A single q option decodes ip from only FUP/TIP packets. Make it so that
repeating the q option (i.e. qq) decodes only PSB+, getting ip if there is
a FUP packet within PSB+ (i.e. between PSB and PSBEND).
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
$ time perf script --itrace=biqq | wc -l
1883
real 0m0.047s
user 0m0.043s
sys 0m0.009s
Signed-off-by: Adrian Hunter <[email protected]>
---
tools/perf/Documentation/perf-intel-pt.txt | 3 +++
.../util/intel-pt-decoder/intel-pt-decoder.c | 18 ++++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt
index 758295a7e3d6..849474629fe7 100644
--- a/tools/perf/Documentation/perf-intel-pt.txt
+++ b/tools/perf/Documentation/perf-intel-pt.txt
@@ -973,6 +973,9 @@ useful only if the control flow of interest is represented or indicated by FUP,
TIP, TIP.PGE, or TIP.PGD packets. However the q option could be used to find
time ranges that could then be decoded fully using the --time option.
+Repeating the q option (i.e. qq) decodes only PSB+, getting ip if there is a
+FUP packet within PSB+ (i.e. between PSB and PSBEND).
+
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 ccb204b1a050..697513f35154 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -113,6 +113,7 @@ struct intel_pt_decoder {
bool in_psb;
bool hop;
bool hop_psb_fup;
+ bool leap;
enum intel_pt_param_flags flags;
uint64_t pos;
uint64_t last_ip;
@@ -240,6 +241,7 @@ struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
decoder->return_compression = params->return_compression;
decoder->branch_enable = params->branch_enable;
decoder->hop = params->quick >= 1;
+ decoder->leap = params->quick >= 2;
decoder->flags = params->flags;
@@ -1903,9 +1905,18 @@ static int intel_pt_resample(struct intel_pt_decoder *decoder)
#define HOP_RETURN 2
#define HOP_AGAIN 3
+static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder);
+
/* 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)
{
+ /* Leap from PSB to PSB, getting ip from FUP within PSB+ */
+ if (decoder->leap && !decoder->in_psb && decoder->packet.type != INTEL_PT_PSB) {
+ *err = intel_pt_scan_for_psb(decoder);
+ if (*err)
+ return HOP_RETURN;
+ }
+
switch (decoder->packet.type) {
case INTEL_PT_TNT:
return HOP_IGNORE;
@@ -2681,6 +2692,7 @@ static int intel_pt_sync(struct intel_pt_decoder *decoder)
decoder->ip = 0;
intel_pt_clear_stack(&decoder->stack);
+leap:
err = intel_pt_scan_for_psb(decoder);
if (err)
return err;
@@ -2702,6 +2714,12 @@ static int intel_pt_sync(struct intel_pt_decoder *decoder)
decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
else
decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
+ } else if (decoder->leap) {
+ /*
+ * In leap mode, only PSB+ is decoded, so keeping leaping to the
+ * next PSB until there is an ip.
+ */
+ goto leap;
} else {
return intel_pt_sync_ip(decoder);
}
--
2.25.1
> diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt
> index 758295a7e3d6..849474629fe7 100644
> --- a/tools/perf/Documentation/perf-intel-pt.txt
> +++ b/tools/perf/Documentation/perf-intel-pt.txt
> @@ -973,6 +973,9 @@ useful only if the control flow of interest is represented or indicated by FUP,
> TIP, TIP.PGE, or TIP.PGD packets. However the q option could be used to find
> time ranges that could then be decoded fully using the --time option.
>
> +Repeating the q option (i.e. qq) decodes only PSB+, getting ip if there is a
> +FUP packet within PSB+ (i.e. between PSB and PSBEND).
Also need high level description without PT jargon
(and perhaps also reference how to configure PSB frequency)
Other than that great feature. I'll be an enthuisastic user :-)
-Andi
>