[erlang-questions] Segfault in NIF call
Fredrik Linder
fredrik@REDACTED
Mon Jul 29 23:43:22 CEST 2013
I just realized I never got back on this.
Thank you for your help :-)
I ended up re-writing it using a TDD approach, only took a few hours to get
everything working again
/Fredrik
On Tue, Apr 30, 2013 at 6:13 AM, Greg Burd <greg@REDACTED> wrote:
> Are you trying to build a NIF where the function is run on a
> non-Erlang scheduler thread (async, via some thread pool)? If so,
> here's a method for doing it.
>
> https://gist.github.com/gburd/4121795
>
> It took a while to get this just right, reuse and enjoy. I'll update
> the nifwait (https://github.com/basho/nifwait) repo with example code.
> The best example of how to use it is in the wterl
> (https://github.com/basho-labs/wterl) repo.
>
> -greg
>
> @gregburd | Basho Technologies | Riak | http://basho.com | @basho
>
>
> On Mon, Apr 29, 2013 at 2:57 PM, Fredrik Linder <fredrik@REDACTED>
> wrote:
> > Found one error (yay!) -- enif_open_resource_type should have NULL as the
> > module argument (missed this one in the docs)
> >
> > Running with cerl does not generate a segfault, nor any (extra) printouts
> > Running with erl still generate segfault
> >
> > Now I get either of the following (using erl), does it reveal what my
> error
> > is?
> >
> >> USE_GDB=1 rebar eunit
> > [cut]
> > Program received signal SIGSEGV, Segmentation fault.
> > [Switching to Thread 0x2aaaad6c0700 (LWP 6384)]
> > 0x000000000052b28a in process_main () at
> > x86_64-unknown-linux-gnu/opt/smp/beam_hot.h:979
> > 979 MoveDeallocateReturn(xb(tmp_packed1&BEAM_LOOSE_MASK), r(0),
> > Qb((tmp_packed1>>BEAM_LOOSE_SHIFT)));
> > (gdb) backtrace
> > #0 0x000000000052b28a in process_main () at
> > x86_64-unknown-linux-gnu/opt/smp/beam_hot.h:979
> > #1 0x0000000000491463 in sched_thread_func (vesdp=0x2aaaac343ac0) at
> > beam/erl_process.c:5632
> > #2 0x0000000000590440 in thr_wrapper (vtwd=0x7fffffffd850) at
> > pthread/ethread.c:106
> > #3 0x00002aaaab3ffe9a in start_thread (arg=0x2aaaad6c0700) at
> > pthread_create.c:308
> > #4 0x00002aaaab911cbd in clone () at
> > ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
> > #5 0x0000000000000000 in ?? ()
> >
> > or
> >
> > Program received signal SIGSEGV, Segmentation fault.
> > [Switching to Thread 0x2aaaad6c0700 (LWP 6914)]
> > unlink_free_block (allctr=0x85e5c0, block=0x0, flags=0) at
> > beam/erl_goodfit_alloc.c:458
> > 458 Uint sz = MBC_FBLK_SZ(&blk->block_head);
> > (gdb) backtrace
> > #0 unlink_free_block (allctr=0x85e5c0, block=0x0, flags=0) at
> > beam/erl_goodfit_alloc.c:458
> > #1 0x0000000000444ee1 in get_free_block (allctr=0x85e5c0,
> size=<optimized
> > out>, cand_blk=0x0, cand_size=0, flags=0) at beam/erl_goodfit_alloc.c:426
> > #2 0x000000000043b6da in mbc_alloc_block (alcu_flgsp=<synthetic
> pointer>,
> > blk_szp=<synthetic pointer>, size=<optimized out>, allctr=0x85e5c0) at
> > beam/erl_alloc_util.c:1309
> > #3 mbc_alloc (allctr=0x85e5c0, size=<optimized out>) at
> > beam/erl_alloc_util.c:1451
> > #4 0x0000000000440d7b in do_erts_alcu_alloc (size=32, extra=0x85e5c0,
> > type=148) at beam/erl_alloc_util.c:3530
> > #5 erts_alcu_alloc_thr_pref (type=148, extra=<optimized out>,
> > size=<optimized out>) at beam/erl_alloc_util.c:3607
> > #6 0x0000000000490595 in erts_alloc (size=32, type=18967) at
> > beam/erl_alloc.h:208
> > #7 new_message_buffer (size=0) at beam/erl_message.c:72
> > #8 erts_alloc_message_heap_state (statep=0x2aaaad6bfc4c,
> > receiver_locks=0x2aaaad6bfcb0, receiver=0x2aaaac9c1db8, ohpp=<synthetic
> > pointer>, bpp=<synthetic pointer>, size=0) at beam/global.h:1017
> > #9 erts_send_message (sender=0x2aaaac9c2470, receiver=0x2aaaac9c1db8,
> > receiver_locks=0x2aaaad6bfcb0, message=564171, flags=<optimized out>) at
> > beam/erl_message.c:1039
> > #10 0x0000000000476350 in do_send (p=0x2aaaac9c2470, to=793099,
> msg=564171,
> > suspend=1, refp=<optimized out>) at beam/bif.c:2025
> > #11 0x0000000000476bf0 in erl_send (p=0x2aaaac9c2470, to=793099,
> msg=564171)
> > at beam/bif.c:2138
> > #12 0x000000000052d1d8 in process_main () at beam/beam_emu.c:2558
> > #13 0x0000000000491463 in sched_thread_func (vesdp=0x2aaaac343ac0) at
> > beam/erl_process.c:5632
> > #14 0x0000000000590440 in thr_wrapper (vtwd=0x7fffffffd850) at
> > pthread/ethread.c:106
> > #15 0x00002aaaab3ffe9a in start_thread (arg=0x2aaaad6c0700) at
> > pthread_create.c:308
> > #16 0x00002aaaab911cbd in clone () at
> > ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
> > #17 0x0000000000000000 in ?? ()
> >
> >
> > /Fredrik
> >
> >
> >
> >
> >
> >
> > On Mon, Apr 29, 2013 at 2:58 AM, Sverker Eriksson
> > <sverker.eriksson@REDACTED> wrote:
> >>
> >> Looks like some sort of memory corruption.
> >>
> >> Run on debug emulator and hope for a better (earlier) crash.
> >>
> >> # cd $ERL_TOP/erts/emulator
> >> # make TYPE=debug smp plain
> >> # $ERL_TOP/bin/cerl -debug
> >>
> >> /Sverker, Erlang/OTP Ericsson
> >>
> >> fredrik@REDACTED wrote:
> >>>
> >>> Hello folks,
> >>>
> >>> I'm having difficulties locating the cause of a segfault I'm getting
> when
> >>> running tests with a NIF implementation I have.
> >>>
> >>> Anything that would shed light on what's wrong is appreciated.
> >>>
> >>> The backtrace does not seem to have anything to do with my NIF. The
> >>> NIF:ed function is called from a few different processes, and it
> forwards
> >>> the call to a worker thread which sends a message back to the caller
> >>> process.
> >>>
> >>>
> >>>>
> >>>> strings -a
> >>>
> >>>
> >>>
> ../../otp/R16B/pre-5.10.1-mz-0.2/lib/erlang/erts-5.10.1/bin/beam.smp|fgrep
> >>> GCC|sort -u
> >>> GCC: (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3
> >>>
> >>>
> >>>>
> >>>> USE_GDB=1 rebar eunit
> >>>>
> >>>
> >>> [cut]
> >>> Program received signal SIGSEGV, Segmentation fault.
> >>> [Switching to Thread 0x2aaaef381700 (LWP 19162)]
> >>> unlink_free_block (allctr=0x85f240, block=0x0, flags=0) at
> >>> beam/erl_goodfit_alloc.c:458
> >>> 458 Uint sz = MBC_FBLK_SZ(&blk->block_head);
> >>> (gdb) backtrace
> >>> #0 unlink_free_block (allctr=0x85f240, block=0x0, flags=0) at
> >>> beam/erl_goodfit_alloc.c:458
> >>> #1 0x0000000000444ee1 in get_free_block (allctr=0x85f240,
> >>> size=<optimized out>, cand_blk=0x0, cand_size=0, flags=0) at
> >>> beam/erl_goodfit_alloc.c:426
> >>> #2 0x000000000043b6da in mbc_alloc_block (alcu_flgsp=<synthetic
> >>> pointer>, blk_szp=<synthetic pointer>, size=<optimized out>,
> >>> allctr=0x85f240) at beam/erl_alloc_util.c:1309
> >>> #3 mbc_alloc (allctr=0x85f240, size=<optimized out>) at
> >>> beam/erl_alloc_util.c:1451
> >>> #4 0x0000000000440d7b in do_erts_alcu_alloc (size=32, extra=0x85f240,
> >>> type=148) at beam/erl_alloc_util.c:3530
> >>> #5 erts_alcu_alloc_thr_pref (type=148, extra=<optimized out>,
> >>> size=<optimized out>) at beam/erl_alloc_util.c:3607
> >>> #6 0x0000000000490595 in erts_alloc (size=32, type=18967) at
> >>> beam/erl_alloc.h:208
> >>> #7 new_message_buffer (size=0) at beam/erl_message.c:72
> >>> #8 erts_alloc_message_heap_state (statep=0x2aaaef380c4c,
> >>> receiver_locks=0x2aaaef380cb0, receiver=0x2aaaac9ccac8, ohpp=<synthetic
> >>> pointer>, bpp=<synthetic pointer>, size=0) at beam/global.h:1017
> >>> #9 erts_send_message (sender=0x2aaaac9cd118, receiver=0x2aaaac9ccac8,
> >>> receiver_locks=0x2aaaef380cb0, message=513931, flags=<optimized out>)
> at
> >>> beam/erl_message.c:1039
> >>> #10 0x0000000000476350 in do_send (p=0x2aaaac9cd118, to=550027,
> >>> msg=513931, suspend=1, refp=<optimized out>) at beam/bif.c:2025
> >>> #11 0x0000000000476bf0 in erl_send (p=0x2aaaac9cd118, to=550027,
> >>> msg=513931) at beam/bif.c:2138
> >>> #12 0x000000000052d1d8 in process_main () at beam/beam_emu.c:2558
> >>> #13 0x0000000000491463 in sched_thread_func (vesdp=0x2aaaac34de40) at
> >>> beam/erl_process.c:5632
> >>> #14 0x0000000000590440 in thr_wrapper (vtwd=0x7fffffffd7e0) at
> >>> pthread/ethread.c:106
> >>> #15 0x00002aaaab3ffe9a in start_thread (arg=0x2aaaef381700) at
> >>> pthread_create.c:308
> >>> #16 0x00002aaaab911cbd in clone () at
> >>> ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
> >>> #17 0x0000000000000000 in ?? ()
> >>> (gdb)
> >>>
> >>>
> >>>
> ------------------------------------------------------------------------
> >>>
> >>> _______________________________________________
> >>> erlang-questions mailing list
> >>> erlang-questions@REDACTED
> >>> http://erlang.org/mailman/listinfo/erlang-questions
> >>>
> >>
> >>
> >
> >
> > _______________________________________________
> > erlang-questions mailing list
> > erlang-questions@REDACTED
> > http://erlang.org/mailman/listinfo/erlang-questions
> >
>
--
http://whosawesome.com/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://erlang.org/pipermail/erlang-questions/attachments/20130729/7dd70101/attachment.htm>
More information about the erlang-questions
mailing list