Re: [PATCH] perf_events: fix errors path in perf_output_begin()

From: Stephane Eranian
Date: Mon May 17 2010 - 08:23:24 EST


On Mon, May 17, 2010 at 2:09 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> On Mon, 2010-05-17 at 14:04 +0200, Stephane Eranian wrote:
>>
>> > So you want to preserve this state for when you munmap() and mmap()
>> > again? The only user of data->lost is writing the PERF_RECORD_LOST
>> > event, which only ever happens when you have pages, so counting it when
>> > there's no pages seems futile.
>>
>> You're right. But couldn't you report lost samples in the buffer header as well?
>
> I guess you could, but what's the point? If you ask for sampling but
> don't provide a buffer you don't get anything -- how's that a surprise?
>
Fine. I'll update the patch to not account for data->lost.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/