----- Original Message ----- > From: "Paul Woegerer" <[email protected]> > To: [email protected], "mathieu desnoyers" > <[email protected]> > Sent: Thursday, July 10, 2014 8:49:37 AM > Subject: Ping: Re: [PATCH lttng-ust] Bugfix for > http://bugs.lttng.org/issues/745 > > Hi Mathieu, > > Since we have no other options currently (see LD_AUDIT discussion) we > really should get this merged into master. As said, it's thoroughly > tested and should not cause any ill side-effects.
Hi Paul, Sorry about the delayed answer, I was busy implementing a tool that extracts UST buffers in the event of a system crash. Looking at your patch below, I wonder why you use a semaphore (0, 1) rather than a mutex ? I guess you could achieve the same result with a pthread mutex ? If so, it would be better, because it makes it easier to understand mutex nesting. Thanks, Mathieu > > Many Thanks, > Paul > > On 07/04/2014 02:21 PM, Paul Woegerer wrote: > > Since (at least) in the short term LD_AUDIT will not be able to make > > sem_wait() > > in the static constructor go away I provide the following patch to fix > > http://bugs.lttng.org/issues/745. > > > > It works by making the process of forking mutual exclusive with base > > address > > statedumping that happens from the ust_listener_thread. > > > > I have tested this fix with several variations of (constrained) fork bombs > > (including tests/regression/ust/daemon from lttng-tools) on x86_64, > > ARM(imx6q) > > and powerpc(P4080DS). It works reliable. I could not find any issues with > > this > > approach. > > > > Paul Woegerer (1): > > Bugfix for #745 deadlock with baddr statedump+fork > > > > liblttng-ust/lttng-ust-comm.c | 21 +++++++++++++++++++++ > > 1 file changed, 21 insertions(+) > > > > > -- > Paul Woegerer, SW Development Engineer > Sourcery Analyzer <http://go.mentor.com/sourceryanalyzer> > Mentor Graphics, Embedded Software Division > -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
