Traceevent plugins need dynamic symbols exported from libtraceevent.a,
otherwise a dlopen error will occur during plugins loading.
This patch uses dynamic-list-file to export dynamic symbols which will
be used in plugins to perf executable.
The problem is covered up if feature-libpython is enabled, because
PYTHON_EMBED_LDOPTS contains '-Xlinker --export-dynamic' which adds all
symbols to the dynamic symbol table. So we should reproduce the problem
by setting NO_LIBPYTHON=1.
Before this patch:
(Prepare plugins)
$ ls /root/.traceevent/plugins/
plugin_sched_switch.so
plugin_function.so
...
$ perf record -e 'ftrace:function' ls
$ perf script
Warning: could not load plugin '/mnt/data/root/.traceevent/plugins/plugin_sched_switch.so'
/root/.traceevent/plugins/plugin_sched_switch.so: undefined symbol: pevent_unregister_event_handler
Warning: could not load plugin '/root/.traceevent/plugins/plugin_function.so'
/root/.traceevent/plugins/plugin_function.so: undefined symbol: warning
...
:1049 1049 [000] 9666.754487: ftrace:function: ffffffff8118bc50 <-- ffffffff8118c5b3
:1049 1049 [000] 9666.754487: ftrace:function: ffffffff818e2440 <-- ffffffff8118bc75
:1049 1049 [000] 9666.754487: ftrace:function: ffffffff8106eee0 <-- ffffffff811212e2
After this patch:
$ perf record -e 'ftrace:function' ls
$ perf script
:1049 1049 [000] 9666.754487: ftrace:function: __set_task_comm
:1049 1049 [000] 9666.754487: ftrace:function: _raw_spin_lock
:1049 1049 [000] 9666.754487: ftrace:function: task_tgid_nr_ns
...
Signed-off-by: He Kuang <[email protected]>
---
tools/lib/traceevent/Makefile | 14 +++++++++++++-
tools/perf/Makefile.perf | 9 +++++++--
2 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/tools/lib/traceevent/Makefile b/tools/lib/traceevent/Makefile
index d410da3..2cbac13 100644
--- a/tools/lib/traceevent/Makefile
+++ b/tools/lib/traceevent/Makefile
@@ -23,6 +23,7 @@ endef
# Allow setting CC and AR, or setting CROSS_COMPILE as a prefix.
$(call allow-override,CC,$(CROSS_COMPILE)gcc)
$(call allow-override,AR,$(CROSS_COMPILE)ar)
+$(call allow-override,NM,$(CROSS_COMPILE)nm)
EXT = -std=gnu99
INSTALL = install
@@ -151,8 +152,9 @@ PLUGINS_IN := $(PLUGINS:.so=-in.o)
TE_IN := $(OUTPUT)libtraceevent-in.o
LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
+DYNAMIC_LIST_FILE := $(OUTPUT)libtraceevent-dynamic-list
-CMD_TARGETS = $(LIB_FILE) $(PLUGINS)
+CMD_TARGETS = $(LIB_FILE) $(PLUGINS) $(DYNAMIC_LIST_FILE)
TARGETS = $(CMD_TARGETS)
@@ -169,6 +171,9 @@ $(OUTPUT)libtraceevent.so: $(TE_IN)
$(OUTPUT)libtraceevent.a: $(TE_IN)
$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
+$(OUTPUT)libtraceevent-dynamic-list: $(PLUGINS)
+ $(QUIET_GEN)$(call do_generate_dynamic_list_file, $(PLUGINS), $@)
+
plugins: $(PLUGINS)
__plugin_obj = $(notdir $@)
@@ -238,6 +243,13 @@ define do_install_plugins
done
endef
+define do_generate_dynamic_list_file
+ (echo '{'; \
+ $(NM) -u -D $1 | awk 'NF>1 {print "\t"$$2";"}' | sort -u; \
+ echo '};'; \
+ ) > $2
+endef
+
install_lib: all_cmd install_plugins
$(call QUIET_INSTALL, $(LIB_FILE)) \
$(call do_install,$(LIB_FILE),$(bindir_SQ))
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 03409cc..19c61e0 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -172,6 +172,7 @@ endif
LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
export LIBTRACEEVENT
+LIBTRACEEVENT_DYNAMIC_LIST = $(TE_PATH)libtraceevent-dynamic-list
LIBAPI = $(LIB_PATH)libapi.a
export LIBAPI
@@ -278,8 +279,9 @@ build := -f $(srctree)/tools/build/Makefile.build dir=. obj
$(PERF_IN): $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h FORCE
$(Q)$(MAKE) $(build)=perf
-$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN)
- $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(PERF_IN) $(LIBS) -o $@
+LD_LIBTRACEEVENT_FLAGS += -Xlinker --dynamic-list=$(LIBTRACEEVENT_DYNAMIC_LIST)
+$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN) $(LIBTRACEEVENT_DYNAMIC_LIST)
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(LD_LIBTRACEEVENT_FLAGS) $(PERF_IN) $(LIBS) -o $@
$(GTK_IN): FORCE
$(Q)$(MAKE) $(build)=gtk
@@ -375,6 +377,9 @@ LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)
$(LIBTRACEEVENT): FORCE
$(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a plugins
+$(LIBTRACEEVENT_DYNAMIC_LIST): $(LIBTRACEEVENT)
+ $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent-dynamic-list
+
$(LIBTRACEEVENT)-clean:
$(call QUIET_CLEAN, libtraceevent)
$(Q)$(MAKE) -C $(TRACE_EVENT_DIR) O=$(OUTPUT) clean >/dev/null
--
1.8.5.2
The libtrace-dynamic-list file is used to export symbols used by
traceevent plugins.
Signed-off-by: He Kuang <[email protected]>
---
tools/lib/traceevent/.gitignore | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/lib/traceevent/.gitignore b/tools/lib/traceevent/.gitignore
index 35f56be..3c60335 100644
--- a/tools/lib/traceevent/.gitignore
+++ b/tools/lib/traceevent/.gitignore
@@ -1 +1,2 @@
TRACEEVENT-CFLAGS
+libtraceevent-dynamic-list
--
1.8.5.2
On Mon, May 11, 2015 at 09:35:26AM +0000, He Kuang wrote:
> Traceevent plugins need dynamic symbols exported from libtraceevent.a,
> otherwise a dlopen error will occur during plugins loading.
>
> This patch uses dynamic-list-file to export dynamic symbols which will
> be used in plugins to perf executable.
>
> The problem is covered up if feature-libpython is enabled, because
> PYTHON_EMBED_LDOPTS contains '-Xlinker --export-dynamic' which adds all
> symbols to the dynamic symbol table. So we should reproduce the problem
> by setting NO_LIBPYTHON=1.
there's was another patch taking the shortcut:
http://marc.info/?l=linux-kernel&m=142885447432384&w=2
it seems it's not merged yet, but I like this one better
SNIP
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 03409cc..19c61e0 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -172,6 +172,7 @@ endif
>
> LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
> export LIBTRACEEVENT
> +LIBTRACEEVENT_DYNAMIC_LIST = $(TE_PATH)libtraceevent-dynamic-list
>
> LIBAPI = $(LIB_PATH)libapi.a
> export LIBAPI
> @@ -278,8 +279,9 @@ build := -f $(srctree)/tools/build/Makefile.build dir=. obj
> $(PERF_IN): $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h FORCE
> $(Q)$(MAKE) $(build)=perf
>
> -$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN)
> - $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(PERF_IN) $(LIBS) -o $@
> +LD_LIBTRACEEVENT_FLAGS += -Xlinker --dynamic-list=$(LIBTRACEEVENT_DYNAMIC_LIST)
> +$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN) $(LIBTRACEEVENT_DYNAMIC_LIST)
> + $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(LD_LIBTRACEEVENT_FLAGS) $(PERF_IN) $(LIBS) -o $@
>
> $(GTK_IN): FORCE
> $(Q)$(MAKE) $(build)=gtk
> @@ -375,6 +377,9 @@ LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)
> $(LIBTRACEEVENT): FORCE
> $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a plugins
>
> +$(LIBTRACEEVENT_DYNAMIC_LIST): $(LIBTRACEEVENT)
> + $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent-dynamic-list
hum, do we need extra target in Makefile.perf, it could be rebuilt any time
'plugins:' target in lib/tracevent/Makefile is called
jirka
Em Mon, May 11, 2015 at 04:33:09PM +0200, Jiri Olsa escreveu:
> On Mon, May 11, 2015 at 09:35:26AM +0000, He Kuang wrote:
> > Traceevent plugins need dynamic symbols exported from libtraceevent.a,
> > otherwise a dlopen error will occur during plugins loading.
> >
> > This patch uses dynamic-list-file to export dynamic symbols which will
> > be used in plugins to perf executable.
> >
> > The problem is covered up if feature-libpython is enabled, because
> > PYTHON_EMBED_LDOPTS contains '-Xlinker --export-dynamic' which adds all
> > symbols to the dynamic symbol table. So we should reproduce the problem
> > by setting NO_LIBPYTHON=1.
>
> there's was another patch taking the shortcut:
> http://marc.info/?l=linux-kernel&m=142885447432384&w=2
>
> it seems it's not merged yet, but I like this one better
Ok, please let me know when something that can be merged is ready,
- Arnaldo
> SNIP
>
>
> > diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> > index 03409cc..19c61e0 100644
> > --- a/tools/perf/Makefile.perf
> > +++ b/tools/perf/Makefile.perf
> > @@ -172,6 +172,7 @@ endif
> >
> > LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
> > export LIBTRACEEVENT
> > +LIBTRACEEVENT_DYNAMIC_LIST = $(TE_PATH)libtraceevent-dynamic-list
> >
> > LIBAPI = $(LIB_PATH)libapi.a
> > export LIBAPI
> > @@ -278,8 +279,9 @@ build := -f $(srctree)/tools/build/Makefile.build dir=. obj
> > $(PERF_IN): $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h FORCE
> > $(Q)$(MAKE) $(build)=perf
> >
> > -$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN)
> > - $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(PERF_IN) $(LIBS) -o $@
> > +LD_LIBTRACEEVENT_FLAGS += -Xlinker --dynamic-list=$(LIBTRACEEVENT_DYNAMIC_LIST)
> > +$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN) $(LIBTRACEEVENT_DYNAMIC_LIST)
> > + $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(LD_LIBTRACEEVENT_FLAGS) $(PERF_IN) $(LIBS) -o $@
> >
> > $(GTK_IN): FORCE
> > $(Q)$(MAKE) $(build)=gtk
> > @@ -375,6 +377,9 @@ LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)
> > $(LIBTRACEEVENT): FORCE
> > $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a plugins
> >
> > +$(LIBTRACEEVENT_DYNAMIC_LIST): $(LIBTRACEEVENT)
> > + $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent-dynamic-list
>
> hum, do we need extra target in Makefile.perf, it could be rebuilt any time
> 'plugins:' target in lib/tracevent/Makefile is called
>
> jirka
On 11 May 2015 at 16:33, Jiri Olsa <[email protected]> wrote:
> On Mon, May 11, 2015 at 09:35:26AM +0000, He Kuang wrote:
>> Traceevent plugins need dynamic symbols exported from libtraceevent.a,
>> otherwise a dlopen error will occur during plugins loading.
>>
>> This patch uses dynamic-list-file to export dynamic symbols which will
>> be used in plugins to perf executable.
>>
>> The problem is covered up if feature-libpython is enabled, because
>> PYTHON_EMBED_LDOPTS contains '-Xlinker --export-dynamic' which adds all
>> symbols to the dynamic symbol table. So we should reproduce the problem
>> by setting NO_LIBPYTHON=1.
>
> there's was another patch taking the shortcut:
> http://marc.info/?l=linux-kernel&m=142885447432384&w=2
>
> it seems it's not merged yet, but I like this one better
>
I don't care much as long as it get fixed -- either using the big
hammer with -Wl,--export-dynamic or the fine grained approach using a
symbol file.
Thanks,
Mathias
Hi, jirka
On 2015/5/11 22:33, Jiri Olsa wrote:
> On Mon, May 11, 2015 at 09:35:26AM +0000, He Kuang wrote:
>> Traceevent plugins need dynamic symbols exported from libtraceevent.a,
>> otherwise a dlopen error will occur during plugins loading.
>>
>> This patch uses dynamic-list-file to export dynamic symbols which will
>> be used in plugins to perf executable.
>>
>> The problem is covered up if feature-libpython is enabled, because
>> PYTHON_EMBED_LDOPTS contains '-Xlinker --export-dynamic' which adds all
>> symbols to the dynamic symbol table. So we should reproduce the problem
>> by setting NO_LIBPYTHON=1.
> there's was another patch taking the shortcut:
> http://marc.info/?l=linux-kernel&m=142885447432384&w=2
>
> it seems it's not merged yet, but I like this one better
>
> SNIP
>
>
>> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
>> index 03409cc..19c61e0 100644
>> --- a/tools/perf/Makefile.perf
>> +++ b/tools/perf/Makefile.perf
>> @@ -172,6 +172,7 @@ endif
>>
>> LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
>> export LIBTRACEEVENT
>> +LIBTRACEEVENT_DYNAMIC_LIST = $(TE_PATH)libtraceevent-dynamic-list
>>
>> LIBAPI = $(LIB_PATH)libapi.a
>> export LIBAPI
>> @@ -278,8 +279,9 @@ build := -f $(srctree)/tools/build/Makefile.build dir=. obj
>> $(PERF_IN): $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h FORCE
>> $(Q)$(MAKE) $(build)=perf
>>
>> -$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN)
>> - $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(PERF_IN) $(LIBS) -o $@
>> +LD_LIBTRACEEVENT_FLAGS += -Xlinker --dynamic-list=$(LIBTRACEEVENT_DYNAMIC_LIST)
>> +$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN) $(LIBTRACEEVENT_DYNAMIC_LIST)
>> + $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(LD_LIBTRACEEVENT_FLAGS) $(PERF_IN) $(LIBS) -o $@
>>
>> $(GTK_IN): FORCE
>> $(Q)$(MAKE) $(build)=gtk
>> @@ -375,6 +377,9 @@ LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)
>> $(LIBTRACEEVENT): FORCE
>> $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a plugins
>>
>> +$(LIBTRACEEVENT_DYNAMIC_LIST): $(LIBTRACEEVENT)
>> + $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent-dynamic-list
> hum, do we need extra target in Makefile.perf, it could be rebuilt any time
> 'plugins:' target in lib/tracevent/Makefile is called
>
> jirka
Yes, the dynamic-list-file should be rebuilt when plugins
changed, and not depends on $(LIBTRACEEVENT).
I sent a new version, please review that patch.
$ touch ../lib/traceevent/plugin_function.c
$ make
CC plugin_function.o
LD plugin_function-in.o
LINK plugin_function.so
GEN libtraceevent-dynamic-list
LINK perf
Thanks.