perf intel-pt: Fix TSC slip
authorAdrian Hunter <adrian.hunter@intel.com>
Mon, 25 Mar 2019 13:51:35 +0000 (15:51 +0200)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Thu, 28 Mar 2019 17:31:55 +0000 (14:31 -0300)
commitf3b4e06b3bda759afd042d3d5fa86bea8f1fe278
tree795a322f98bd67431e16e096282784f56e3d26fe
parentc8fa7a807f3c5f946bd92076fbaf7826edb650dc
perf intel-pt: Fix TSC slip

A TSC packet can slip past MTC packets so that the timestamp appears to
go backwards. One estimate is that can be up to about 40 CPU cycles,
which is certainly less than 0x1000 TSC ticks, but accept slippage an
order of magnitude more to be on the safe side.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 79b58424b821c ("perf tools: Add Intel PT support for decoding MTC packets")
Link: http://lkml.kernel.org/r/20190325135135.18348-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/intel-pt-decoder/intel-pt-decoder.c