I have an experimental prototype where you can evaluate any Perl expression
from mdb. For example:
> ::walk proc | ::peval 'mdb_printf("%p\n", $_) if ($_ > 0x30100000000)' | ::ps
S PID PPID PGID SID UID FLAGS ADDR NAME
R 7081 25390 7081 1277 0 0x00004008 0000030136c7cba8 sh
R 19508 18010 19508 1277 0 0x00004008 0000030109b2e188 mdb
R 19534 2605 19534 498 78440 0x00014008 0000030136c7d5c0 man
R 19541 19540 19534 498 78440 0x00004008 0000030136c7c190 less
R 14686 609 14686 14686 78440 0x00004008 0000030109b2f5b8 cam
R 14708 14686 14686 14686 78440 0x00004008 0000030109b3cb98 acroread
Z 14757 14708 14686 14686 0 0x10006008 0000030109b3c180 lp
This filter process address greater than 0x30100000000.
You can also access types as Perl objects and thus use any Perl expression to
access their data:
> ::peval '$d = mdb_ctf_readvar("devnamesp") ; mdb_printf("dn_name = %x\n",
> $d->{dn_flags} & 0x2)'
dn_name = 2
Or you can write Perl script, for example test.pl:
sub thread
{
my $addr = shift;
my $t, $p, $cmd;
$t = new CTF::pointer kthread_t, $addr;
$p = $t->{t_procp};
$cmd = $p->{p_user}{u_comm};
mdb_printf "%p %hd %p %s\n", $t, $t->{t_pri}, $p, mdb_readstr($cmd);
}
and then invoke it from mdb:
> t0::pcall thread
140a000 96 14382d8 sched
But this is just early experiments and it still often crash mdb :-).
alex.
Jonathan Adams wrote:
> On Wed, Oct 12, 2005 at 07:49:01PM +0100, Frank Hofmann - Solaris Sustaining
> wrote:
>
>>Btw, is there an existing RFE against mdb asking to be able to
>>use "::offsetof" and "::sizeof" in arithmetic expressions, to
>>get better array handling support ?
>>
>>I.e. I'd like to look at specific elements of arrays, something
>>like:
>>
>>*devnamesp+(20*::sizeof(struct devnames))::print struct devnames
>>
>>Or better: "*devnamesp[20]::print struct devnames", with typegraph
>>help :)
>
>
> You can just do:
>
>
>>devnamesp::print [20]
>
> {
> [20].dn_name = 0xffffffff82a46ba0 "hci1394"
> ...
> }
>
>
> The main thing that has been talked about is '::deval', '::dmap', or
> '::dprint', which would let you use D (as in Dtrace) expressions. It
> might look something like:
>
>
>>::dprint '`devnamesp[20]->dn_flags & 0x100'
>
> 0x100
>
>
> Cheers,
> - jonathan
>
