----- On Jul 15, 2020, at 2:28 PM, rostedt rostedt@xxxxxxxxxxx wrote: > On Wed, 15 Jul 2020 20:37:16 +0430 > ahmadkhorrami <ahmadkhorrami@xxxxxxxx> wrote: > >> Hi, >> What is the most efficient way to capture occurrence of a function >> call/return of a binary program in userspace? >> It seems the answer is Uprobes. 1) Am I right? >> But Uprobes use "int" instruction which leads to a switch into kernel >> mode. 2) Wouldn't it be better to avoid this transition? >> I'm looking forward to your reply and will be happy to read your >> opinions. >> Regards. > > > Hi, I believe LTTng has utilities that can help you trace user space > programs. Indeed, it is documented here: https://lttng.org/docs/#doc-liblttng-ust-cyg-profile If your program is generating function entry/exit at a very high rate (which goes beyond your available I/O throughput and lasts longer than the memory you have available for ring buffers), you will also probably want to use the "blocking-timeout" option documented at: https://lttng.org/docs/#doc-enabling-disabling-channels Thanks, Mathieu > > I think there's also a users ftrace like utility that Namhyung was > working on. But I don't know where in the development that is. > > -- Steve -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com
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