Re: [patch] Re: [perf] Finding uninstalled modules Was Re: mailing list for trace users

[Avi Kivity <avi@redhat.com>]

On 09/23/2009 04:50 PM, Mike Galbraith wrote:
> On Wed, 2009-09-23 at 16:10 +0300, Avi Kivity wrote:
>    
>> On 09/23/2009 03:58 PM, Avi Kivity wrote:On 09/23/2009 03:58 PM, Avi
>> Kivity wrote:
>>      
>>> Not for me.  'perf report', for example, shows
>>>
>>>      63.08%  qemu-system-x86
>>> [kernel]                                              [k] packet_exit
>>>       4.71%  qemu-system-x86
>>> [kernel]                                              [k] hpet_next_event
>>>       4.38%             init
>>> [kernel]                                              [k]
>>> mwait_idle_with_hints
>>>
>>> While 'perf top' still shows vmx_vcpu_run.
>>>
>>>        
>> strace says:
>>
>>      getcwd("/home/avi/kvm/linux-2.6"..., 4096) = 24
>>      ...
>>      [no chdir]
>>      ...
>>      open("kernel/arch/x86/kvm/kvm-intel.ko", O_RDONLY) = -1 ENOENT (No
>> such file or directory)
>>      
> *blink*
>
>    
>> That "kernel/" looks like it was meant for /lib/modules, not a kernel
>> tree.  If I run 'perf report' from /lib/modules/2.6.31 I see vmx_vcpu_run.
>>      
> So I need what's in your modules.dep to figure out where the rest of the
> path went.
>
>    

Mine says:

   kernel/arch/x86/kvm/kvm.ko:
   kernel/arch/x86/kvm/kvm-intel.ko: kernel/arch/x86/kvm/kvm.ko

Which is reasonable for /lib/modules/2.6.31, not for a source directory.

> /lib/modules/2.6.32-tip-smp/kernel/arch/x86/kvm/kvm-intel.ko
>
> static int mod_dso__load_module_paths(struct mod_dso *self)
> {
>          struct utsname uts;
>          int count = 0, len;
>          char *line = NULL;
>          FILE *file;
>          char *path;
>          size_t n;
>
>          if (uname(&uts)<  0)
>                  goto out_failure;
>
>          len = strlen("/lib/modules/");
>          len += strlen(uts.release);
>          len += strlen("/modules.dep");
>
>          path = calloc(1, len);
>    

len + 1

>          if (path == NULL)
>                  goto out_failure;
>
>          strcat(path, "/lib/modules/");
>          strcat(path, uts.release);
>          strcat(path, "/modules.dep");
>
>          file = fopen(path, "r");
>
>    

-- 
error compiling committee.c: too many arguments to function