There may be discontinuities in the ETM trace stream due to overflows or ETM configuration for selective trace. This patch emits an instruction sample with the pending branch stack when a TRACE ON packet occurs indicating a discontinuity in the trace data. A new packet type CS_ETM_TRACE_ON is added, which is emitted by the low level decoder when a TRACE ON occurs. The higher level decoder flushes the branch stack when this packet is emitted. Signed-off-by: Robert Walker <robert.walker@arm.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1518607481-4059-3-git-send-email-robert.walker@arm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>