Hi, (2013/10/07 15:46), Hemant Kumar wrote: > This patchset helps in probing dtrace style markers(SDT) present in user space > applications through perf. Notes/markes are placed at important places by the > developers. They have a negligible overhead when not enabled. We can enable > them and probe at these places and find some important information like the > arguments' values, etc.
Thank you for updating! By the way, could you rebase this series to the latest -tip kernel next time? It is more convenient for us to test & merge it. [...] > - Now use perf to list the markers in the app: > # perf probe --markers -x ./user_app > > %user_app:foo_start > %user_app:fun_start Here, what I got. $ ./perf probe --markers -x /lib64/librt.so %librt:lll_futex_wake OK, it lists up markers. $ ./perf probe --markers -x ./perf SDT markers not present! Error : Failed to find SDT markers!(-1) OK, this shows an error, INHO, it'd better show which binary doesn't have markers. $ ./perf probe --markers Failed to open (null) Error : Failed to find SDT markers!(-1) Hmm, it's a bit odd error. It should check if there is an elf binary is specified. $ ./perf probe --markers /lib64/librt.so %librt:lll_futex_wake It seems to work without -x. However, that is only when the path is started with /. And also the usage is not described by --help. $ ./perf probe --markers ./perf Semantic error :File always requires line number or lazy pattern. Error: Parse Error. (-22) So, to avoid confusion, --markers should abort without -x(--exec) option. > - And then use perf probe to add a probe point : > > # perf probe -x ./user_app -a '%user_app:foo_start' And also, without -x, -a also exits with an odd error message. $ ./perf probe -a %libm:slowexp_p6 Failed to open (null) Error: Failed to add events. (-1) I'll review each patch soon. 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/
