The tail of a queue is supposed to be pointing to the next available
slot in a queue. In this implementation the tail is incremented before
it is used and as such points to the last used element, something that
has the immense advantage of centralizing tail management at a single
location and eliminating a lot of redundant code.
But this needs to be taken into consideration on the dequeueing side
where the head also needs to be incremented before it is used, or the
first available element of the queue will be skipped.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1527289854-10755-1-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
Added user space perf functionality to translate CoreSight traces into
instruction events with branch stack.
To invoke the new functionality, use the perf inject tool with
--itrace=il. For example, to translate the ETM trace from perf.data into
last branch records in a new inj.data file:
$ perf inject --itrace=i100000il128 -i perf.data -o perf.data.new
The 'i' parameter to itrace generates periodic instruction events. The
period between instruction events can be specified as a number of
instructions suffixed by i (default 100000).
The parameter to 'l' specifies the number of entries in the branch stack
attached to instruction events.
The 'b' parameter to itrace generates events on taken branches.
This patch also fixes the contents of the branch events used in perf
report - previously branch events were generated for each contiguous
range of instructions executed. These are fixed to generate branch
events between the last address of a range ending in an executed branch
instruction and the start address of the next range.
Based on patches by Sebastian Pop <s.pop@samsung.com> with additional fixes
and support for specifying the instruction period.
Originally-by: Sebastian Pop <s.pop@samsung.com>
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/1518607481-4059-2-git-send-email-robert.walker@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch adds functions to communicate with the openCSD trace decoder,
more specifically to access program memory, fetch trace packets and
reset the decoder.
Co-authored-by: Tor Jeremiassen <tor@ti.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1516211539-5166-7-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding functionality to create a CoreSight trace decoder capable
of decoding trace data pushed by a client application.
Co-authored-by: Tor Jeremiassen <tor@ti.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1516211539-5166-6-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch adds the required interface to the openCSD library to support
dumping CoreSight trace packet using the "report --dump" command. The
information conveyed is related to the type of packets gathered by a
trace session rather than full decoding.
Co-authored-by: Tor Jeremiassen <tor@ti.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1516211539-5166-5-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Mathieu Poirier