[tip:perf/core] perf tools: Fix Intel PT 'instructions' sample period

From: tip-bot for Adrian Hunter
Date: Fri Aug 28 2015 - 02:38:17 EST


Commit-ID: 2a21d03686881331b0af0471588674e7e896eeb2
Gitweb: http://git.kernel.org/tip/2a21d03686881331b0af0471588674e7e896eeb2
Author: Adrian Hunter <adrian.hunter@xxxxxxxxx>
AuthorDate: Fri, 17 Jul 2015 19:33:48 +0300
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 24 Aug 2015 17:42:26 -0300

perf tools: Fix Intel PT 'instructions' sample period

The period on synthesized 'instructions' samples was being set to a
fixed value, whereas the correct value is the number of instructions
since the last sample, which is a value that the decoder can provide.
So do it that way.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1437150840-31811-14-git-send-email-adrian.hunter@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 3 +++
tools/perf/util/intel-pt-decoder/intel-pt-decoder.h | 1 +
tools/perf/util/intel-pt.c | 5 ++++-
3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
index f8ac462..56790ea 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -108,6 +108,7 @@ struct intel_pt_decoder {
uint64_t sign_bits;
uint64_t period;
enum intel_pt_period_type period_type;
+ uint64_t tot_insn_cnt;
uint64_t period_insn_cnt;
uint64_t period_mask;
uint64_t period_ticks;
@@ -559,6 +560,7 @@ static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
max_insn_cnt, decoder->data);

+ decoder->tot_insn_cnt += insn_cnt;
decoder->timestamp_insn_cnt += insn_cnt;
decoder->period_insn_cnt += insn_cnt;

@@ -1529,6 +1531,7 @@ const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
decoder->state.timestamp = decoder->timestamp;
decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
decoder->state.cr3 = decoder->cr3;
+ decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;

if (err)
decoder->state.from_ip = decoder->ip;
diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
index 4c48802..cbf5704 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
@@ -58,6 +58,7 @@ struct intel_pt_state {
uint64_t from_ip;
uint64_t to_ip;
uint64_t cr3;
+ uint64_t tot_insn_cnt;
uint64_t timestamp;
uint64_t est_timestamp;
uint64_t trace_nr;
diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index a5acd2f..3b34a64 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -126,6 +126,7 @@ struct intel_pt_queue {
u64 timestamp;
u32 flags;
u16 insn_len;
+ u64 last_insn_cnt;
};

static void intel_pt_dump(struct intel_pt *pt __maybe_unused,
@@ -920,11 +921,13 @@ static int intel_pt_synth_instruction_sample(struct intel_pt_queue *ptq)
sample.addr = ptq->state->to_ip;
sample.id = ptq->pt->instructions_id;
sample.stream_id = ptq->pt->instructions_id;
- sample.period = ptq->pt->instructions_sample_period;
+ sample.period = ptq->state->tot_insn_cnt - ptq->last_insn_cnt;
sample.cpu = ptq->cpu;
sample.flags = ptq->flags;
sample.insn_len = ptq->insn_len;

+ ptq->last_insn_cnt = ptq->state->tot_insn_cnt;
+
if (pt->synth_opts.callchain) {
thread_stack__sample(ptq->thread, ptq->chain,
pt->synth_opts.callchain_sz, sample.ip);
--
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