Commit a4973d8f authored Aug 15, 2019 by Leo Yan Committed by Arnaldo Carvalho de Melo Aug 20, 2019

perf cs-etm: Support sample flags 'insn' and 'insnlen'



The synthetic branch and instruction samples are missed to set
instruction related info, thus the perf tool fails to display samples
with flags '-F,+insn,+insnlen'.

The CoreSight trace decoder provides sufficient information to decide
the instruction size based on the ISA type: A64/A32 instructions are
32-bit size, but one exception is the T32 instruction size, which might
be 32-bit or 16-bit.

This patch handles these cases and it reads the instruction values from
DSO file; thus can support the flags '-F,+insn,+insnlen'.

Before:

  # perf script -F,insn,insnlen,ip,sym
                0 [unknown] ilen: 0
     ffff97174044 _start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0
     ffff97174938 _dl_start ilen: 0

  [...]

After:

  # perf script -F,insn,insnlen,ip,sym
                0 [unknown] ilen: 0
     ffff97174044 _start ilen: 4 insn: 2f 02 00 94
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54
     ffff97174938 _dl_start ilen: 4 insn: c1 ff ff 54

  [...]

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190815082854.18191-1-leo.yan@linaro.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 10ccbc1c

tools/perf/util/cs-etm.c

+34 −1

Original line number	Diff line number	Diff line
		@@ -1076,6 +1076,35 @@ bool cs_etm__etmq_is_timeless(struct cs_etm_queue *etmq)
		return !!etmq->etm->timeless_decoding;
		}

		static void cs_etm__copy_insn(struct cs_etm_queue *etmq,
		u64 trace_chan_id,
		const struct cs_etm_packet *packet,
		struct perf_sample *sample)
		{
		/*
		* It's pointless to read instructions for the CS_ETM_DISCONTINUITY
		* packet, so directly bail out with 'insn_len' = 0.
		*/
		if (packet->sample_type == CS_ETM_DISCONTINUITY) {
		sample->insn_len = 0;
		return;
		}

		/*
		* T32 instruction size might be 32-bit or 16-bit, decide by calling
		* cs_etm__t32_instr_size().
		*/
		if (packet->isa == CS_ETM_ISA_T32)
		sample->insn_len = cs_etm__t32_instr_size(etmq, trace_chan_id,
		sample->ip);
		/* Otherwise, A64 and A32 instruction size are always 32-bit. */
		else
		sample->insn_len = 4;

		cs_etm__mem_access(etmq, trace_chan_id, sample->ip,
		sample->insn_len, (void *)sample->insn);
		}

		static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
		struct cs_etm_traceid_queue *tidq,
		u64 addr, u64 period)
		@@ -1097,9 +1126,10 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
		sample.period = period;
		sample.cpu = tidq->packet->cpu;
		sample.flags = tidq->prev_packet->flags;
		sample.insn_len = 1;
		sample.cpumode = event->sample.header.misc;

		cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->packet, &sample);

		if (etm->synth_opts.last_branch) {
		cs_etm__copy_last_branch_rb(etmq, tidq);
		sample.branch_stack = tidq->last_branch;
		@@ -1159,6 +1189,9 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq,
		sample.flags = tidq->prev_packet->flags;
		sample.cpumode = event->sample.header.misc;

		cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->prev_packet,
		&sample);

		/*
		* perf report cannot handle events without a branch stack
		*/

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