From: He Kuang Date: Thu, 28 May 2015 13:28:54 +0000 (+0000) Subject: tools lib traceevent: Export dynamic symbols used by traceevent plugins X-Git-Tag: omap-for-v4.3/legacy-v2-signed~210^2~3^2~5 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3d09ec8126fe2c9a3ade661e2126e215ca27a80;p=pandora-kernel.git 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 Acked-by: Jiri Olsa Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1432819735-35040-1-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- Reading git-diff-tree failed