On Fri, 15 Aug 2014 10:54:35 -0700 Brendan Gregg <brendan.d.gregg@xxxxxxxxx> wrote: > G'Day, > > Not sure this is the right place to send ftrace feature requests (or > if I should try to send patches instead), so please redirect me if > needed... > > Function profiling is great. Is there a way to filter by PID? > set_ftrace_pid doesn't seem to work: > > # echo nop > current_tracer > # echo $$ > set_ftrace_pid > # echo 0 > function_profile_enabled > # echo 1 > function_profile_enabled > # head trace_stat/function0 > Function Hit Time Avg > s^2 > -------- --- ---- --- > --- > ext4_evict_inode 358 501550.3 us > 1400.978 us 4247547 us > ext4_mark_inode_dirty 6951 92433.96 us 13.297 > us 2423567 us > ext4_reserve_inode_write 7738 86654.82 us 11.198 > us 711959.6 us > ext4_file_write_iter 348 81828.82 us > 235.140 us 971130.5 us > ext4_dirty_inode 1178 77598.27 us 65.872 > us 294410.3 us > ext4_da_write_end 348 76089.57 us > 218.648 us 966750.6 us > ext4_rename 357 40821.26 us > 114.345 us 160818.4 us > ext4_alloc_da_blocks 357 34260.99 us 95.969 > us 160912.0 us > > Is it possible that set_ftrace_pid could support function profiling? > Hmm, it should have worked. What kernel did you try it on. I just found out that there's a bug in the code that was added in 3.16 with function profiling. I'm working on fixing that now. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-trace-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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