2015-05-15 08:13:41

by He Kuang

[permalink] [raw]
Subject: [PATCH v3 1/2] tools lib traceevent: Export dynamic symbols used by traceevent plugins

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 | 14 ++++++++++++--
2 files changed, 25 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..1e6e038 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -173,6 +173,9 @@ endif
LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
export LIBTRACEEVENT

+LIBTRACEEVENT_DYNAMIC_LIST = $(TE_PATH)libtraceevent-dynamic-list
+LDFLAGS += -Xlinker --dynamic-list=$(LIBTRACEEVENT_DYNAMIC_LIST)
+
LIBAPI = $(LIB_PATH)libapi.a
export LIBAPI

@@ -278,7 +281,7 @@ 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) $(PERF_IN)
+$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN) $(LIBTRACEEVENT_DYNAMIC_LIST)
$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(PERF_IN) $(LIBS) -o $@

$(GTK_IN): FORCE
@@ -373,7 +376,13 @@ $(LIB_FILE): $(LIBPERF_IN)
LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)

$(LIBTRACEEVENT): FORCE
- $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a plugins
+ $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a
+
+libtraceevent_plugins: FORCE
+ $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) plugins
+
+$(LIBTRACEEVENT_DYNAMIC_LIST): libtraceevent_plugins
+ $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent-dynamic-list

$(LIBTRACEEVENT)-clean:
$(call QUIET_CLEAN, libtraceevent)
@@ -551,4 +560,5 @@ FORCE:
.PHONY: all install clean config-clean strip install-gtk
.PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell
.PHONY: $(GIT-HEAD-PHONY) TAGS tags cscope FORCE single_dep
+.PHONY: libtraceevent_plugins

--
1.8.5.2


2015-05-15 08:12:13

by He Kuang

[permalink] [raw]
Subject: [PATCH v3 2/2] tools lib traceevent: Ignore libtrace-dynamic-list file

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

2015-05-24 08:30:52

by He Kuang

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] tools lib traceevent: Export dynamic symbols used by traceevent plugins

hi, jirka

ping..

Thanks.

On 2015/5/15 16:01, 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.
>
> 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 | 14 ++++++++++++--
> 2 files changed, 25 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..1e6e038 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -173,6 +173,9 @@ endif
> LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
> export LIBTRACEEVENT
>
> +LIBTRACEEVENT_DYNAMIC_LIST = $(TE_PATH)libtraceevent-dynamic-list
> +LDFLAGS += -Xlinker --dynamic-list=$(LIBTRACEEVENT_DYNAMIC_LIST)
> +
> LIBAPI = $(LIB_PATH)libapi.a
> export LIBAPI
>
> @@ -278,7 +281,7 @@ 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) $(PERF_IN)
> +$(OUTPUT)perf: $(PERFLIBS) $(PERF_IN) $(LIBTRACEEVENT_DYNAMIC_LIST)
> $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(PERF_IN) $(LIBS) -o $@
>
> $(GTK_IN): FORCE
> @@ -373,7 +376,13 @@ $(LIB_FILE): $(LIBPERF_IN)
> LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)
>
> $(LIBTRACEEVENT): FORCE
> - $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a plugins
> + $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent.a
> +
> +libtraceevent_plugins: FORCE
> + $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) plugins
> +
> +$(LIBTRACEEVENT_DYNAMIC_LIST): libtraceevent_plugins
> + $(Q)$(MAKE) -C $(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) O=$(OUTPUT) $(OUTPUT)libtraceevent-dynamic-list
>
> $(LIBTRACEEVENT)-clean:
> $(call QUIET_CLEAN, libtraceevent)
> @@ -551,4 +560,5 @@ FORCE:
> .PHONY: all install clean config-clean strip install-gtk
> .PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell
> .PHONY: $(GIT-HEAD-PHONY) TAGS tags cscope FORCE single_dep
> +.PHONY: libtraceevent_plugins
>
>

2015-05-24 18:50:26

by Jiri Olsa

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] tools lib traceevent: Export dynamic symbols used by traceevent plugins

On Fri, May 15, 2015 at 08:01:18AM +0000, He Kuang wrote:

SNIP

> :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]>

sorry for the delay..

Acked-by: Jiri Olsa <[email protected]>

thanks,
jirka