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| Started by | Adrian Hunter <adrian.hunter@intel.com> |
|---|---|
| First post | 2016-09-28 13:50 +0200 |
| Last post | 2016-10-07 00:50 +0200 |
| Articles | 6 — 3 participants |
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[PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode Adrian Hunter <adrian.hunter@intel.com> - 2016-09-28 13:50 +0200
[PATCH 2/2] perf intel-pt: Fix MTC timestamp calculation for large MTC periods Adrian Hunter <adrian.hunter@intel.com> - 2016-09-28 13:50 +0200
[tip:perf/urgent] perf intel-pt: Fix MTC timestamp calculation for large MTC periods tip-bot for Adrian Hunter <tipbot@zytor.com> - 2016-10-07 00:50 +0200
Re: [PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode Adrian Hunter <adrian.hunter@intel.com> - 2016-10-05 09:40 +0200
Re: [PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode Arnaldo Carvalho de Melo <acme@kernel.org> - 2016-10-05 13:20 +0200
[tip:perf/urgent] perf intel-pt: Fix estimated timestamps for cycle-accurate mode tip-bot for Adrian Hunter <tipbot@zytor.com> - 2016-10-07 00:50 +0200
| From | Adrian Hunter <adrian.hunter@intel.com> |
|---|---|
| Date | 2016-09-28 13:50 +0200 |
| Subject | [PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode |
| Message-ID | <smlx7-66C-1@gated-at.bofh.it> |
In cycle-accurate mode, timestamps can be calculated from CYC packets. The decoder also estimates timestamps based on the number of instructions since the last timestamp. For that to work in cycle-accurate mode, the instruction count needs to be reset to zero when a timestamp is calculated from a CYC packet, but that wasn't happening, so fix it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org # v4.3+ --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++ 1 file changed, 2 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 7591a0c37473..3d1d446f037f 100644 --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1353,6 +1353,8 @@ static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder) timestamp, decoder->timestamp); else decoder->timestamp = timestamp; + + decoder->timestamp_insn_cnt = 0; } /* Walk PSB+ packets when already in sync. */ -- 1.9.1
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| From | Adrian Hunter <adrian.hunter@intel.com> |
|---|---|
| Date | 2016-09-28 13:50 +0200 |
| Subject | [PATCH 2/2] perf intel-pt: Fix MTC timestamp calculation for large MTC periods |
| Message-ID | <smlx8-66C-5@gated-at.bofh.it> |
| In reply to | #1492540 |
The MTC packet provides a 8-bit slice of CTC which is related to TSC by the
TMA packet, however the TMA packet only provides the lower 16 bits of CTC.
If mtc_shift > 8 then some of the MTC bits are not in the CTC provided by
the TMA packet. Fix-up the last_mtc calculated from the TMA packet by
copying the missing bits from the current MTC assuming the least difference
between the two, and that the current MTC comes after last_mtc.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v4.3+
---
.../perf/util/intel-pt-decoder/intel-pt-decoder.c | 36 ++++++++++++++++++++++
1 file changed, 36 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 3d1d446f037f..16c06d3ae577 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -90,6 +90,7 @@ struct intel_pt_decoder {
bool pge;
bool have_tma;
bool have_cyc;
+ bool fixup_last_mtc;
uint64_t pos;
uint64_t last_ip;
uint64_t ip;
@@ -586,10 +587,31 @@ struct intel_pt_calc_cyc_to_tsc_info {
uint64_t tsc_timestamp;
uint64_t timestamp;
bool have_tma;
+ bool fixup_last_mtc;
bool from_mtc;
double cbr_cyc_to_tsc;
};
+/*
+ * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
+ * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
+ * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
+ * packet by copying the missing bits from the current MTC assuming the least
+ * difference between the two, and that the current MTC comes after last_mtc.
+ */
+static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
+ uint32_t *last_mtc)
+{
+ uint32_t first_missing_bit = 1U << (16 - mtc_shift);
+ uint32_t mask = ~(first_missing_bit - 1);
+
+ *last_mtc |= mtc & mask;
+ if (*last_mtc >= mtc) {
+ *last_mtc -= first_missing_bit;
+ *last_mtc &= 0xff;
+ }
+}
+
static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
{
struct intel_pt_decoder *decoder = pkt_info->decoder;
@@ -619,6 +641,11 @@ static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
return 0;
mtc = pkt_info->packet.payload;
+ if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
+ data->fixup_last_mtc = false;
+ intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
+ &data->last_mtc);
+ }
if (mtc > data->last_mtc)
mtc_delta = mtc - data->last_mtc;
else
@@ -687,6 +714,7 @@ static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
data->ctc_delta = 0;
data->have_tma = true;
+ data->fixup_last_mtc = true;
return 0;
@@ -753,6 +781,7 @@ static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
.tsc_timestamp = decoder->tsc_timestamp,
.timestamp = decoder->timestamp,
.have_tma = decoder->have_tma,
+ .fixup_last_mtc = decoder->fixup_last_mtc,
.from_mtc = from_mtc,
.cbr_cyc_to_tsc = 0,
};
@@ -1271,6 +1300,7 @@ static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
}
decoder->ctc_delta = 0;
decoder->have_tma = true;
+ decoder->fixup_last_mtc = true;
intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x CTC rem %#x\n",
decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
}
@@ -1285,6 +1315,12 @@ static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
mtc = decoder->packet.payload;
+ if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
+ decoder->fixup_last_mtc = false;
+ intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
+ &decoder->last_mtc);
+ }
+
if (mtc > decoder->last_mtc)
mtc_delta = mtc - decoder->last_mtc;
else
--
1.9.1
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| From | tip-bot for Adrian Hunter <tipbot@zytor.com> |
|---|---|
| Date | 2016-10-07 00:50 +0200 |
| Subject | [tip:perf/urgent] perf intel-pt: Fix MTC timestamp calculation for large MTC periods |
| Message-ID | <sppEd-7qB-25@gated-at.bofh.it> |
| In reply to | #1492542 |
Commit-ID: 3bccbe20f6d188ce7b00326e776b745cfd35b10a
Gitweb: http://git.kernel.org/tip/3bccbe20f6d188ce7b00326e776b745cfd35b10a
Author: Adrian Hunter <adrian.hunter@intel.com>
AuthorDate: Wed, 28 Sep 2016 14:41:36 +0300
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 5 Oct 2016 08:15:58 -0300
perf intel-pt: Fix MTC timestamp calculation for large MTC periods
The MTC packet provides a 8-bit slice of CTC which is related to TSC by
the TMA packet, however the TMA packet only provides the lower 16 bits
of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
packet by copying the missing bits from the current MTC assuming the
least difference between the two, and that the current MTC comes after
last_mtc.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.3+
Link: http://lkml.kernel.org/r/1475062896-22274-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
.../perf/util/intel-pt-decoder/intel-pt-decoder.c | 36 ++++++++++++++++++++++
1 file changed, 36 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 3d1d446..16c06d3 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -90,6 +90,7 @@ struct intel_pt_decoder {
bool pge;
bool have_tma;
bool have_cyc;
+ bool fixup_last_mtc;
uint64_t pos;
uint64_t last_ip;
uint64_t ip;
@@ -586,10 +587,31 @@ struct intel_pt_calc_cyc_to_tsc_info {
uint64_t tsc_timestamp;
uint64_t timestamp;
bool have_tma;
+ bool fixup_last_mtc;
bool from_mtc;
double cbr_cyc_to_tsc;
};
+/*
+ * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
+ * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
+ * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
+ * packet by copying the missing bits from the current MTC assuming the least
+ * difference between the two, and that the current MTC comes after last_mtc.
+ */
+static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
+ uint32_t *last_mtc)
+{
+ uint32_t first_missing_bit = 1U << (16 - mtc_shift);
+ uint32_t mask = ~(first_missing_bit - 1);
+
+ *last_mtc |= mtc & mask;
+ if (*last_mtc >= mtc) {
+ *last_mtc -= first_missing_bit;
+ *last_mtc &= 0xff;
+ }
+}
+
static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
{
struct intel_pt_decoder *decoder = pkt_info->decoder;
@@ -619,6 +641,11 @@ static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
return 0;
mtc = pkt_info->packet.payload;
+ if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
+ data->fixup_last_mtc = false;
+ intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
+ &data->last_mtc);
+ }
if (mtc > data->last_mtc)
mtc_delta = mtc - data->last_mtc;
else
@@ -687,6 +714,7 @@ static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
data->ctc_delta = 0;
data->have_tma = true;
+ data->fixup_last_mtc = true;
return 0;
@@ -753,6 +781,7 @@ static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
.tsc_timestamp = decoder->tsc_timestamp,
.timestamp = decoder->timestamp,
.have_tma = decoder->have_tma,
+ .fixup_last_mtc = decoder->fixup_last_mtc,
.from_mtc = from_mtc,
.cbr_cyc_to_tsc = 0,
};
@@ -1271,6 +1300,7 @@ static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
}
decoder->ctc_delta = 0;
decoder->have_tma = true;
+ decoder->fixup_last_mtc = true;
intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x CTC rem %#x\n",
decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
}
@@ -1285,6 +1315,12 @@ static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
mtc = decoder->packet.payload;
+ if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
+ decoder->fixup_last_mtc = false;
+ intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
+ &decoder->last_mtc);
+ }
+
if (mtc > decoder->last_mtc)
mtc_delta = mtc - decoder->last_mtc;
else
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| From | Adrian Hunter <adrian.hunter@intel.com> |
|---|---|
| Date | 2016-10-05 09:40 +0200 |
| Subject | Re: [PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode |
| Message-ID | <soOY1-67p-15@gated-at.bofh.it> |
| In reply to | #1492540 |
On 28/09/16 14:41, Adrian Hunter wrote: > In cycle-accurate mode, timestamps can be calculated from CYC packets. The > decoder also estimates timestamps based on the number of instructions since > the last timestamp. For that to work in cycle-accurate mode, the > instruction count needs to be reset to zero when a timestamp is calculated > from a CYC packet, but that wasn't happening, so fix it. > > Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> > Cc: stable@vger.kernel.org # v4.3+ Hi These 2 patches are still outstanding when you have time. Regards Adrian > --- > tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++ > 1 file changed, 2 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 7591a0c37473..3d1d446f037f 100644 > --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c > +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c > @@ -1353,6 +1353,8 @@ static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder) > timestamp, decoder->timestamp); > else > decoder->timestamp = timestamp; > + > + decoder->timestamp_insn_cnt = 0; > } > > /* Walk PSB+ packets when already in sync. */ >
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| From | Arnaldo Carvalho de Melo <acme@kernel.org> |
|---|---|
| Date | 2016-10-05 13:20 +0200 |
| Subject | Re: [PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode |
| Message-ID | <soSoV-ft-5@gated-at.bofh.it> |
| In reply to | #1495730 |
Em Wed, Oct 05, 2016 at 10:33:14AM +0300, Adrian Hunter escreveu: > On 28/09/16 14:41, Adrian Hunter wrote: > > In cycle-accurate mode, timestamps can be calculated from CYC packets. The > > decoder also estimates timestamps based on the number of instructions since > > the last timestamp. For that to work in cycle-accurate mode, the > > instruction count needs to be reset to zero when a timestamp is calculated > > from a CYC packet, but that wasn't happening, so fix it. > > > > Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> > > Cc: stable@vger.kernel.org # v4.3+ > > Hi > > These 2 patches are still outstanding when you have time. Thanks for the reminder, applied. > Regards > Adrian > > > --- > > tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++ > > 1 file changed, 2 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 7591a0c37473..3d1d446f037f 100644 > > --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c > > +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c > > @@ -1353,6 +1353,8 @@ static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder) > > timestamp, decoder->timestamp); > > else > > decoder->timestamp = timestamp; > > + > > + decoder->timestamp_insn_cnt = 0; > > } > > > > /* Walk PSB+ packets when already in sync. */ > >
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| From | tip-bot for Adrian Hunter <tipbot@zytor.com> |
|---|---|
| Date | 2016-10-07 00:50 +0200 |
| Subject | [tip:perf/urgent] perf intel-pt: Fix estimated timestamps for cycle-accurate mode |
| Message-ID | <sppEe-7qB-35@gated-at.bofh.it> |
| In reply to | #1492540 |
Commit-ID: 51ee6481fa8e879cc942bcc1b0af713e158b7a98 Gitweb: http://git.kernel.org/tip/51ee6481fa8e879cc942bcc1b0af713e158b7a98 Author: Adrian Hunter <adrian.hunter@intel.com> AuthorDate: Wed, 28 Sep 2016 14:41:35 +0300 Committer: Arnaldo Carvalho de Melo <acme@redhat.com> CommitDate: Wed, 5 Oct 2016 08:15:29 -0300 perf intel-pt: Fix estimated timestamps for cycle-accurate mode In cycle-accurate mode, timestamps can be calculated from CYC packets. The decoder also estimates timestamps based on the number of instructions since the last timestamp. For that to work in cycle-accurate mode, the instruction count needs to be reset to zero when a timestamp is calculated from a CYC packet, but that wasn't happening, so fix it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: stable@vger.kernel.org # v4.3+ Link: http://lkml.kernel.org/r/1475062896-22274-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++ 1 file changed, 2 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 7591a0c..3d1d446 100644 --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1353,6 +1353,8 @@ static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder) timestamp, decoder->timestamp); else decoder->timestamp = timestamp; + + decoder->timestamp_insn_cnt = 0; } /* Walk PSB+ packets when already in sync. */
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