[PATCH v2 0/6] perf cs-etm: Support TRBE (unformatted decoding)

[PATCH v2 0/6] perf cs-etm: Support TRBE (unformatted decoding)

[James Clark]

This patchset consists of refactoring to allow the decoder to be
created in advance when the AUX records are iterated over. The
AUX record flags are used to communicate whether the data is
formatted or not which is the reason this refactoring is required.

These changes result in some simplifications, removal of early exit
conditions etc.

A change was also made to --dump-raw-trace code to allow the
formatted/unformatted status to persist and for the decoder to
not be continually deleted and recreated.

The changes apply on top of the previous patchset "[PATCH v7 0/2] perf
cs-etm: Split Coresight decode by aux records".

Changes since v1:
 * Change 'decoders_per_cpu' variable name to 'decoders' and add a comment
 * Add a warning that piped mode is best effort, suggested by Suzuki

James Clark (6):
  perf cs-etm: Refactor initialisation of kernel start address
  perf cs-etm: Split setup and timestamp search functions
  perf cs-etm: Only setup queues when they are modified
  perf cs-etm: Suppress printing when resetting decoder
  perf cs-etm: Use existing decoder instead of resetting it
  perf cs-etm: Pass unformatted flag to decoder

 .../perf/util/cs-etm-decoder/cs-etm-decoder.c |  14 +-
 tools/perf/util/cs-etm.c                      | 185 +++++++++---------
 2 files changed, 97 insertions(+), 102 deletions(-)

-- 
2.28.0

[PATCH v2 1/6] perf cs-etm: Refactor initialisation of kernel start address

[James Clark]

The kernel start address is already cached in the machine struct once it
is initialised, so storing it in the cs_etm struct is unnecessary.

It also depends on kernel maps being available to be initialised.
Therefore cs_etm__setup_queues() isn't an appropriate place to call it
because it could be called before processing starts. It would be better
to initialise it at the point when it is needed, then we can be sure
that all the necessary maps are available. Also by calling
machine__kernel_start() multiple times it can be initialised at some
point, even if it failed to initialise previously due to missing maps.

In a later commit cs_etm__setup_queues() will be moved which is the
motivation for this change.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
---
 tools/perf/util/cs-etm.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index bc1f64873c8f..4c69ef391f60 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -62,7 +62,6 @@ struct cs_etm_auxtrace {
 	u64 instructions_sample_period;
 	u64 instructions_id;
 	u64 **metadata;
-	u64 kernel_start;
 	unsigned int pmu_type;
 };
 
@@ -691,7 +690,7 @@ static u8 cs_etm__cpu_mode(struct cs_etm_queue *etmq, u64 address)
 
 	machine = etmq->etm->machine;
 
-	if (address >= etmq->etm->kernel_start) {
+	if (address >= machine__kernel_start(machine)) {
 		if (machine__is_host(machine))
 			return PERF_RECORD_MISC_KERNEL;
 		else
@@ -901,9 +900,6 @@ static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
 	unsigned int i;
 	int ret;
 
-	if (!etm->kernel_start)
-		etm->kernel_start = machine__kernel_start(etm->machine);
-
 	for (i = 0; i < etm->queues.nr_queues; i++) {
 		ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
 		if (ret)
-- 
2.28.0

[PATCH v2 2/6] perf cs-etm: Split setup and timestamp search functions

[James Clark]

This refactoring has some benefits:
 * Decoding is done to find the timestamp. If we want to print errors
   when maps aren't available, then doing it from cs_etm__setup_queue()
   may cause warnings to be printed.
 * The cs_etm__setup_queue() flow is shared between timed and timeless
   modes, so it needs to be guarded by an if statement which can now
   be removed.
 * Allows moving the setup queues function earlier.
 * If data was piped in, then not all queues would be filled so it
   wouldn't have worked properly anyway. Now it waits for flush so
   data in all queues will be available.

The motivation for this is to decouple setup functions with ones that
involve decoding. That way we can move the setup function earlier when
the formatted/unformatted trace information is available.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
---
 tools/perf/util/cs-etm.c | 41 ++++++++++++++++++++++++++++------------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 4c69ef391f60..426e99c07ca9 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -809,29 +809,32 @@ static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 			       struct auxtrace_queue *queue,
 			       unsigned int queue_nr)
 {
-	int ret = 0;
-	unsigned int cs_queue_nr;
-	u8 trace_chan_id;
-	u64 cs_timestamp;
 	struct cs_etm_queue *etmq = queue->priv;
 
 	if (list_empty(&queue->head) || etmq)
-		goto out;
+		return 0;
 
 	etmq = cs_etm__alloc_queue(etm);
 
-	if (!etmq) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!etmq)
+		return -ENOMEM;
 
 	queue->priv = etmq;
 	etmq->etm = etm;
 	etmq->queue_nr = queue_nr;
 	etmq->offset = 0;
 
-	if (etm->timeless_decoding)
-		goto out;
+	return 0;
+}
+
+static int cs_etm__queue_first_cs_timestamp(struct cs_etm_auxtrace *etm,
+					    struct cs_etm_queue *etmq,
+					    unsigned int queue_nr)
+{
+	int ret = 0;
+	unsigned int cs_queue_nr;
+	u8 trace_chan_id;
+	u64 cs_timestamp;
 
 	/*
 	 * We are under a CPU-wide trace scenario.  As such we need to know
@@ -2218,13 +2221,27 @@ static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
 static int cs_etm__process_queues(struct cs_etm_auxtrace *etm)
 {
 	int ret = 0;
-	unsigned int cs_queue_nr, queue_nr;
+	unsigned int cs_queue_nr, queue_nr, i;
 	u8 trace_chan_id;
 	u64 cs_timestamp;
 	struct auxtrace_queue *queue;
 	struct cs_etm_queue *etmq;
 	struct cs_etm_traceid_queue *tidq;
 
+	/*
+	 * Pre-populate the heap with one entry from each queue so that we can
+	 * start processing in time order across all queues.
+	 */
+	for (i = 0; i < etm->queues.nr_queues; i++) {
+		etmq = etm->queues.queue_array[i].priv;
+		if (!etmq)
+			continue;
+
+		ret = cs_etm__queue_first_cs_timestamp(etm, etmq, i);
+		if (ret)
+			return ret;
+	}
+
 	while (1) {
 		if (!etm->heap.heap_cnt)
 			goto out;
-- 
2.28.0

[PATCH v2 3/6] perf cs-etm: Only setup queues when they are modified

[James Clark]

Continually creating queues in cs_etm__process_event() is unnecessary.
They only need to be created when a buffer for a new CPU or thread is
encountered. This can be in two places, when building the queues in
advance in cs_etm__process_auxtrace_info(), or in
cs_etm__process_auxtrace_event() when data_queued is false and the
index wasn't available (pipe mode).

This change will allow the 'formatted' decoder setting to applied when
iterating over aux records in a later commit.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
---
 tools/perf/util/cs-etm.c | 54 +++++++++++-----------------------------
 1 file changed, 14 insertions(+), 40 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 426e99c07ca9..2d07e52ffd3c 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -96,7 +96,6 @@ struct cs_etm_queue {
 /* RB tree for quick conversion between traceID and metadata pointers */
 static struct intlist *traceid_list;
 
-static int cs_etm__update_queues(struct cs_etm_auxtrace *etm);
 static int cs_etm__process_queues(struct cs_etm_auxtrace *etm);
 static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
 					   pid_t tid);
@@ -564,7 +563,6 @@ static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
 static int cs_etm__flush_events(struct perf_session *session,
 				struct perf_tool *tool)
 {
-	int ret;
 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
 						   struct cs_etm_auxtrace,
 						   auxtrace);
@@ -574,11 +572,6 @@ static int cs_etm__flush_events(struct perf_session *session,
 	if (!tool->ordered_events)
 		return -EINVAL;
 
-	ret = cs_etm__update_queues(etm);
-
-	if (ret < 0)
-		return ret;
-
 	if (etm->timeless_decoding)
 		return cs_etm__process_timeless_queues(etm, -1);
 
@@ -898,30 +891,6 @@ static int cs_etm__queue_first_cs_timestamp(struct cs_etm_auxtrace *etm,
 	return ret;
 }
 
-static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
-{
-	unsigned int i;
-	int ret;
-
-	for (i = 0; i < etm->queues.nr_queues; i++) {
-		ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-
-static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
-{
-	if (etm->queues.new_data) {
-		etm->queues.new_data = false;
-		return cs_etm__setup_queues(etm);
-	}
-
-	return 0;
-}
-
 static inline
 void cs_etm__copy_last_branch_rb(struct cs_etm_queue *etmq,
 				 struct cs_etm_traceid_queue *tidq)
@@ -2395,7 +2364,6 @@ static int cs_etm__process_event(struct perf_session *session,
 				 struct perf_sample *sample,
 				 struct perf_tool *tool)
 {
-	int err = 0;
 	u64 sample_kernel_timestamp;
 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
 						   struct cs_etm_auxtrace,
@@ -2414,12 +2382,6 @@ static int cs_etm__process_event(struct perf_session *session,
 	else
 		sample_kernel_timestamp = 0;
 
-	if (sample_kernel_timestamp || etm->timeless_decoding) {
-		err = cs_etm__update_queues(etm);
-		if (err)
-			return err;
-	}
-
 	/*
 	 * Don't wait for cs_etm__flush_events() in per-thread/timeless mode to start the decode. We
 	 * need the tid of the PERF_RECORD_EXIT event to assign to the synthesised samples because
@@ -2476,6 +2438,7 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
 		int fd = perf_data__fd(session->data);
 		bool is_pipe = perf_data__is_pipe(session->data);
 		int err;
+		int idx = event->auxtrace.idx;
 
 		if (is_pipe)
 			data_offset = 0;
@@ -2490,6 +2453,11 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
 		if (err)
 			return err;
 
+		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
+					  idx);
+		if (err)
+			return err;
+
 		if (dump_trace)
 			if (auxtrace_buffer__get_data(buffer, fd)) {
 				cs_etm__dump_event(etm, buffer);
@@ -2732,6 +2700,7 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 	struct perf_record_auxtrace *auxtrace_event;
 	union perf_event auxtrace_fragment;
 	__u64 aux_offset, aux_size;
+	__u32 idx;
 
 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
 						   struct cs_etm_auxtrace,
@@ -2793,8 +2762,13 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 
 		pr_debug3("CS ETM: Queue buffer size: %#"PRI_lx64" offset: %#"PRI_lx64
 			  " tid: %d cpu: %d\n", aux_size, aux_offset, sample->tid, sample->cpu);
-		return auxtrace_queues__add_event(&etm->queues, session, &auxtrace_fragment,
-						  file_offset, NULL);
+		err = auxtrace_queues__add_event(&etm->queues, session, &auxtrace_fragment,
+						 file_offset, NULL);
+		if (err)
+			return err;
+
+		idx = auxtrace_event->idx;
+		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx], idx);
 	}
 
 	/* Wasn't inside this buffer, but there were no parse errors. 1 == 'not found' */
-- 
2.28.0

[PATCH v2 4/6] perf cs-etm: Suppress printing when resetting decoder

[James Clark]

The decoder is quite noisy when being reset. In a future commit,
dump-raw-trace will use a code path that resets the decoder rather than
creating a new one, so printing has to be suppressed to not flood the
output.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
---
 tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
index 3e1a05bc82cc..ed1f0326f859 100644
--- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
+++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
@@ -35,6 +35,7 @@
 struct cs_etm_decoder {
 	void *data;
 	void (*packet_printer)(const char *msg);
+	bool suppress_printing;
 	dcd_tree_handle_t dcd_tree;
 	cs_etm_mem_cb_type mem_access;
 	ocsd_datapath_resp_t prev_return;
@@ -74,9 +75,10 @@ int cs_etm_decoder__reset(struct cs_etm_decoder *decoder)
 	ocsd_datapath_resp_t dp_ret;
 
 	decoder->prev_return = OCSD_RESP_CONT;
-
+	decoder->suppress_printing = true;
 	dp_ret = ocsd_dt_process_data(decoder->dcd_tree, OCSD_OP_RESET,
 				      0, 0, NULL, NULL);
+	decoder->suppress_printing = false;
 	if (OCSD_DATA_RESP_IS_FATAL(dp_ret))
 		return -1;
 
@@ -146,8 +148,10 @@ static void cs_etm_decoder__print_str_cb(const void *p_context,
 					 const char *msg,
 					 const int str_len)
 {
-	if (p_context && str_len)
-		((struct cs_etm_decoder *)p_context)->packet_printer(msg);
+	const struct cs_etm_decoder *decoder = p_context;
+
+	if (p_context && str_len && !decoder->suppress_printing)
+		decoder->packet_printer(msg);
 }
 
 static int
-- 
2.28.0

[PATCH v2 5/6] perf cs-etm: Use existing decoder instead of resetting it

[James Clark]

When dumping trace, the decoder is continually deleted and recreated to
decode each buffer. To support both formatted and unformatted trace in
a later commit, the decoder will be configured in advance.

This commit removes the deletion of the decoder and allows the
formatted/unformatted setting to persist.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
---
 tools/perf/util/cs-etm.c | 37 +++++++------------------------------
 1 file changed, 7 insertions(+), 30 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 2d07e52ffd3c..760050ea936d 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -508,14 +508,11 @@ static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
 	return ret;
 }
 
-static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
+static void cs_etm__dump_event(struct cs_etm_queue *etmq,
 			       struct auxtrace_buffer *buffer)
 {
 	int ret;
 	const char *color = PERF_COLOR_BLUE;
-	struct cs_etm_decoder_params d_params;
-	struct cs_etm_trace_params *t_params;
-	struct cs_etm_decoder *decoder;
 	size_t buffer_used = 0;
 
 	fprintf(stdout, "\n");
@@ -523,29 +520,11 @@ static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
 		     ". ... CoreSight ETM Trace data: size %zu bytes\n",
 		     buffer->size);
 
-	/* Use metadata to fill in trace parameters for trace decoder */
-	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
-
-	if (!t_params)
-		return;
-
-	if (cs_etm__init_trace_params(t_params, etm))
-		goto out_free;
-
-	/* Set decoder parameters to simply print the trace packets */
-	if (cs_etm__init_decoder_params(&d_params, NULL,
-					CS_ETM_OPERATION_PRINT))
-		goto out_free;
-
-	decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
-
-	if (!decoder)
-		goto out_free;
 	do {
 		size_t consumed;
 
 		ret = cs_etm_decoder__process_data_block(
-				decoder, buffer->offset,
+				etmq->decoder, buffer->offset,
 				&((u8 *)buffer->data)[buffer_used],
 				buffer->size - buffer_used, &consumed);
 		if (ret)
@@ -554,10 +533,7 @@ static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
 		buffer_used += consumed;
 	} while (buffer_used < buffer->size);
 
-	cs_etm_decoder__free(decoder);
-
-out_free:
-	zfree(&t_params);
+	cs_etm_decoder__reset(etmq->decoder);
 }
 
 static int cs_etm__flush_events(struct perf_session *session,
@@ -769,7 +745,8 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
 
 	/* Set decoder parameters to decode trace packets */
 	if (cs_etm__init_decoder_params(&d_params, etmq,
-					CS_ETM_OPERATION_DECODE))
+					dump_trace ? CS_ETM_OPERATION_PRINT :
+						     CS_ETM_OPERATION_DECODE))
 		goto out_free;
 
 	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
@@ -2422,7 +2399,7 @@ static void dump_queued_data(struct cs_etm_auxtrace *etm,
 	for (i = 0; i < etm->queues.nr_queues; ++i)
 		list_for_each_entry(buf, &etm->queues.queue_array[i].head, list)
 			if (buf->reference == event->reference)
-				cs_etm__dump_event(etm, buf);
+				cs_etm__dump_event(etm->queues.queue_array[i].priv, buf);
 }
 
 static int cs_etm__process_auxtrace_event(struct perf_session *session,
@@ -2460,7 +2437,7 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
 
 		if (dump_trace)
 			if (auxtrace_buffer__get_data(buffer, fd)) {
-				cs_etm__dump_event(etm, buffer);
+				cs_etm__dump_event(etm->queues.queue_array[idx].priv, buffer);
 				auxtrace_buffer__put_data(buffer);
 			}
 	} else if (dump_trace)
-- 
2.28.0

[PATCH v2 6/6] perf cs-etm: Pass unformatted flag to decoder

[James Clark]

The TRBE (Trace Buffer Extension) feature allows a separate trace buffer
for each trace source, therefore the trace wouldn't need to be
formatted. The driver was introduced in commit 3fbf7f011f24
("coresight: sink: Add TRBE driver").

The formatted/unformatted mode is encoded in one of the flags of the
AUX record. The first AUX record encountered for each event is used to
determine the mode, and this will persist for the remaining trace that
is either decoded or dumped.

Signed-off-by: James Clark <james.clark@arm.com>
---
 .../perf/util/cs-etm-decoder/cs-etm-decoder.c |  4 +-
 tools/perf/util/cs-etm.c                      | 53 ++++++++++++++-----
 2 files changed, 42 insertions(+), 15 deletions(-)

diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
index ed1f0326f859..9c9039ae6989 100644
--- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
+++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
@@ -687,7 +687,7 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params,
 }
 
 struct cs_etm_decoder *
-cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
+cs_etm_decoder__new(int decoders, struct cs_etm_decoder_params *d_params,
 		    struct cs_etm_trace_params t_params[])
 {
 	struct cs_etm_decoder *decoder;
@@ -732,7 +732,7 @@ cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
 	/* init raw frame logging if required */
 	cs_etm_decoder__init_raw_frame_logging(d_params, decoder);
 
-	for (i = 0; i < num_cpu; i++) {
+	for (i = 0; i < decoders; i++) {
 		ret = cs_etm_decoder__create_etm_decoder(d_params,
 							 &t_params[i],
 							 decoder);
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 760050ea936d..f4b2bff533f3 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -461,13 +461,14 @@ static void cs_etm__set_trace_param_etmv4(struct cs_etm_trace_params *t_params,
 }
 
 static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
-				     struct cs_etm_auxtrace *etm)
+				     struct cs_etm_auxtrace *etm,
+				     int decoders)
 {
 	int i;
 	u32 etmidr;
 	u64 architecture;
 
-	for (i = 0; i < etm->num_cpu; i++) {
+	for (i = 0; i < decoders; i++) {
 		architecture = etm->metadata[i][CS_ETM_MAGIC];
 
 		switch (architecture) {
@@ -488,7 +489,8 @@ static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
 
 static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
 				       struct cs_etm_queue *etmq,
-				       enum cs_etm_decoder_operation mode)
+				       enum cs_etm_decoder_operation mode,
+				       bool formatted)
 {
 	int ret = -EINVAL;
 
@@ -498,7 +500,7 @@ static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
 	d_params->packet_printer = cs_etm__packet_dump;
 	d_params->operation = mode;
 	d_params->data = etmq;
-	d_params->formatted = true;
+	d_params->formatted = formatted;
 	d_params->fsyncs = false;
 	d_params->hsyncs = false;
 	d_params->frame_aligned = true;
@@ -720,11 +722,17 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
 	return len;
 }
 
-static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
+static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
+						bool formatted)
 {
 	struct cs_etm_decoder_params d_params;
 	struct cs_etm_trace_params  *t_params = NULL;
 	struct cs_etm_queue *etmq;
+	/*
+	 * Each queue can only contain data from one CPU when unformatted, so only one decoder is
+	 * needed.
+	 */
+	int decoders = formatted ? etm->num_cpu : 1;
 
 	etmq = zalloc(sizeof(*etmq));
 	if (!etmq)
@@ -735,21 +743,23 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
 		goto out_free;
 
 	/* Use metadata to fill in trace parameters for trace decoder */
-	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
+	t_params = zalloc(sizeof(*t_params) * decoders);
 
 	if (!t_params)
 		goto out_free;
 
-	if (cs_etm__init_trace_params(t_params, etm))
+	if (cs_etm__init_trace_params(t_params, etm, decoders))
 		goto out_free;
 
 	/* Set decoder parameters to decode trace packets */
 	if (cs_etm__init_decoder_params(&d_params, etmq,
 					dump_trace ? CS_ETM_OPERATION_PRINT :
-						     CS_ETM_OPERATION_DECODE))
+						     CS_ETM_OPERATION_DECODE,
+					formatted))
 		goto out_free;
 
-	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
+	etmq->decoder = cs_etm_decoder__new(decoders, &d_params,
+					    t_params);
 
 	if (!etmq->decoder)
 		goto out_free;
@@ -777,14 +787,15 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
 
 static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 			       struct auxtrace_queue *queue,
-			       unsigned int queue_nr)
+			       unsigned int queue_nr,
+			       bool formatted)
 {
 	struct cs_etm_queue *etmq = queue->priv;
 
 	if (list_empty(&queue->head) || etmq)
 		return 0;
 
-	etmq = cs_etm__alloc_queue(etm);
+	etmq = cs_etm__alloc_queue(etm, formatted);
 
 	if (!etmq)
 		return -ENOMEM;
@@ -2430,8 +2441,14 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
 		if (err)
 			return err;
 
+		/*
+		 * Knowing if the trace is formatted or not requires a lookup of
+		 * the aux record so only works in non-piped mode where data is
+		 * queued in cs_etm__queue_aux_records(). Always assume
+		 * formatted in piped mode (true).
+		 */
 		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
-					  idx);
+					  idx, true);
 		if (err)
 			return err;
 
@@ -2678,6 +2695,7 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 	union perf_event auxtrace_fragment;
 	__u64 aux_offset, aux_size;
 	__u32 idx;
+	bool formatted;
 
 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
 						   struct cs_etm_auxtrace,
@@ -2745,7 +2763,9 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 			return err;
 
 		idx = auxtrace_event->idx;
-		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx], idx);
+		formatted = !(aux_event->flags & PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
+		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
+					   idx, formatted);
 	}
 
 	/* Wasn't inside this buffer, but there were no parse errors. 1 == 'not found' */
@@ -3034,6 +3054,13 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
 		goto err_delete_thread;
 
 	etm->data_queued = etm->queues.populated;
+	/*
+	 * Print warning in pipe mode, see cs_etm__process_auxtrace_event() and
+	 * cs_etm__queue_aux_fragment() for details relating to limitations.
+	 */
+	if (!etm->data_queued)
+		pr_warning("CS ETM warning: Coresight decode and TRBE support requires random file access.\n"
+			   "Continuing with best effort decoding in piped mode.\n\n");
 
 	return 0;
 
-- 
2.28.0

Re: [PATCH v2 6/6] perf cs-etm: Pass unformatted flag to decoder

[Mathieu Poirier]

On Wed, Jul 21, 2021 at 04:02:02PM +0100, James Clark wrote:
> The TRBE (Trace Buffer Extension) feature allows a separate trace buffer
> for each trace source, therefore the trace wouldn't need to be
> formatted. The driver was introduced in commit 3fbf7f011f24
> ("coresight: sink: Add TRBE driver").
> 
> The formatted/unformatted mode is encoded in one of the flags of the
> AUX record. The first AUX record encountered for each event is used to
> determine the mode, and this will persist for the remaining trace that
> is either decoded or dumped.
> 
> Signed-off-by: James Clark <james.clark@arm.com>
> ---
>  .../perf/util/cs-etm-decoder/cs-etm-decoder.c |  4 +-
>  tools/perf/util/cs-etm.c                      | 53 ++++++++++++++-----
>  2 files changed, 42 insertions(+), 15 deletions(-)
> 

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>

Arnaldo, please consider adding this set to your tree.

Thanks,
Mathieu

> diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> index ed1f0326f859..9c9039ae6989 100644
> --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> @@ -687,7 +687,7 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params,
>  }
>  
>  struct cs_etm_decoder *
> -cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
> +cs_etm_decoder__new(int decoders, struct cs_etm_decoder_params *d_params,
>  		    struct cs_etm_trace_params t_params[])
>  {
>  	struct cs_etm_decoder *decoder;
> @@ -732,7 +732,7 @@ cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
>  	/* init raw frame logging if required */
>  	cs_etm_decoder__init_raw_frame_logging(d_params, decoder);
>  
> -	for (i = 0; i < num_cpu; i++) {
> +	for (i = 0; i < decoders; i++) {
>  		ret = cs_etm_decoder__create_etm_decoder(d_params,
>  							 &t_params[i],
>  							 decoder);
> diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> index 760050ea936d..f4b2bff533f3 100644
> --- a/tools/perf/util/cs-etm.c
> +++ b/tools/perf/util/cs-etm.c
> @@ -461,13 +461,14 @@ static void cs_etm__set_trace_param_etmv4(struct cs_etm_trace_params *t_params,
>  }
>  
>  static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
> -				     struct cs_etm_auxtrace *etm)
> +				     struct cs_etm_auxtrace *etm,
> +				     int decoders)
>  {
>  	int i;
>  	u32 etmidr;
>  	u64 architecture;
>  
> -	for (i = 0; i < etm->num_cpu; i++) {
> +	for (i = 0; i < decoders; i++) {
>  		architecture = etm->metadata[i][CS_ETM_MAGIC];
>  
>  		switch (architecture) {
> @@ -488,7 +489,8 @@ static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
>  
>  static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
>  				       struct cs_etm_queue *etmq,
> -				       enum cs_etm_decoder_operation mode)
> +				       enum cs_etm_decoder_operation mode,
> +				       bool formatted)
>  {
>  	int ret = -EINVAL;
>  
> @@ -498,7 +500,7 @@ static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
>  	d_params->packet_printer = cs_etm__packet_dump;
>  	d_params->operation = mode;
>  	d_params->data = etmq;
> -	d_params->formatted = true;
> +	d_params->formatted = formatted;
>  	d_params->fsyncs = false;
>  	d_params->hsyncs = false;
>  	d_params->frame_aligned = true;
> @@ -720,11 +722,17 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
>  	return len;
>  }
>  
> -static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
> +static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
> +						bool formatted)
>  {
>  	struct cs_etm_decoder_params d_params;
>  	struct cs_etm_trace_params  *t_params = NULL;
>  	struct cs_etm_queue *etmq;
> +	/*
> +	 * Each queue can only contain data from one CPU when unformatted, so only one decoder is
> +	 * needed.
> +	 */
> +	int decoders = formatted ? etm->num_cpu : 1;
>  
>  	etmq = zalloc(sizeof(*etmq));
>  	if (!etmq)
> @@ -735,21 +743,23 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
>  		goto out_free;
>  
>  	/* Use metadata to fill in trace parameters for trace decoder */
> -	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
> +	t_params = zalloc(sizeof(*t_params) * decoders);
>  
>  	if (!t_params)
>  		goto out_free;
>  
> -	if (cs_etm__init_trace_params(t_params, etm))
> +	if (cs_etm__init_trace_params(t_params, etm, decoders))
>  		goto out_free;
>  
>  	/* Set decoder parameters to decode trace packets */
>  	if (cs_etm__init_decoder_params(&d_params, etmq,
>  					dump_trace ? CS_ETM_OPERATION_PRINT :
> -						     CS_ETM_OPERATION_DECODE))
> +						     CS_ETM_OPERATION_DECODE,
> +					formatted))
>  		goto out_free;
>  
> -	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
> +	etmq->decoder = cs_etm_decoder__new(decoders, &d_params,
> +					    t_params);
>  
>  	if (!etmq->decoder)
>  		goto out_free;
> @@ -777,14 +787,15 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
>  
>  static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
>  			       struct auxtrace_queue *queue,
> -			       unsigned int queue_nr)
> +			       unsigned int queue_nr,
> +			       bool formatted)
>  {
>  	struct cs_etm_queue *etmq = queue->priv;
>  
>  	if (list_empty(&queue->head) || etmq)
>  		return 0;
>  
> -	etmq = cs_etm__alloc_queue(etm);
> +	etmq = cs_etm__alloc_queue(etm, formatted);
>  
>  	if (!etmq)
>  		return -ENOMEM;
> @@ -2430,8 +2441,14 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
>  		if (err)
>  			return err;
>  
> +		/*
> +		 * Knowing if the trace is formatted or not requires a lookup of
> +		 * the aux record so only works in non-piped mode where data is
> +		 * queued in cs_etm__queue_aux_records(). Always assume
> +		 * formatted in piped mode (true).
> +		 */
>  		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
> -					  idx);
> +					  idx, true);
>  		if (err)
>  			return err;
>  
> @@ -2678,6 +2695,7 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
>  	union perf_event auxtrace_fragment;
>  	__u64 aux_offset, aux_size;
>  	__u32 idx;
> +	bool formatted;
>  
>  	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
>  						   struct cs_etm_auxtrace,
> @@ -2745,7 +2763,9 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
>  			return err;
>  
>  		idx = auxtrace_event->idx;
> -		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx], idx);
> +		formatted = !(aux_event->flags & PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
> +		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
> +					   idx, formatted);
>  	}
>  
>  	/* Wasn't inside this buffer, but there were no parse errors. 1 == 'not found' */
> @@ -3034,6 +3054,13 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
>  		goto err_delete_thread;
>  
>  	etm->data_queued = etm->queues.populated;
> +	/*
> +	 * Print warning in pipe mode, see cs_etm__process_auxtrace_event() and
> +	 * cs_etm__queue_aux_fragment() for details relating to limitations.
> +	 */
> +	if (!etm->data_queued)
> +		pr_warning("CS ETM warning: Coresight decode and TRBE support requires random file access.\n"
> +			   "Continuing with best effort decoding in piped mode.\n\n");
>  
>  	return 0;
>  
> -- 
> 2.28.0
> 

Re: [PATCH v2 6/6] perf cs-etm: Pass unformatted flag to decoder

[Arnaldo Carvalho de Melo]

Em Wed, Jul 21, 2021 at 10:05:23AM -0600, Mathieu Poirier escreveu:
> On Wed, Jul 21, 2021 at 04:02:02PM +0100, James Clark wrote:
> > The TRBE (Trace Buffer Extension) feature allows a separate trace buffer
> > for each trace source, therefore the trace wouldn't need to be
> > formatted. The driver was introduced in commit 3fbf7f011f24
> > ("coresight: sink: Add TRBE driver").
> > 
> > The formatted/unformatted mode is encoded in one of the flags of the
> > AUX record. The first AUX record encountered for each event is used to
> > determine the mode, and this will persist for the remaining trace that
> > is either decoded or dumped.
> > 
> > Signed-off-by: James Clark <james.clark@arm.com>
> > ---
> >  .../perf/util/cs-etm-decoder/cs-etm-decoder.c |  4 +-
> >  tools/perf/util/cs-etm.c                      | 53 ++++++++++++++-----
> >  2 files changed, 42 insertions(+), 15 deletions(-)
> > 
> 
> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
> 
> Arnaldo, please consider adding this set to your tree.

Thanks, applied to perf/core.

- Arnaldo
 
> Thanks,
> Mathieu
> 
> > diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> > index ed1f0326f859..9c9039ae6989 100644
> > --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> > +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> > @@ -687,7 +687,7 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params,
> >  }
> >  
> >  struct cs_etm_decoder *
> > -cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
> > +cs_etm_decoder__new(int decoders, struct cs_etm_decoder_params *d_params,
> >  		    struct cs_etm_trace_params t_params[])
> >  {
> >  	struct cs_etm_decoder *decoder;
> > @@ -732,7 +732,7 @@ cs_etm_decoder__new(int num_cpu, struct cs_etm_decoder_params *d_params,
> >  	/* init raw frame logging if required */
> >  	cs_etm_decoder__init_raw_frame_logging(d_params, decoder);
> >  
> > -	for (i = 0; i < num_cpu; i++) {
> > +	for (i = 0; i < decoders; i++) {
> >  		ret = cs_etm_decoder__create_etm_decoder(d_params,
> >  							 &t_params[i],
> >  							 decoder);
> > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> > index 760050ea936d..f4b2bff533f3 100644
> > --- a/tools/perf/util/cs-etm.c
> > +++ b/tools/perf/util/cs-etm.c
> > @@ -461,13 +461,14 @@ static void cs_etm__set_trace_param_etmv4(struct cs_etm_trace_params *t_params,
> >  }
> >  
> >  static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
> > -				     struct cs_etm_auxtrace *etm)
> > +				     struct cs_etm_auxtrace *etm,
> > +				     int decoders)
> >  {
> >  	int i;
> >  	u32 etmidr;
> >  	u64 architecture;
> >  
> > -	for (i = 0; i < etm->num_cpu; i++) {
> > +	for (i = 0; i < decoders; i++) {
> >  		architecture = etm->metadata[i][CS_ETM_MAGIC];
> >  
> >  		switch (architecture) {
> > @@ -488,7 +489,8 @@ static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
> >  
> >  static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
> >  				       struct cs_etm_queue *etmq,
> > -				       enum cs_etm_decoder_operation mode)
> > +				       enum cs_etm_decoder_operation mode,
> > +				       bool formatted)
> >  {
> >  	int ret = -EINVAL;
> >  
> > @@ -498,7 +500,7 @@ static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
> >  	d_params->packet_printer = cs_etm__packet_dump;
> >  	d_params->operation = mode;
> >  	d_params->data = etmq;
> > -	d_params->formatted = true;
> > +	d_params->formatted = formatted;
> >  	d_params->fsyncs = false;
> >  	d_params->hsyncs = false;
> >  	d_params->frame_aligned = true;
> > @@ -720,11 +722,17 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
> >  	return len;
> >  }
> >  
> > -static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
> > +static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
> > +						bool formatted)
> >  {
> >  	struct cs_etm_decoder_params d_params;
> >  	struct cs_etm_trace_params  *t_params = NULL;
> >  	struct cs_etm_queue *etmq;
> > +	/*
> > +	 * Each queue can only contain data from one CPU when unformatted, so only one decoder is
> > +	 * needed.
> > +	 */
> > +	int decoders = formatted ? etm->num_cpu : 1;
> >  
> >  	etmq = zalloc(sizeof(*etmq));
> >  	if (!etmq)
> > @@ -735,21 +743,23 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
> >  		goto out_free;
> >  
> >  	/* Use metadata to fill in trace parameters for trace decoder */
> > -	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
> > +	t_params = zalloc(sizeof(*t_params) * decoders);
> >  
> >  	if (!t_params)
> >  		goto out_free;
> >  
> > -	if (cs_etm__init_trace_params(t_params, etm))
> > +	if (cs_etm__init_trace_params(t_params, etm, decoders))
> >  		goto out_free;
> >  
> >  	/* Set decoder parameters to decode trace packets */
> >  	if (cs_etm__init_decoder_params(&d_params, etmq,
> >  					dump_trace ? CS_ETM_OPERATION_PRINT :
> > -						     CS_ETM_OPERATION_DECODE))
> > +						     CS_ETM_OPERATION_DECODE,
> > +					formatted))
> >  		goto out_free;
> >  
> > -	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
> > +	etmq->decoder = cs_etm_decoder__new(decoders, &d_params,
> > +					    t_params);
> >  
> >  	if (!etmq->decoder)
> >  		goto out_free;
> > @@ -777,14 +787,15 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)
> >  
> >  static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
> >  			       struct auxtrace_queue *queue,
> > -			       unsigned int queue_nr)
> > +			       unsigned int queue_nr,
> > +			       bool formatted)
> >  {
> >  	struct cs_etm_queue *etmq = queue->priv;
> >  
> >  	if (list_empty(&queue->head) || etmq)
> >  		return 0;
> >  
> > -	etmq = cs_etm__alloc_queue(etm);
> > +	etmq = cs_etm__alloc_queue(etm, formatted);
> >  
> >  	if (!etmq)
> >  		return -ENOMEM;
> > @@ -2430,8 +2441,14 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
> >  		if (err)
> >  			return err;
> >  
> > +		/*
> > +		 * Knowing if the trace is formatted or not requires a lookup of
> > +		 * the aux record so only works in non-piped mode where data is
> > +		 * queued in cs_etm__queue_aux_records(). Always assume
> > +		 * formatted in piped mode (true).
> > +		 */
> >  		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
> > -					  idx);
> > +					  idx, true);
> >  		if (err)
> >  			return err;
> >  
> > @@ -2678,6 +2695,7 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
> >  	union perf_event auxtrace_fragment;
> >  	__u64 aux_offset, aux_size;
> >  	__u32 idx;
> > +	bool formatted;
> >  
> >  	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
> >  						   struct cs_etm_auxtrace,
> > @@ -2745,7 +2763,9 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
> >  			return err;
> >  
> >  		idx = auxtrace_event->idx;
> > -		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx], idx);
> > +		formatted = !(aux_event->flags & PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
> > +		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
> > +					   idx, formatted);
> >  	}
> >  
> >  	/* Wasn't inside this buffer, but there were no parse errors. 1 == 'not found' */
> > @@ -3034,6 +3054,13 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> >  		goto err_delete_thread;
> >  
> >  	etm->data_queued = etm->queues.populated;
> > +	/*
> > +	 * Print warning in pipe mode, see cs_etm__process_auxtrace_event() and
> > +	 * cs_etm__queue_aux_fragment() for details relating to limitations.
> > +	 */
> > +	if (!etm->data_queued)
> > +		pr_warning("CS ETM warning: Coresight decode and TRBE support requires random file access.\n"
> > +			   "Continuing with best effort decoding in piped mode.\n\n");
> >  
> >  	return 0;
> >  
> > -- 
> > 2.28.0
> > 

-- 

- Arnaldo