----- On Apr 16, 2019, at 2:21 PM, Sebastien Boisvert sboisv...@gydle.com wrote:
> On 2019-04-16 2:12 p.m., Mathieu Desnoyers wrote: > [snip] >> >> Hi Sebastien, >> >> This part of the ring buffer should only be used by the consumer daemon >> through >> liblttng-ust-ctl.so, never from the traced applications. >> >> So I keep suspecting that it's NPTL's use of SIG33 which is causing an old >> version of gdb to trap, ref: >> https://gdb.sourceware.narkive.com/SzqG56iA/program-received-signal-sig33-real-time-event-33 >> >> Thanks, >> >> Mathieu >> > > If it is the case that an old gdb is involved, > then it is unrelated to this kill() call site in the LTTng-UST source code: > > libringbuffer/ring_buffer_frontend.c:767: kill(getpid(), > LTTNG_UST_RB_SIG_TEARDOWN); > > because LTTNG_UST_RB_SIG_TEARDOWN is SIGRTMIN + 2. According to the man page > of > signal(7) [1], > SIGRTMIN is 34 (Native Posix Thread Library) or 35 (LinuxThreads, whatever > that > is). > > > The equation > > 33 = SIGRTMIN + 2 > > is not satisfied with either 34 or 35. > > > So, is upgrading gdg the solution ? Based on the gdb forum link I showed, either explicitly disable handling SIG33 in older gdb: handle SIG33 nostop noprint pass or upgrade gdb. Thanks, Mathieu > > > [1] http://man7.org/linux/man-pages/man7/signal.7.html > > > [snip] -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
