Re: [PATCH v4 0/4] perf timechart io mode

From: Stanislav Fomichev
Date: Tue Jun 24 2014 - 12:57:32 EST


On Tue, Jun 24, 2014 at 01:10:22PM +0400, Stanislav Fomichev wrote:
> > hum, got this when trying:
> >
> > [jolsa@krava perf]$ sudo ./perf timechart record -I
> > ^C[ perf record: Woken up 2 times to write data ]
> > [ perf record: Captured and wrote 1.071 MB perf.data (~46806 samples) ]
> > [jolsa@krava perf]$ ./perf timechart
> > Invalid previous event (non-zero)!
> > 0x113f80 [0x8]: failed to process type: 68
> Hm, I added a bunch of consistency checks which I couldn't actually hit
> myself. Nice work :-) Can I get you perf.data?

For some reason, in Jiri's trace we see exit from sys_read with 2,
and then again exit from sys_read with -EAGAIN:
xterm 32028 [000] 43390.908909: syscalls:sys_enter_read: fd: 0x00000004, buf: 0x02076e8c, count: 0x0
xterm 32028 [000] 43390.908917: syscalls:sys_exit_read: 0x2
xterm 32028 [000] 43390.908982: syscalls:sys_exit_read: 0xfffffffffffffff5

I'm not sure how it is possible (either we lost sys_enter, or timestamp
of seconds -EAGAIN is wrong?). I think we might just convert this error
to a warning (we couldn't reproduce it again).
Should I resend the whole series (preferred) or add another patch on
top?
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