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perf intel-pt: Improve sample timestamp

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The decoder uses its current timestamp in samples. Usually that is a
timestamp that has already passed, but in some cases it is a timestamp
for a branch that the decoder is walking towards, and consequently
hasn't reached. Improve that situation by using the pkt_state to
determine when to use the current or previous timestamp.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Adrian Hunter 2017-05-26 11:17:03 +03:00 committed by Arnaldo Carvalho de Melo
parent 22c0689233
commit 3f04d98e97
1 changed files with 31 additions and 3 deletions
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34
tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
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@ -64,6 +64,25 @@ enum intel_pt_pkt_state {
INTEL_PT_STATE_FUP_NO_TIP,
};
static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
{
switch (pkt_state) {
case INTEL_PT_STATE_NO_PSB:
case INTEL_PT_STATE_NO_IP:
case INTEL_PT_STATE_ERR_RESYNC:
case INTEL_PT_STATE_IN_SYNC:
case INTEL_PT_STATE_TNT:
return true;
case INTEL_PT_STATE_TIP:
case INTEL_PT_STATE_TIP_PGD:
case INTEL_PT_STATE_FUP:
case INTEL_PT_STATE_FUP_NO_TIP:
return false;
default:
return true;
};
}
#ifdef INTEL_PT_STRICT
#define INTEL_PT_STATE_ERR1 INTEL_PT_STATE_NO_PSB
#define INTEL_PT_STATE_ERR2 INTEL_PT_STATE_NO_PSB
@ -99,6 +118,7 @@ struct intel_pt_decoder {
uint64_t timestamp;
uint64_t tsc_timestamp;
uint64_t ref_timestamp;
uint64_t sample_timestamp;
uint64_t ret_addr;
uint64_t ctc_timestamp;
uint64_t ctc_delta;
@ -139,6 +159,7 @@ struct intel_pt_decoder {
unsigned int fup_tx_flags;
unsigned int tx_flags;
uint64_t timestamp_insn_cnt;
uint64_t sample_insn_cnt;
uint64_t stuck_ip;
int no_progress;
int stuck_ip_prd;
@ -898,6 +919,7 @@ static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
decoder->tot_insn_cnt += insn_cnt;
decoder->timestamp_insn_cnt += insn_cnt;
decoder->sample_insn_cnt += insn_cnt;
decoder->period_insn_cnt += insn_cnt;
if (err) {
@ -2069,7 +2091,7 @@ static int intel_pt_sync(struct intel_pt_decoder *decoder)
static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
{
uint64_t est = decoder->timestamp_insn_cnt << 1;
uint64_t est = decoder->sample_insn_cnt << 1;
if (!decoder->cbr || !decoder->max_non_turbo_ratio)
goto out;
@ -2077,7 +2099,7 @@ static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
est *= decoder->max_non_turbo_ratio;
est /= decoder->cbr;
out:
return decoder->timestamp + est;
return decoder->sample_timestamp + est;
}
const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
@ -2133,11 +2155,17 @@ const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
if (err) {
decoder->state.err = intel_pt_ext_err(err);
decoder->state.from_ip = decoder->ip;
decoder->sample_timestamp = decoder->timestamp;
decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
} else {
decoder->state.err = 0;
if (intel_pt_sample_time(decoder->pkt_state)) {
decoder->sample_timestamp = decoder->timestamp;
decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
}
}
decoder->state.timestamp = decoder->timestamp;
decoder->state.timestamp = decoder->sample_timestamp;
decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
decoder->state.cr3 = decoder->cr3;
decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;