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[PATCH 01/37] perf intel-pt: Allow decoding with branch tracing disabled

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The kernel now supports the disabling of branch tracing, however the
decoder assumes branch tracing is always enabled. Pass through a parameter
to indicate whether branch tracing is enabled and use it to avoid cases
when the decoder is expecting branch packets. There are 2 such cases.
First, FUP packets which can bind to an IP even when there is no branch
tracing. Secondly, the decoder will try to use branch packets to find an IP
to start decoding or to recover from errors.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 13 +++++++++++++
 tools/perf/util/intel-pt-decoder/intel-pt-decoder.h |  1 +
 tools/perf/util/intel-pt.c                          | 14 ++++++++++++++
 3 files changed, 28 insertions(+)

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 7cf7f7aca4d2..9545b1a1872c 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -87,6 +87,7 @@ struct intel_pt_decoder {
 	const unsigned char *buf;
 	size_t len;
 	bool return_compression;
+	bool branch_enable;
 	bool mtc_insn;
 	bool pge;
 	bool have_tma;
@@ -192,6 +193,7 @@ struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
 	decoder->pgd_ip             = params->pgd_ip;
 	decoder->data               = params->data;
 	decoder->return_compression = params->return_compression;
+	decoder->branch_enable      = params->branch_enable;
 
 	decoder->period             = params->period;
 	decoder->period_type        = params->period_type;
@@ -1625,6 +1627,10 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
 				break;
 			}
 			intel_pt_set_last_ip(decoder);
+			if (!decoder->branch_enable) {
+				decoder->ip = decoder->last_ip;
+				break;
+			}
 			err = intel_pt_walk_fup(decoder);
 			if (err != -EAGAIN) {
 				if (err)
@@ -1935,6 +1941,13 @@ static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
 {
 	int err;
 
+	if (!decoder->branch_enable) {
+		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
+		decoder->overflow = false;
+		decoder->state.type = 0; /* Do not have a sample */
+		return 0;
+	}
+
 	intel_pt_log("Scanning for full IP\n");
 	err = intel_pt_walk_to_ip(decoder);
 	if (err)
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 e90619a43c0c..add3bed58349 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
@@ -87,6 +87,7 @@ struct intel_pt_params {
 	bool (*pgd_ip)(uint64_t ip, void *data);
 	void *data;
 	bool return_compression;
+	bool branch_enable;
 	uint64_t period;
 	enum intel_pt_period_type period_type;
 	unsigned max_non_turbo_ratio;
diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index 4c7718f87a08..5c59b8c6a719 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -668,6 +668,19 @@ static bool intel_pt_return_compression(struct intel_pt *pt)
 	return true;
 }
 
+static bool intel_pt_branch_enable(struct intel_pt *pt)
+{
+	struct perf_evsel *evsel;
+	u64 config;
+
+	evlist__for_each_entry(pt->session->evlist, evsel) {
+		if (intel_pt_get_config(pt, &evsel->attr, &config) &&
+		    (config & 1) && !(config & 0x2000))
+			return false;
+	}
+	return true;
+}
+
 static unsigned int intel_pt_mtc_period(struct intel_pt *pt)
 {
 	struct perf_evsel *evsel;
@@ -799,6 +812,7 @@ static struct intel_pt_queue *intel_pt_alloc_queue(struct intel_pt *pt,
 	params.walk_insn = intel_pt_walk_next_insn;
 	params.data = ptq;
 	params.return_compression = intel_pt_return_compression(pt);
+	params.branch_enable = intel_pt_branch_enable(pt);
 	params.max_non_turbo_ratio = pt->max_non_turbo_ratio;
 	params.mtc_period = intel_pt_mtc_period(pt);
 	params.tsc_ctc_ratio_n = pt->tsc_ctc_ratio_n;
-- 
1.9.1

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[PATCH 00/37] perf intel-pt: Power events and PTWRITE Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 30/37] perf intel-pt: Factor out intel_pt_set_event_name() Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 14/37] perf intel-pt: Add decoder support for CBR events Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 27/37] perf intel-pt: Join needlessly wrapped lines Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 17/37] perf tools: Fix message because cpu list option is -C not -c Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 07/37] perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 37/37] perf intel-pt: Improve sample timestamp Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
    Re: [PATCH 37/37] perf intel-pt: Improve sample timestamp Andi Kleen <ak@linux.intel.com> - 2017-05-19 16:40 +0200
  [PATCH 09/37] perf intel-pt: Add missing __fallthrough Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 19/37] perf script: Add 'synth' event type for synthesized events Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 35/37] perf intel-pt: Do not use TSC packets for calculating CPU cycles to TSC Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 05/37] perf intel-pt: Ensure IP is zero when state is INTEL_PT_STATE_NO_IP Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 03/37] perf intel-pt: Add documentation for new config terms Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 26/37] perf intel-pt: Remove unused instructions_sample_period Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 11/37] perf intel-pt: Add decoder support for ptwrite and power event packets Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 18/37] perf script: Fix message because field list option is -F not -f Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 13/37] perf intel-pt: Move decoder error setting into one condition Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 32/37] perf intel-pt: Synthesize new power and ptwrite events Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 15/37] perf intel-pt: Remove redundant initial_skip checks Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 24/37] perf script: Add synthesized Intel PT power and ptwrite events Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 36/37] perf auxtrace: Add CPU filter support Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 23/37] perf auxtrace: Add itrace option to output power events Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 25/37] perf intel-pt: Factor out common code synthesizing event samples Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 04/37] perf intel-pt: Fix missing stack clear Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 20/37] perf script: Add 'synth' field for synthesized event payloads Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 34/37] perf intel-pt: Update documentation to include new ptwrite and power events Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 10/37] perf intel-pt: Clear FUP flag on error Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 28/37] perf intel-pt: Tidy Intel PT evsel lookup into separate function Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 16/37] perf intel-pt: Fix transactions_sample_type Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:10 +0200
  [PATCH 01/37] perf intel-pt: Allow decoding with branch tracing disabled Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:20 +0200
  [PATCH 02/37] perf intel-pt: Add default config for pass-through branch enable Adrian Hunter <adrian.hunter@intel.com> - 2017-05-19 11:20 +0200

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