Re: [PATCH] perf intel-pt: Fix ip compression

From: Adrian Hunter
Date: Wed Aug 10 2016 - 14:03:12 EST


On 20/07/16 12:00, Adrian Hunter wrote:
> June 2015 Intel SDM introduced IP Compression types 4 and 6. Refer section
> 36.4.2.2 Target IP (TIP) Packet - IP Compression.
>
> Existing Intel PT packet decoder did not support type 4, and got type 6
> wrong. Because type 3 and type 4 have the same number of bytes, the packet
> 'count' has been changed from being the number of ip bytes to being the
> type code. That allows the Intel PT decoder to correctly decide whether to
> sign-extend or use the last ip. However that also meant the code had to be
> adjusted in a number of places.
>
> Currently hardware is not using the new compression types, so this fix has
> no effect on existing hardware.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> ---
> .../perf/util/intel-pt-decoder/intel-pt-decoder.c | 44 +++++++++++-----------
> .../util/intel-pt-decoder/intel-pt-pkt-decoder.c | 24 ++++++++----
> 2 files changed, 40 insertions(+), 28 deletions(-)

Hi

This is outstanding but still applies.

Regards
Adrian