Re: [PATCH] tracing: Create generic syscall TRACE_EVENTs

[Josh Stone <jistone@redhat.com>]

On 08/18/2009 06:32 PM, Li Zefan wrote:
> It would be much better to see a sample output of these TRACE_EVENTs,
> so we'll see the what's the output if a syscall has less than 6 args.
> 
> And I guess it should be "(%lx, %lx, ..., %lx)"? Otherwise I think we'll
> see some negative values.

Thanks, you're right -- the args should be unsigned long.  Whether they
are hex or decimal doesn't matter to me, but I guess that does make
pointers easier to spot.

Here's some output that I get on x86_64:

> # tail trace
>             tail-1106  [000] 113218.474657: syscall_enter: NR 2 (7f2d34dd38f0, 0, 7f2d35009010, 5, 4, ffffffffffffffb0)
> 
>             tail-1106  [000] 113218.474809: syscall_enter: NR 5 (3, 7f2d35009040, 7f2d35009040, 5, 4, ffffffffffffffb0)
> 
>             tail-1106  [000] 113218.474855: syscall_enter: NR 9 (0, 50d3ad0, 1, 2, 3, 0)
> 
>             tail-1106  [000] 113218.474946: syscall_enter: NR 3 (3, 7f2d2f9a0000, 5e22, 2, 3, 0)
> 
>             tail-1106  [000] 113218.475673: syscall_enter: NR 2 (7fff5e42a654, 0, 0, 7fff5e429600, 80, 3)

It's very raw indeed, but that's what Ingo asked for. :)  The extra args
show up as whatever happened to be in those registers.

Josh