 @@ ui/vnc.o: QEMU_CFLAGS += $(VNC_TLS_CFLAGS) > > bt-host.o: QEMU_CFLAGS += $(BLUEZ_CFLAGS) > > +ifeq ($(TRACE_BACKEND),dtrace) > +trace.h: trace.h-timestamp trace-dtrace.h > +else > trace.h: trace.h-timestamp > +endif > trace.h-timestamp: $(SRC_PATH)/trace-events config-host.mak > $(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -h < $< > $@," GEN trace.h") > @cmp -s $@ trace.h || cp $@ trace.h > @@ -118,6 +125,23 @@ trace.c-timestamp: $(SRC_PATH)/trace-events config-host.mak > > trace.o: trace.c $(GENERATED_HEADERS) > > +trace-dtrace.h: trace-dtrace.dtrace > + $(call quiet-command,dtrace -o $@ -h -s $<, " GEN trace-dtrace.h") > + > +# Normal practice is to name DTrace probe file with a '.d' extension > +# but that gets picked up by QEMU's Makefile as an external dependancy > +# rule file. So we use '.dtrace' instead > +trace-dtrace.dtrace: trace-dtrace.dtrace-timestamp > +trace-dtrace.dtrace-timestamp: $(SRC_PATH)/trace-events config-host.mak > + $(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -d < $< > $@," GEN trace-dtrace.dtrace") > + @cmp -s $@ trace-dtrace.dtrace || cp $@ trace-dtrace.dtrace > +ifdef CONFIG_LINUX > + $(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -s < $< > qemu.stp," GEN qemu.stp") > +endif > + > +trace-dtrace.o: trace-dtrace.dtrace $(GENERATED_HEADERS) > + $(call quiet-command,dtrace -o $@ -G -s $<, " GEN trace-dtrace.o") > + > simpletrace.o: simpletrace.c $(GENERATED_HEADERS) > > version.o: $(SRC_PATH)/version.rc config-host.mak > @@ -154,6 +178,7 @@ clean: > rm -f slirp/*.o slirp/*.d audio/*.o audio/*.d block/*.o block/*.d net/*.o net/*.d fsdev/*.o fsdev/*.d ui/*.o ui/*.d > rm -f qemu-img-cmds.h > rm -f trace.c trace.h trace.c-timestamp trace.h-timestamp > + rm -f trace-dtrace.dtrace trace-dtrace.h trace-dtrace.h-timestamp qemu.stp > $(MAKE) -C tests clean > for d in $(ALL_SUBDIRS) libhw32 libhw64 libuser libdis libdis-user; do \ > if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \ > @@ -214,6 +239,12 @@ ifneq ($(BLOBS),) > $(INSTALL_DATA) $(SRC_PATH)/pc-bios/$$x "$(DESTDIR)$(datadir)"; \ > done > endif > +ifeq ($(TRACE_BACKEND),dtrace) > +ifdef CONFIG_LINUX > + $(INSTALL_DIR) "$(DESTDIR)$(datadir)/../systemtap/tapset" > + $(INSTALL_DATA) qemu.stp "$(DESTDIR)$(datadir)/../systemtap/tapset" > +endif > +endif > $(INSTALL_DIR) "$(DESTDIR)$(datadir)/keymaps" > set -e; for x in $(KEYMAPS); do \ > $(INSTALL_DATA) $(SRC_PATH)/pc-bios/keymaps/$$x "$(DESTDIR)$(datadir)/keymaps"; \ > diff --git a/Makefile.objs b/Makefile.objs > index 816194a..ccecda0 100644 > --- a/Makefile.objs > +++ b/Makefile.objs > @@ -273,10 +273,14 @@ libdis-$(CONFIG_SPARC_DIS) += sparc-dis.o > ###################################################################### > # trace > > +ifeq ($(TRACE_BACKEND),dtrace) > +trace-obj-y = trace-dtrace.o > +else > trace-obj-y = trace.o > ifeq ($(TRACE_BACKEND),simple) > trace-obj-y += simpletrace.o > endif > +endif > > vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS) > > diff --git a/tracetool b/tracetool > index 7010858..59b66fd 100755 > --- a/tracetool > +++ b/tracetool > @@ -20,10 +20,13 @@ Backends: > --nop Tracing disabled > --simple Simple built-in backend > --ust LTTng User Space Tracing backend > + --dtrace DTrace/SystemTAP backend > > Output formats: > -h Generate .h file > -c Generate .c file > + -d Generate .d file (DTrace only) > + -s Generate .stp file (DTrace with SystemTAP only) > EOF > exit 1 > } > @@ -68,6 +71,31 @@ get_argnames() > fi > } > > +# Get the argument name list of a trace event > +get_arglist() The only difference between get_arglist() and get_argnames() is the comma added on the end of each argument name. Please reuse get_argnames() instead of duplicating it. One solution is to pass the argument separator as a string into get_argnames(). Passing '"' would produce the existing behavior and passing "" would produce the get_arglist() behavior that you need. > +{ > + local nfields field name > + nfields=0 > + for field in $(get_args "$1"); do > + nfields=$((nfields + 1)) > + > + # Drop pointer star > + field=${field#\*} > + > + # Only argument names have commas at the end > + name=${field%,} > + test "$field" = "$name" && continue > + > + printf "%s" "$name " > + done > + > + # Last argument name > + if [ "$nfields" -gt 1 ] > + then > + printf "%s" "$name" > + fi > +} > + > # Get the number of arguments to a trace event > get_argc() > { > @@ -306,6 +334,127 @@ EOF > echo "}" > } > > +linetoh_begin_dtrace() > +{ > + cat <<EOF > +#include "trace-dtrace.h" > +EOF > +} > + > +linetoh_dtrace() > +{ > + local name args state Missing argnames and nameupper. > + name=$(get_name "$1") > + args=$(get_args "$1") > + argnames=$(get_argnames "$1") > + state=$(get_state "$1") > + if [ "$state" = "0" ] ; then > + name=${name##disable } > + fi > + > + nameupper=`echo $name | tr '[:lower:]' '[:upper:]'` > + > + # Define an empty function for the trace event > + cat <<EOF > +static inline void trace_$name($args) { > + if (QEMU_${nameupper}_ENABLED()) > + QEMU_${nameupper}($argnames); > +} Please follow QEMU coding style even for generated code. 4 space indentation and curly braces for all if statements: static inline void trace_$name($args) { if (QEMU_${nameupper}_ENABLED()) { QEMU_${nameupper}($argnames); } } > +EOF > +} > + > +linetoh_end_dtrace() > +{ > + return > +} > + > +linetoc_begin_dtrace() > +{ > + return > +} > + > +linetoc_dtrace() > +{ > + # No need for function definitions in dtrace backend > + return > +} > + > +linetoc_end_dtrace() > +{ > + return > +} > + > +linetod_begin_dtrace() > +{ > + cat <<EOF > +provider qemu { > +EOF > +} > + > +linetod_dtrace() > +{ > + local name args state > + name=$(get_name "$1") > + args=$(get_args "$1") > + state=$(get_state "$1") > + if [ "$state" = "0" ] ; then > + name=${name##disable } > + fi > + > + # Define prototype for probe arguments > + cat <<EOF > + probe $name($args); > +EOF > +} > + > +linetod_end_dtrace() > +{ > + cat <<EOF > +}; > +EOF > +} > + > +linetos_begin_dtrace() > +{ > + return > +} > + > +linetos_dtrace() > +{ > + local name args argnames state Missing arglist. argnames is unused. > + name=$(get_name "$1") > + args=$(get_args "$1") > + arglist=$(get_arglist "$1") > + state=$(get_state "$1") > + if [ "$state" = "0" ] ; then > + name=${name##disable } > + fi > + > + # Define prototype for probe arguments > + cat <<EOF > +probe qemu.$name = process("qemu").mark("$name") > +{ > +EOF > + > + i=1 > + for arg in $arglist > + do > + cat <<EOF > + $arg = \$arg$i; > +EOF > + i="$((i+1))" > + done > + > + cat <<EOF > +} > +EOF > +} > + > +linetos_end_dtrace() > +{ > + return > +} > + > # Process stdin by calling begin, line, and end functions for the backend > convert() > { > @@ -326,7 +475,7 @@ convert() > if test -z "$disable"; then > # Pass the disabled state as an arg to lineto$1_simple(). This comment is not outdated. Please update it or change it so the backend is not explicitly named. Stefan
Please also add dtrace to the ./configure --help output: echo " --trace-backend=B Trace backend nop simple ust dtrace" Stefan
On Wed, Oct 20, 2010 at 02:50:12PM +0100, Stefan Hajnoczi wrote: > Please also add dtrace to the ./configure --help output: > > echo " --trace-backend=B Trace backend nop simple ust dtrace" I've just sent a v2 that should include all your feedback so far. Regards, Daniel
diff --git a/.gitignore b/.gitignore index a43e4d1..0d27afd 100644 --- a/.gitignore +++ b/.gitignore @@ -4,6 +4,9 @@ config-host.* config-target.* trace.h trace.c +trace-dtrace.h +trace-dtrace.dtrace +qemu.stp *-timestamp *-softmmu *-darwin-user diff --git a/Makefile b/Makefile index 252c817..812b0d3 100644 --- a/Makefile +++ b/Makefile @@ -1,6 +1,9 @@ # Makefile for QEMU. GENERATED_HEADERS = config-host.h trace.h +ifeq ($(TRACE_BACKEND),dtrace) +GENERATED_HEADERS += trace-dtrace.h +endif ifneq ($(wildcard config-host.mak),) # Put the all: rule here so that config-host.mak can contain dependencies. @@ -106,7 +109,11 @@ ui/vnc.o: QEMU_CFLAGS += $(VNC_TLS_CFLAGS) bt-host.o: QEMU_CFLAGS += $(BLUEZ_CFLAGS) +ifeq ($(TRACE_BACKEND),dtrace) +trace.h: trace.h-timestamp trace-dtrace.h +else trace.h: trace.h-timestamp +endif trace.h-timestamp: $(SRC_PATH)/trace-events config-host.mak $(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -h < $< > $@," GEN trace.h") @cmp -s $@ trace.h || cp $@ trace.h @@ -118,6 +125,23 @@ trace.c-timestamp: $(SRC_PATH)/trace-events config-host.mak trace.o: trace.c $(GENERATED_HEADERS) +trace-dtrace.h: trace-dtrace.dtrace + $(call quiet-command,dtrace -o $@ -h -s $<, " GEN trace-dtrace.h") + +# Normal practice is to name DTrace probe file with a '.d' extension +# but that gets picked up by QEMU's Makefile as an external dependancy +# rule file. So we use '.dtrace' instead +trace-dtrace.dtrace: trace-dtrace.dtrace-timestamp +trace-dtrace.dtrace-timestamp: $(SRC_PATH)/trace-events config-host.mak + $(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -d < $< > $@," GEN trace-dtrace.dtrace") + @cmp -s $@ trace-dtrace.dtrace || cp $@ trace-dtrace.dtrace +ifdef CONFIG_LINUX + $(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -s < $< > qemu.stp," GEN qemu.stp") +endif + +trace-dtrace.o: trace-dtrace.dtrace $(GENERATED_HEADERS) + $(call quiet-command,dtrace -o $@ -G -s $<, " GEN trace-dtrace.o") + simpletrace.o: simpletrace.c $(GENERATED_HEADERS) version.o: $(SRC_PATH)/version.rc config-host.mak @@ -154,6 +178,7 @@ clean: rm -f slirp/*.o slirp/*.d audio/*.o audio/*.d block/*.o block/*.d net/*.o net/*.d fsdev/*.o fsdev/*.d ui/*.o ui/*.d rm -f qemu-img-cmds.h rm -f trace.c trace.h trace.c-timestamp trace.h-timestamp + rm -f trace-dtrace.dtrace trace-dtrace.h trace-dtrace.h-timestamp qemu.stp $(MAKE) -C tests clean for d in $(ALL_SUBDIRS) libhw32 libhw64 libuser libdis libdis-user; do \ if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \ @@ -214,6 +239,12 @@ ifneq ($(BLOBS),) $(INSTALL_DATA) $(SRC_PATH)/pc-bios/$$x "$(DESTDIR)$(datadir)"; \ done endif +ifeq ($(TRACE_BACKEND),dtrace) +ifdef CONFIG_LINUX + $(INSTALL_DIR) "$(DESTDIR)$(datadir)/../systemtap/tapset" + $(INSTALL_DATA) qemu.stp "$(DESTDIR)$(datadir)/../systemtap/tapset" +endif +endif $(INSTALL_DIR) "$(DESTDIR)$(datadir)/keymaps" set -e; for x in $(KEYMAPS); do \ $(INSTALL_DATA) $(SRC_PATH)/pc-bios/keymaps/$$x "$(DESTDIR)$(datadir)/keymaps"; \ diff --git a/Makefile.objs b/Makefile.objs index 816194a..ccecda0 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -273,10 +273,14 @@ libdis-$(CONFIG_SPARC_DIS) += sparc-dis.o ###################################################################### # trace +ifeq ($(TRACE_BACKEND),dtrace) +trace-obj-y = trace-dtrace.o +else trace-obj-y = trace.o ifeq ($(TRACE_BACKEND),simple) trace-obj-y += simpletrace.o endif +endif vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS) diff --git a/tracetool b/tracetool index 7010858..59b66fd 100755 --- a/tracetool +++ b/tracetool @@ -20,10 +20,13 @@ Backends: --nop Tracing disabled --simple Simple built-in backend --ust LTTng User Space Tracing backend + --dtrace DTrace/SystemTAP backend Output formats: -h Generate .h file -c Generate .c file + -d Generate .d file (DTrace only) + -s Generate .stp file (DTrace with SystemTAP only) EOF exit 1 } @@ -68,6 +71,31 @@ get_argnames() fi } +# Get the argument name list of a trace event +get_arglist() +{ + local nfields field name + nfields=0 + for field in $(get_args "$1"); do + nfields=$((nfields + 1)) + + # Drop pointer star + field=${field#\*} + + # Only argument names have commas at the end + name=${field%,} + test "$field" = "$name" && continue + + printf "%s" "$name " + done + + # Last argument name + if [ "$nfields" -gt 1 ] + then + printf "%s" "$name" + fi +} + # Get the number of arguments to a trace event get_argc() { @@ -306,6 +334,127 @@ EOF echo "}" } +linetoh_begin_dtrace() +{ + cat <<EOF +#include "trace-dtrace.h" +EOF +} + +linetoh_dtrace() +{ + local name args state + name=$(get_name "$1") + args=$(get_args "$1") + argnames=$(get_argnames "$1") + state=$(get_state "$1") + if [ "$state" = "0" ] ; then + name=${name##disable } + fi + + nameupper=`echo $name | tr '[:lower:]' '[:upper:]'` + + # Define an empty function for the trace event + cat <<EOF +static inline void trace_$name($args) { + if (QEMU_${nameupper}_ENABLED()) + QEMU_${nameupper}($argnames); +} +EOF +} + +linetoh_end_dtrace() +{ + return +} + +linetoc_begin_dtrace() +{ + return +} + +linetoc_dtrace() +{ + # No need for function definitions in dtrace backend + return +} + +linetoc_end_dtrace() +{ + return +} + +linetod_begin_dtrace() +{ + cat <<EOF +provider qemu { +EOF +} + +linetod_dtrace() +{ + local name args state + name=$(get_name "$1") + args=$(get_args "$1") + state=$(get_state "$1") + if [ "$state" = "0" ] ; then + name=${name##disable } + fi + + # Define prototype for probe arguments + cat <<EOF + probe $name($args); +EOF +} + +linetod_end_dtrace() +{ + cat <<EOF +}; +EOF +} + +linetos_begin_dtrace() +{ + return +} + +linetos_dtrace() +{ + local name args argnames state + name=$(get_name "$1") + args=$(get_args "$1") + arglist=$(get_arglist "$1") + state=$(get_state "$1") + if [ "$state" = "0" ] ; then + name=${name##disable } + fi + + # Define prototype for probe arguments + cat <<EOF +probe qemu.$name = process("qemu").mark("$name") +{ +EOF + + i=1 + for arg in $arglist + do + cat <<EOF + $arg = \$arg$i; +EOF + i="$((i+1))" + done + + cat <<EOF +} +EOF +} + +linetos_end_dtrace() +{ + return +} + # Process stdin by calling begin, line, and end functions for the backend convert() { @@ -326,7 +475,7 @@ convert() if test -z "$disable"; then # Pass the disabled state as an arg to lineto$1_simple(). # For all other cases, call lineto$1_nop() - if [ $backend = "simple" ]; then + if [ $backend = "simple" -o "$backend" = "dtrace" ]; then "$process_line" "$str" else "lineto$1_nop" "${str##disable }" @@ -360,9 +509,29 @@ tracetoc() convert c } +tracetod() +{ + if [ $backend != "dtrace" ]; then + echo "DTrace probe generator not applicable to $backend backend" + exit 1 + fi + echo "/* This file is autogenerated by tracetool, do not edit. */" + convert d +} + +tracetos() +{ + if [ $backend != "dtrace" ]; then + echo "SystemTAP tapset generator not applicable to $backend backend" + exit 1 + fi + echo "/* This file is autogenerated by tracetool, do not edit. */" + convert s +} + # Choose backend case "$1" in -"--nop" | "--simple" | "--ust") backend="${1#--}" ;; +"--nop" | "--simple" | "--ust" | "--dtrace") backend="${1#--}" ;; *) usage ;; esac shift @@ -370,6 +539,8 @@ shift case "$1" in "-h") tracetoh ;; "-c") tracetoc ;; +"-d") tracetod ;; +"-s") tracetos ;; "--check-backend") exit 0 ;; # used by ./configure to test for backend *) usage ;; esac
This introduces a new tracing backend that targets the SystemTAP implementation of DTrace userspace tracing. The core functionality should be applicable and standard across any DTrace implementation on Solaris, OS-X, *BSD, but the Makefile rules will likely need some small additional changes to cope with OS specific build requirements. This backend builds a little differently from the other tracing backends. Specifically there is no 'trace.c' file, because the 'dtrace' command line tool generates a '.o' file directly from the dtrace probe definition file. The probe definition is usually named with a '.d' extension but QEMU uses '.d' files for its external makefile dependancy tracking, so this uses '.dtrace' as the extension for the probe definition file. The 'tracetool' program gains the ability to generate a trace.h file for DTrace, and also to generate the trace.d file containing the dtrace probe definition, and finally a qemu.stp file which is a wrapper around the probe definition providing more convenient access from SystemTAP scripts. eg, instead of probe process("qemu").mark("qemu_malloc") { printf("Malloc %d %p\n", $arg1, $arg2); } The addition of qemu.stp to /usr/share/systemtap/tapset/ lets users write probe qemu.qemu_malloc { printf("Malloc %d %p\n", size, ptr); } * .gitignore: Ignore trace-dtrace.* * Makefile: Extra rules for generating DTrace files * Makefile.obj: Don't build trace.o for DTrace, use trace-dtrace.o generated by 'dtrace' instead * tracetool: Support for generating DTrace/SystemTAP data files Signed-off-by: Daniel P. Berrange <berrange@redhat.com> --- .gitignore | 3 + Makefile | 31 ++++++++++ Makefile.objs | 4 + tracetool | 175 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 4 files changed, 211 insertions(+), 2 deletions(-)