On 06/26, Steven Rostedt wrote: > > [ Added Oleg who is the guru of signals ;-) ]
Thanks, I didn't see the patch, so I can only guess what it does, > On Thu, 26 Jun 2014 09:57:21 -0400 > Christopher Covington <[email protected]> wrote: > > > This stops a process after an event has been triggered a given > > number of times. For example: > > > > [[ -d /sys/kernel/debug/tracing ]] || \ > > mount -t debugfs none /sys/kernel/debug > > echo "p:myevent $(which myapp):0x700" > > > /sys/kernel/debug/tracing/uprobe_events > > echo 1 > /sys/kernel/debug/tracing/events/uprobes/myevent/enable > > echo 'signal:3' > /sys/kernel/debug/tracing/events/uprobes/myevent/trigger > > myapp > > myapp > > myapp & > > > > Here, the 0x700 offset is the entry to main(). On the third > > invocation of the program, the process is stopped. > > > > Interesting trigger. I can see this being useful. Yes. I thought about this too. > > +//ifdef CONFIG_TRACER_SIGNAL > > +static void > > +signal_trigger(struct event_trigger_data *data) > > +{ > > + force_sig(SIGSTOP, current); Well, I don't like this. Imho, it would be nice to avoid signals here. And SIGSTOP in particular. It can interfere with the "real" SIGSTOP sent by user, with ptrace, with tty. I think we need something else... "STOP" is actually simple, but we need some interface which allows to wakeup a task sleeping in TASK_KILLABLE after it hits ETT_FREEZE. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
