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Date: Fri, 10 Jul 2020 18:11:03 +0300
From: Adrian Hunter <adrian.hunter@...el.com>
To: Arnaldo Carvalho de Melo <acme@...nel.org>
Cc: Jiri Olsa <jolsa@...hat.com>, Andi Kleen <ak@...ux.intel.com>,
linux-kernel@...r.kernel.org
Subject: [PATCH V2 11/12] perf intel-pt: Add support for decoding FUP/TIP only
Use the new itrace 'q' option to add support for a mode of decoding that
ignores TNT, does not walk object code, but gets the ip from FUP and TIP
packets.
Example:
$ perf record -e intel_pt//u grep -rI pudding drivers
[ perf record: Woken up 52 times to write data ]
[ perf record: Captured and wrote 57.870 MB perf.data ]
$ time perf script --itrace=bi | wc -l
58948289
real 1m23.863s
user 1m23.251s
sys 0m7.452s
$ time perf script --itrace=biq | wc -l
3385694
real 0m4.453s
user 0m4.455s
sys 0m0.328s
Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
---
tools/perf/Documentation/perf-intel-pt.txt | 31 ++++
.../util/intel-pt-decoder/intel-pt-decoder.c | 167 +++++++++++++++++-
.../util/intel-pt-decoder/intel-pt-decoder.h | 1 +
tools/perf/util/intel-pt.c | 6 +-
4 files changed, 200 insertions(+), 5 deletions(-)
diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt
index 4666e4a83615..f9fe4a4040ba 100644
--- a/tools/perf/Documentation/perf-intel-pt.txt
+++ b/tools/perf/Documentation/perf-intel-pt.txt
@@ -825,6 +825,7 @@ The letters are:
l synthesize last branch entries (use with i or x)
L synthesize last branch entries on existing event records
s skip initial number of events
+ q quicker (less detailed) decoding
"Instructions" events look like they were recorded by "perf record -e
instructions".
@@ -969,6 +970,36 @@ at the beginning. This is useful to ignore initialization code.
skips the first million instructions.
+The q option changes the way the trace is decoded. The decoding is much faster
+but much less detailed. Specifically, with the q option, the decoder does not
+decode TNT packets, and does not walk object code, but gets the ip from FUP and
+TIP packets. The q option can be used with the b and i options but the period
+is not used. The q option decodes more quickly, but is useful only if the
+control flow of interest is represented or indicated by FUP, TIP, TIP.PGE, or
+TIP.PGD packets (refer below). However the q option could be used to find time
+ranges that could then be decoded fully using the --time option.
+
+What will *not* be decoded with the (single) q option:
+
+ - direct calls and jmps
+ - conditional branches
+ - non-branch instructions
+
+What *will* be decoded with the (single) q option:
+
+ - asynchronous branches such as interrupts
+ - indirect branches
+ - function return target address *if* the noretcomp config term (refer
+ config terms section) was used
+ - start of (control-flow) tracing
+ - end of (control-flow) tracing, if it is not out of context
+ - power events, ptwrite, transaction start and abort
+ - instruction pointer associated with PSB packets
+
+Note the q option does not specify what events will be synthesized e.g. the p
+option must be used also to show power events.
+
+
dump option
~~~~~~~~~~~
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 7ffcbd6fcd1a..ccb204b1a050 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -55,6 +55,7 @@ enum intel_pt_pkt_state {
INTEL_PT_STATE_TIP_PGD,
INTEL_PT_STATE_FUP,
INTEL_PT_STATE_FUP_NO_TIP,
+ INTEL_PT_STATE_RESAMPLE,
};
static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
@@ -65,6 +66,7 @@ static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
case INTEL_PT_STATE_ERR_RESYNC:
case INTEL_PT_STATE_IN_SYNC:
case INTEL_PT_STATE_TNT_CONT:
+ case INTEL_PT_STATE_RESAMPLE:
return true;
case INTEL_PT_STATE_TNT:
case INTEL_PT_STATE_TIP:
@@ -109,6 +111,8 @@ struct intel_pt_decoder {
bool fixup_last_mtc;
bool have_last_ip;
bool in_psb;
+ bool hop;
+ bool hop_psb_fup;
enum intel_pt_param_flags flags;
uint64_t pos;
uint64_t last_ip;
@@ -235,6 +239,7 @@ struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
decoder->data = params->data;
decoder->return_compression = params->return_compression;
decoder->branch_enable = params->branch_enable;
+ decoder->hop = params->quick >= 1;
decoder->flags = params->flags;
@@ -275,6 +280,9 @@ struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
+ if (decoder->hop)
+ intel_pt_log("Hop mode: decoding FUP and TIPs, but not TNT\n");
+
return decoder;
}
@@ -1730,8 +1738,14 @@ static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
case INTEL_PT_FUP:
decoder->pge = true;
- if (decoder->packet.count)
+ if (decoder->packet.count) {
intel_pt_set_last_ip(decoder);
+ if (decoder->hop) {
+ /* Act on FUP at PSBEND */
+ decoder->ip = decoder->last_ip;
+ decoder->hop_psb_fup = true;
+ }
+ }
break;
case INTEL_PT_MODE_TSX:
@@ -1875,6 +1889,118 @@ static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
}
}
+static int intel_pt_resample(struct intel_pt_decoder *decoder)
+{
+ decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
+ decoder->state.type = INTEL_PT_INSTRUCTION;
+ decoder->state.from_ip = decoder->ip;
+ decoder->state.to_ip = 0;
+ return 0;
+}
+
+#define HOP_PROCESS 0
+#define HOP_IGNORE 1
+#define HOP_RETURN 2
+#define HOP_AGAIN 3
+
+/* Hop mode: Ignore TNT, do not walk code, but get ip from FUPs and TIPs */
+static int intel_pt_hop_trace(struct intel_pt_decoder *decoder, bool *no_tip, int *err)
+{
+ switch (decoder->packet.type) {
+ case INTEL_PT_TNT:
+ return HOP_IGNORE;
+
+ case INTEL_PT_TIP_PGD:
+ if (!decoder->packet.count)
+ return HOP_IGNORE;
+ intel_pt_set_ip(decoder);
+ decoder->state.type |= INTEL_PT_TRACE_END;
+ decoder->state.from_ip = 0;
+ decoder->state.to_ip = decoder->ip;
+ return HOP_RETURN;
+
+ case INTEL_PT_TIP:
+ if (!decoder->packet.count)
+ return HOP_IGNORE;
+ intel_pt_set_ip(decoder);
+ decoder->state.type = INTEL_PT_INSTRUCTION;
+ decoder->state.from_ip = decoder->ip;
+ decoder->state.to_ip = 0;
+ return HOP_RETURN;
+
+ case INTEL_PT_FUP:
+ if (!decoder->packet.count)
+ return HOP_IGNORE;
+ intel_pt_set_ip(decoder);
+ if (intel_pt_fup_event(decoder))
+ return HOP_RETURN;
+ if (!decoder->branch_enable)
+ *no_tip = true;
+ if (*no_tip) {
+ decoder->state.type = INTEL_PT_INSTRUCTION;
+ decoder->state.from_ip = decoder->ip;
+ decoder->state.to_ip = 0;
+ return HOP_RETURN;
+ }
+ *err = intel_pt_walk_fup_tip(decoder);
+ if (!*err)
+ decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
+ return HOP_RETURN;
+
+ case INTEL_PT_PSB:
+ decoder->last_ip = 0;
+ decoder->have_last_ip = true;
+ decoder->hop_psb_fup = false;
+ *err = intel_pt_walk_psbend(decoder);
+ if (*err == -EAGAIN)
+ return HOP_AGAIN;
+ if (*err)
+ return HOP_RETURN;
+ if (decoder->hop_psb_fup) {
+ decoder->hop_psb_fup = false;
+ decoder->state.type = INTEL_PT_INSTRUCTION;
+ decoder->state.from_ip = decoder->ip;
+ decoder->state.to_ip = 0;
+ return HOP_RETURN;
+ }
+ if (decoder->cbr != decoder->cbr_seen) {
+ decoder->state.type = 0;
+ return HOP_RETURN;
+ }
+ return HOP_IGNORE;
+
+ case INTEL_PT_BAD:
+ case INTEL_PT_PAD:
+ case INTEL_PT_TIP_PGE:
+ case INTEL_PT_TSC:
+ case INTEL_PT_TMA:
+ case INTEL_PT_MODE_EXEC:
+ case INTEL_PT_MODE_TSX:
+ case INTEL_PT_MTC:
+ case INTEL_PT_CYC:
+ case INTEL_PT_VMCS:
+ case INTEL_PT_PSBEND:
+ case INTEL_PT_CBR:
+ case INTEL_PT_TRACESTOP:
+ case INTEL_PT_PIP:
+ case INTEL_PT_OVF:
+ case INTEL_PT_MNT:
+ case INTEL_PT_PTWRITE:
+ case INTEL_PT_PTWRITE_IP:
+ case INTEL_PT_EXSTOP:
+ case INTEL_PT_EXSTOP_IP:
+ case INTEL_PT_MWAIT:
+ case INTEL_PT_PWRE:
+ case INTEL_PT_PWRX:
+ case INTEL_PT_BBP:
+ case INTEL_PT_BIP:
+ case INTEL_PT_BEP:
+ case INTEL_PT_BEP_IP:
+ default:
+ return HOP_PROCESS;
+ }
+}
+
static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
{
bool no_tip = false;
@@ -1885,6 +2011,19 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
if (err)
return err;
next:
+ if (decoder->hop) {
+ switch (intel_pt_hop_trace(decoder, &no_tip, &err)) {
+ case HOP_IGNORE:
+ continue;
+ case HOP_RETURN:
+ return err;
+ case HOP_AGAIN:
+ goto next;
+ default:
+ break;
+ }
+ }
+
switch (decoder->packet.type) {
case INTEL_PT_TNT:
if (!decoder->packet.count)
@@ -1914,6 +2053,12 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
decoder->state.from_ip = 0;
decoder->state.to_ip = decoder->ip;
decoder->state.type |= INTEL_PT_TRACE_BEGIN;
+ /*
+ * In hop mode, resample to get the to_ip as an
+ * "instruction" sample.
+ */
+ if (decoder->hop)
+ decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
return 0;
}
@@ -2033,7 +2178,7 @@ static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
case INTEL_PT_MODE_TSX:
/* MODE_TSX need not be followed by FUP */
- if (!decoder->pge) {
+ if (!decoder->pge || decoder->in_psb) {
intel_pt_update_in_tx(decoder);
break;
}
@@ -2424,7 +2569,11 @@ static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
if (err)
return err;
- decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
+ /* In hop mode, resample to get the to_ip as an "instruction" sample */
+ if (decoder->hop)
+ decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
+ else
+ decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
decoder->overflow = false;
decoder->state.from_ip = 0;
@@ -2545,7 +2694,14 @@ static int intel_pt_sync(struct intel_pt_decoder *decoder)
if (decoder->ip) {
decoder->state.type = 0; /* Do not have a sample */
- decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
+ /*
+ * In hop mode, resample to get the PSB FUP ip as an
+ * "instruction" sample.
+ */
+ if (decoder->hop)
+ decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
+ else
+ decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
} else {
return intel_pt_sync_ip(decoder);
}
@@ -2609,6 +2765,9 @@ const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
if (err == -EAGAIN)
err = intel_pt_walk_trace(decoder);
break;
+ case INTEL_PT_STATE_RESAMPLE:
+ err = intel_pt_resample(decoder);
+ break;
default:
err = intel_pt_bug(decoder);
break;
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 e289e463d635..8645fc265481 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.h
@@ -250,6 +250,7 @@ struct intel_pt_params {
uint32_t tsc_ctc_ratio_n;
uint32_t tsc_ctc_ratio_d;
enum intel_pt_param_flags flags;
+ unsigned int quick;
};
struct intel_pt_decoder;
diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index bddeb18648df..7cb3cf769d4d 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -1030,6 +1030,7 @@ static struct intel_pt_queue *intel_pt_alloc_queue(struct intel_pt *pt,
params.mtc_period = intel_pt_mtc_period(pt);
params.tsc_ctc_ratio_n = pt->tsc_ctc_ratio_n;
params.tsc_ctc_ratio_d = pt->tsc_ctc_ratio_d;
+ params.quick = pt->synth_opts.quick;
if (pt->filts.cnt > 0)
params.pgd_ip = intel_pt_pgd_ip;
@@ -1423,7 +1424,10 @@ static int intel_pt_synth_instruction_sample(struct intel_pt_queue *ptq)
sample.id = ptq->pt->instructions_id;
sample.stream_id = ptq->pt->instructions_id;
- sample.period = ptq->state->tot_insn_cnt - ptq->last_insn_cnt;
+ if (pt->synth_opts.quick)
+ sample.period = 1;
+ else
+ sample.period = ptq->state->tot_insn_cnt - ptq->last_insn_cnt;
sample.cyc_cnt = ptq->ipc_cyc_cnt - ptq->last_in_cyc_cnt;
if (sample.cyc_cnt) {
--
2.17.1
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