Re: libpfm4 faults on P4 machine

[stephane eranian <eranian@googlemail.com>]

Lin,

It should not have chosen  intel_x86_arch to begin with.
That's where the bug is. Let me fix this.


On Wed, Aug 18, 2010 at 9:46 AM, Lin Ming <ming.m.lin@intel.com> wrote:
> On P4 machine, intel_x86_arch_support.get_event_info(...) faults because
> intel_x86_arch_support.pe is NULL.
>
> intel_x86_arch_support.pe is set at run time, but P4 does not have arch
> event support, so intel_x86_arch_support.pe is always NULL.
>
> #gdb libpfm4/examples/check_events
>
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 0xb785caf0 (LWP 3950)]
> 0x0804d74b in pfm_intel_x86_get_event_info (this=0x81c5f80, idx=0, info=0xbff45f14)
>    at pfmlib_intel_x86.c:667
> 667             info->desc  = pe[idx].desc;
> (gdb) bt
> #0  0x0804d74b in pfm_intel_x86_get_event_info (this=0x81c5f80, idx=0, info=0xbff45f14)
>    at pfmlib_intel_x86.c:667
> #1  0x08049cd3 in pfmlib_parse_event (event=0x804fb7b "PERF_COUNT_HW_CPU_CYCLES", d=0xbff45f7c)
>    at pfmlib_common.c:676
> #2  0x08049f3f in pfm_get_event_encoding (str=0x804fb7b "PERF_COUNT_HW_CPU_CYCLES", dfl_plm=8,
>    fstr=0xbff464d4, idx=0xbff464c8, codes=0xbff464d0, count=0xbff464cc) at pfmlib_common.c:877
> #3  0x08048dc1 in main (argc=<value optimized out>, argv=0xbff46584) at check_events.c:118
> (gdb) list
> 662
> 663             /*
> 664              * pmu and idx filled out by caller
> 665              */
> 666             info->name  = pe[idx].name;
> 667             info->desc  = pe[idx].desc;
> 668             info->code  = pe[idx].code;
> 669             info->equiv = pe[idx].equiv;
> 670
> 671             /* unit masks + modifiers */
> (gdb)
>
> Any fix?
>
> Lin Ming
>
>