Re: [Valgrind-users] Enabling instrumentation with callgrind_control not working

[Christian P. <chr...@gm...>]

2015-02-01 20:54 GMT+00:00 Philippe Waroquiers <
phi...@sk...>:

> On Sun, 2015-02-01 at 20:39 +0000, Christian Priebe wrote:
>
> >
> > It unfortunately does not work. I receive the following message:
> >
> > "vgdb error: no FIFO found matching pid 5803"
> >
> >
> > "5803" is the pid as reported by vgdb -l.
>
> can you do
>     vgdb -d -d -d -l
> and then
>     vgdb -d -d -d --pid=12345 help
> (assuming 12345 is the pid of the mysql process).
> That should give detailed tracing about which FIFOs are found
> and/or tried by both vgdb commands.
>
> Note that you have to run vgdb in a context
> which is similar to the context of the process you
> are trying to contact.
> Typically, TMPDIR and the user launching vgdb must be the same
> as TMPDIR value and user of the process you are trying to contact.
>

Thanks! I actualy made a mistake and ran mysqld under a different user. I'm
back to the previous issue that callgrind_control or more specifically vgdb
hangs. This is the output I get when running vgdb -d -d -d -pid=...
instrumentation on I get the following output:

1422830987.435580 vgdb: using
/tmp/vgdb-pipe-from-vgdb-to-7052-by-root-on-???
/tmp/vgdb-pipe-to-vgdb-from-7052-by-root-on-???
/tmp/vgdb-pipe-shared-mem-vgdb-7052-by-root-on-???
1422830987.435677 opening /tmp/vgdb-pipe-from-vgdb-to-7052-by-root-on-???
write to pid
1422830987.435720 written_by_vgdb_before_sleep 0
seen_by_valgrind_before_sleep 0
1422830987.435720 opened /tmp/vgdb-pipe-from-vgdb-to-7052-by-root-on-???
write to pid fd 4
1422830987.435796 writing write \003 to wake up len 1  notify: 1
1422830987.435811 opening /tmp/vgdb-pipe-to-vgdb-from-7052-by-root-on-???
read cmd result from pid
1422830987.536904 written_by_vgdb_before_sleep 1
seen_by_valgrind_before_sleep 0
1422830987.638022 after sleep written_by_vgdb 1 seen_by_valgrind 0
invoked_written -1
1422830987.638111 attach to 'main' pid 7052
1422830987.638153 attach main pid PTRACE_ATTACH pid 7052
1422830987.638428 waitstopped attach main pid before waitpid
signal_expected 19
1422830987.638704 after waitpid pid 7052 p 7052 status 0x137f WIFSTOPPED 19
1422830987.639102 found tid 1 status VgTs_WaitSys lwpid 7052
...
1422830987.645251 getregs regs_bsz 216
1422830987.645275 getregs PTRACE_GETREGS
1422830987.645289 detected a working PTRACE_GETREGS
1422830987.645302 push bad_return return address ptrace_write_memory
1422830987.645315 Writing 0000000000000000 to 0x804390d18
1422830987.645395 setregs regs_bsz 216
1422830987.645409 setregs PTRACE_SETREGS
1422830987.645424 PTRACE_CONT to invoke
1422830987.645461 waitstopped waitpid status after PTRACE_CONT to invoke
before waitpid signal_expected 19

and then it stops doing anything.


Thanks,
Christian



>
> Philippe
>
>
>
>
>