Re: [PATCH] perf test shell: Fix check open filename arg using 'perf trace'

[Hendrik Brueckner <brueckner@linux.vnet.ibm.com>]

Hi Arnaldo,

On Thu, Nov 30, 2017 at 01:59:22PM -0200, Arnaldo de Melo wrote:
> Em Thu, Nov 30, 2017 at 01:56:42PM -0200, Arnaldo de Melo escreveu:
> > Em Thu, Nov 30, 2017 at 11:28:33AM +0100, Thomas-Mich Richter escreveu:
> > > On 11/29/2017 06:27 PM, Michael Petlan wrote:
> > [acme@jouet linux]$ git log -1 27702bcfe8a125a1feeeb5f07526d63b20cac47f --oneline
> > 27702bcfe8a1 perf trace: Support syscall name globbing
> > [acme@jouet linux]$
> > 
> > Is in v4.14 final.
> > 
> > Testing with/without those quotes:
> > 
> > [root@jouet ~]# perf trace -e open* touch /etc/passwd
> >      0.000 ( 0.007 ms): touch/17246 open(filename: 0x99747e37, flags: CLOEXEC                             ) = 3
> >      0.022 ( 0.004 ms): touch/17246 open(filename: 0x9994b640, flags: CLOEXEC                             ) = 3
> >      0.189 ( 0.004 ms): touch/17246 open(filename: 0x994f1c70, flags: CLOEXEC                             ) = 3
> >      0.224 ( 0.056 ms): touch/17246 open(filename: 0xaa80a32a, flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: IRUGO|IWUGO) = 3
> > [root@jouet ~]# perf trace -e 'open*' touch /etc/passwd
> >      0.000 ( 0.039 ms): touch/17250 open(filename: 0xf1445e37, flags: CLOEXEC                             ) = 3
> >      0.107 ( 0.030 ms): touch/17250 open(filename: 0xf1649640, flags: CLOEXEC                             ) = 3
> >      0.976 ( 0.009 ms): touch/17250 open(filename: 0xf11efc70, flags: CLOEXEC                             ) = 3
> >      1.032 ( 0.008 ms): touch/17250 open(filename: 0x9357432a, flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: IRUGO|IWUGO) = 3
> > [root@jouet ~]#
> > 
> > What differs from x86 to others is that x86 uses syscalltbl, not requiring
> > audit-libs to map syscall numbers to names, so perhaps it is something in there...
> 
> Yeah :-\
> 
> int syscalltbl__strglobmatch_next(struct syscalltbl *tbl __maybe_unused,
>                                   const char *syscall_glob __maybe_unused, int *idx __maybe_unused)
> {
>         return -1;
> }
> 
> int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char
> *syscall_glob, int *idx)
> {
>         return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
> }
> #endif /* HAVE_SYSCALL_TABLE */
> 
> -----
> 
> So someone needs to implement syscalltbl__strglobmatch_next() for arches
> that don't HAVE_SYSCALL_TABLE, which is basically at this stage !x86.
> 
> Shouldn't be that difficult, but remains to be done.

Thanks for pointing in that direction.  I looked at it and will post a
patch to add syscall tables for s390 too.

Kind regards,
  Hendrik