Re: missing data in traces

* Jan Altenberg ([email protected]) wrote:
> 
> > Confirmation that it works fine for you would be appreciated :)
> 
> Still seems to crash on my system.
> 

Hi Pierre-Marc,

This one seems to be caused by your new code that does not mix well with
irq/trap/softirq tables resize while the trace is read.

soft_irq_states
irq_states
trap_states

should be updated upon

softirq_entry
irq_entry
trap_entry

and

dump_softirq
(dump irq and dump traps not implemented yet)

A function that dynamically updates the name and state table sizes when
required should be created.

(that also includes syscall_entry and dump_syscalls)

My current code that looks like

  if (unlikely(ts->nb_irqs <= irq)) {
    /* Fixup an incomplete irq table */
    GQuark *old_names = ts->irq_names;
    guint new_nb_irqs = max(irq + 1, ts->nb_irqs * 2);
    guint i;
    GString *fe_name = g_string_new("");
    ts->irq_names = g_new(GQuark, new_nb_irqs);
    memcpy(ts->irq_names, old_names,
        ts->nb_irqs * sizeof(GQuark));
    for(i = ts->nb_irqs ; i < new_nb_irqs ; i++) {
      g_string_printf(fe_name, "irq %d", i);
      ts->irq_names[i] = g_quark_from_string(fe_name->str);
    }
    g_string_free(fe_name, TRUE);
    ts->nb_irqs = new_nb_irqs;
  }

(that's the irq example) should be put in this function, along with
syscall, softirq and traps table size updates, and with the *_states
size updates too.

Can you find time to look into this ?

Mathieu


> Program received signal SIGSEGV, Segmentation fault.
> 0x000000000041482a in irq_entry (hook_data=<value optimized out>, call_data=<value optimized out>)
>     at state.c:1981
> 1981      g_array_set_size(irqst->mode_stack, irqst->mode_stack->len + 1);
> (gdb) bt
> #0  0x000000000041482a in irq_entry (hook_data=<value optimized out>, call_data=<value optimized out>)
>     at state.c:1981
> #1  0x000000000040c90f in lttv_hooks_call_merge (h1=0x7d8c60, call_data1=0x8d4550, h2=0x95cb00, 
>     call_data2=0x8d4550) at hook.c:333
> #2  0x0000000000418cb3 in lttv_process_traceset_middle (self=0x82fb40, end=
>       {tv_sec = 12338, tv_nsec = 982591959}, nb_events=6000, end_position=0x0) at tracecontext.c:768
> #3  0x00002b2bf998a166 in execute_events_requests (tab=0x7e3060) at callbacks.c:1446
> #4  0x00000034eb02cf64 in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
> #5  0x00000034eb02fd9d in g_main_context_check () from /lib64/libglib-2.0.so.0
> #6  0x00000034eb0300aa in g_main_loop_run () from /lib64/libglib-2.0.so.0
> #7  0x0000003c56f2dad3 in gtk_main () from /usr/lib64/libgtk-x11-2.0.so.0
> #8  0x00002b2bf99867a6 in window_creation_hook (hook_data=<value optimized out>, 
>     call_data=<value optimized out>) at init_module.c:129
> #9  0x000000000040c9aa in lttv_hooks_call (h=0x62bf40, call_data=0x0) at hook.c:272
> #10 0x000000000040af3d in main (argc=15, argv=0x7fffb158aa88) at main.c:219
> 
> 	Jan
> 

-- 
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68