On Wed, Apr 12, 2006 at 04:43:12PM +0800, Oliver Yang wrote:
> Jonathan Adams wrote:
>
> >On Tue, Apr 11, 2006 at 08:22:15AM +0800, Oliver Yang wrote:
> >
> >
> >>Sorry for raising the question again, maybe my question is not very
> >>clear...
> >>
> >>Actually, I need check the general register's value for a specific CPU
> >>on MP system. But, it seems like ::regs couldn't meet my requirement.
> >>Does anybody know the other way?
> >>
> >>
> >
> >Typically, you want to look at the trap frame on the active thread on the
> >CPU. I haven't done this on i386 in a while; can someone chime in with the
> >procedure?
> >
> >On sparc, you just take the active thread on the cpu, do a ::findstack on
> >it,
> >take the ktl0 frame address, and do:
> >
> > addr::print struct frame fr_local[7] | ::print struct regs
> >
> >
> Sorry. Thank you for your response, although I'm not familiar with sparc
> platform.
>
> I ask this question because sometimes ::findstack doesn't work for me on
> my crashdump file:
>
> > ::cpuinfo -v
> ID ADDR FLG NRUN BSPL PRI RNRN KRNRN SWITCH THREAD PROC
> 0 fec22eb4 1b 1 6 165 no no t-0 cb956de0 sched
> | | |
> RUNNING <--+ | +--> PIL THREAD
> READY | 6 cb956de0
> EXISTS |
> ENABLE +--> PRI THREAD PROC
> 0 cca2a600 rsh
>
> ID ADDR FLG NRUN BSPL PRI RNRN KRNRN SWITCH THREAD PROC
> 1 cc1449c0 1f 2 0 -1 no no t-0 cc2e6de0 sched
> | |
> RUNNING <--+ +--> PRI THREAD PROC
> READY 60 cba61de0 sched
> QUIESCED 60 cbaa7de0 sched
> EXISTS
> ENABLE
>
> > cb956de0::findstack
> stack pointer for thread cb956de0: cb956ab8
> cb956de0 0xcc9f7130()
> > cc2e6de0::findstack
> Possible stack pointers for thread cc2e6de0:
> cc2e6d00 (2)
> cc2e6d54 (2)
> cc2e6db8 (2)
> > cb956ab8,30/nap
>
>
> If ::findstack doesn't work, we have to check stack by stack pointer
> register (esp) on x86.
>
> But you know, ::regs just can output 1 cpu's register value, in above
> case, I couldn't get cpu 1 's register value.
As part of a panic, the panicking CPU cross-calls the other CPUs, inducing
them to call panic_idle(). In panic_idle(), the stack pointer is stored
in the thread's t_pcb field. Something like:
addr::print kthread_t t_pcb.value[1] | $C
(where addr is the active thread on the CPU) might get you a stack trace.
Cheers,
- jonathan
--
Jonathan Adams, Solaris Kernel Development
