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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi folks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m studying how to use Lttng now. I built a kernel which version is 2.6.38 and ran with lttng 2.0.<o:p></o:p></p><p class=MsoNormal>I got some confused when I started to use it. Here are my questions:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>1. I didn’t see kernel patches for kernel 3.x. Does it mean kernel 3.x support it already? <o:p></o:p></p><p class=MsoNormal>2. I tried to do something like, dump the arguments of system call, or dump a backtrace in a specified function. But the output of lttng is very limited. Is there a way to do that with lttng?<o:p></o:p></p><p class=MsoNormal>3. I looked into some UST examples and found here are three header files: tracepoint.h, tracepoint-event.h and ust-tracepoint-event.h. They have some duplicated macro definitions like TRACEPOINT_EVENT.<o:p></o:p></p><p class=MsoNormal>And the examples includes all of these three header files despite no conflict here. Could someone help to explain the intention?<o:p></o:p></p><p class=MsoNormal>4. Once I defined a tracepoint in my code, seems some initializations would register default probe into the hook point. How to disable the default probe and register my self-defined probes?<o:p></o:p></p><p class=MsoNormal>5. Does lttng-ust support dynamic traceing like kprobe?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m a newbie of lttng. Any help will be appreciated.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks<o:p></o:p></p><p class=MsoNormal>Zheng<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>