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Date: Tue, 05 Sep 2017 12:58:22 +0200
From: Andreas Longwitz <longwitz@incore.de>
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Subject: dtrace pid provider on entry == Trace/BPT trap process
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I use FreeBSD 10.3-STABLE r317936 with updated /usr/lib/dtrace/ip.c and
see an issue that in my opinion should have been solved in r269342:

I run a simple program looptest, that loops around a sprintf() call and
want to check this program with

dtrace -n 'pid$target:libc.so.*::entry {@[probefunc] = count();}' -p
$(pgrep looptest)
dtrace: description 'pid$target:libc.so.*::entry ' matched 3863 probes

After some seconds I hit CTRL-C and see

  __vfprintf                                                   741685
  localeconv_l                                                 741685
  memset                                                       741685
  sprintf                                                      741685
  vsprintf                                                     741685
  __sfvwrite                                                  1483369
  memcpy                                                      2225052

and at the same time looptest stops with
   Trace/BPT trap (Speicherabzug geschrieben)
and on the console I see the kernel message
   pid 67550 (looptest), uid 1003: exited on signal 5 (core dumped)

The trap does not occur all the time, but it is no problem to repeat the
trap.


---
Andreas Longwitz