(2013/12/02 23:52), David Ahern wrote: > On 12/1/13, 10:59 PM, Masami Hiramatsu wrote: >> (2013/12/02 9:07), David Ahern wrote: >>> When requesting a function from a userspace library the error message to >>> the user is less than helpful. e.g., >>> >>> perf probe -x /lib64/libpthread-2.14.90.so -a >>> 'lock_full=__pthread_mutex_lock_full' >>> no symbols found in /lib64/libpthread-2.14.90.so, maybe install a >>> debug package? >>> Failed to load map. >>> Error: Failed to add events. (-22) >>> >>> In this cae the symbol really does exist but is a local symbol which is >>> filtered: >>> >>> nm /lib64/libpthread-2.14.90.so | grep __pthread_mutex_lock_full >>> 0000000000005700 t __pthread_mutex_lock_full >>> >>> With this patch: >>> perf probe -x /lib64/libpthread-2.14.90.so -a >>> 'lock_full=__pthread_mutex_lock_full' >>> >>> no symbols found in /lib64/libpthread-2.14.90.so, maybe install a >>> debug package? >>> Failed to find function in /lib64/libpthread-2.14.90.so. Perhaps it is >>> a local variable? >> >> Hmm, indeed current message is too less information, but your message looks >> wired. I think just showing "Failed to find requested symbol in %s" is >> enough. :) > > I disagree. perf-probe filters non-global variables: > > if (sym->binding == STB_GLOBAL && > strfilter__compare(available_func_filter, sym->name)) > return 0; > > That needs to be explicitly stated in the error message -- only global > symbols may be given.
Ah, I see. In that case, I think the "variable" is not a correct word, the "symbol" is better, because perf probe can take tracing variable arguments after the trace point definition. :) Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu...@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
