On 11/09/2024 09:14, Leo Yan wrote:

On 9/10/2024 9:28 PM, Leo Yan wrote:

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On 9/5/2024 11:50 AM, James Clark wrote:

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cs_etm__flush(), like cs_etm__sample() is an operation that generates a sample and then swaps the current with the previous packet. Calling flush after processing the queues results in two swaps which corrupts the next sample. Therefore it wasn't appropriate to call flush here so remove it.

In the cs_etm__sample(), if the period is not overflow, it is not necessarily to generate instruction samples and copy back stack entries. This is why we want to call cs_etm__flush() to make sure the last packet can be recorded properly for instruction sample with back stacks.

We also need to take account into the case for the end of the session - in this case we need to generate samples for the last packet for complete info.

I am wandering should we remove the cs_etm__packet_swap() from cs_etm__sample()?

Sorry for typo. I meant to remove the cs_etm__packet_swap() from cs_etm__flush().

Thanks, Leo

Turns out there was already cs_etm__end_block() for the end of the session, but it was only called for the timeless modes. I added it for timestamped mode too in V2.

I also kept the existing flush() function for discontinuities. I changed my mind that the differences to cs_etm__sample() weren't relevant.

So I think we still need to keep the swap in flush() because otherwise the next sample won't start from the right place.