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tools lib traceevent: Export dynamic symbols used by traceevent plugins

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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 <hekuang@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1432819735-35040-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
He Kuang 2015-05-28 13:28:54 +00:00 committed by Arnaldo Carvalho de Melo
parent f87027b968
commit e3d09ec812
2 changed files with 25 additions and 3 deletions
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14
tools/lib/traceevent/Makefile
View File

@ -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
@ -157,8 +158,9 @@ 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)
@ -175,6 +177,9 @@ $(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 $@)
@ -244,6 +249,13 @@ 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),$(libdir_SQ))

14
tools/perf/Makefile.perf
View File

@ -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)
@ -555,4 +564,5 @@ 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