[PATCH] perf arm-spe: Fix incorrect sample timestamp in perf script
From: Yang Jihong <hidden>
Date: 2021-06-26 03:20:34
Also in:
linux-perf-users, lkml
Subsystem:
performance events subsystem, performance events tooling arm64, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
When use perf script to parse ARM SPE data, sample timestamp does not match
the timestamp stored in the AUX buffer, arm_spe_prep_sample function set
"samlpe->time = speq->timestamp", "speq->timestamp" is the timestamp of first
packet in auxtrace buffer. As a result, the time of all samples in a auxtrace
buffer uses the same timestamp.
Before:
# perf record -e arm_spe_0/ts_enable=1,branch_filter=1/ ls
perf.data
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.029 MB perf.data ]
[ perf record: Captured and wrote 1.429 MB perf.data ]
# perf script -D
[...]
0 0 0x31b0 [0x30]: PERF_RECORD_AUXTRACE size: 0x44f0 offset: 0 ref: 0x3a50d idx: 5 tid: 107690 cpu: 5
.
[...]
. 00000108: b0 00 82 f3 29 ee b7 ff c0 PC 0xffb7ee29f38200 el2 ns=1
. 00000111: 99 02 00 LAT 2 ISSUE
. 00000114: 98 03 00 LAT 3 TOT
. 00000117: 52 82 00 EV RETIRED MISPRED
. 0000011a: 4a 01 B COND
. 0000011c: b1 24 82 f3 29 ee b7 ff c0 TGT 0xffb7ee29f38224 el2 ns=1
. 00000125: 00 00 00 00 00 00 PAD
. 0000012b: 71 32 a0 d6 78 3f 07 00 00 TS 7969191665714
[...]
. 0000018c: b0 0c e1 20 2a ee b7 ff c0 PC 0xffb7ee2a20e10c el2 ns=1
. 00000195: 99 02 00 LAT 2 ISSUE
. 00000198: 98 03 00 LAT 3 TOT
. 0000019b: 52 c2 00 EV RETIRED NOT-TAKEN MISPRED
. 0000019e: 4a 01 B COND
. 000001a0: b1 10 e1 20 2a ee b7 ff c0 TGT 0xffb7ee2a20e110 el2 ns=1
. 000001a9: 00 00 00 00 00 00 PAD
. 000001af: 71 bc a4 d6 78 3f 07 00 00 TS 7969191666876
[...]
. 00000ef4: b0 44 3a fe 29 ee b7 ff c0 PC 0xffb7ee29fe3a44 el2 ns=1
. 00000efd: 99 07 00 LAT 7 ISSUE
. 00000f00: 98 08 00 LAT 8 TOT
. 00000f03: 52 82 00 EV RETIRED MISPRED
. 00000f06: 4a 01 B COND
. 00000f08: b1 20 3a fe 29 ee b7 ff c0 TGT 0xffb7ee29fe3a20 el2 ns=1
. 00000f11: 00 00 00 00 00 00 PAD
. 00000f17: 71 1e 06 d7 78 3f 07 00 00 TS 7969191691806
[...]
. 00000f20: b0 fc 87 fc 29 ee b7 ff c0 PC 0xffb7ee29fc87fc el2 ns=1
. 00000f29: 99 06 00 LAT 6 ISSUE
. 00000f2c: 98 07 00 LAT 7 TOT
. 00000f2f: 52 82 00 EV RETIRED MISPRED
. 00000f32: 4a 01 B COND
. 00000f34: b1 08 88 fc 29 ee b7 ff c0 TGT 0xffb7ee29fc8808 el2 ns=1
. 00000f3d: 00 00 00 00 00 00 PAD
. 00000f43: 71 e1 07 d7 78 3f 07 00 00 TS 7969191692257
[...]
. 00000ffc: b0 18 24 fd 29 ee b7 ff c0 PC 0xffb7ee29fd2418 el2 ns=1
. 00001005: 99 02 00 LAT 2 ISSUE
. 00001008: 98 03 00 LAT 3 TOT
. 0000100b: 52 c2 00 EV RETIRED NOT-TAKEN MISPRED
. 0000100e: 4a 01 B COND
. 00001010: b1 1c 24 fd 29 ee b7 ff c0 TGT 0xffb7ee29fd241c el2 ns=1
. 00001019: 00 00 00 00 00 00 PAD
. 0000101f: 71 e9 11 d7 78 3f 07 00 00 TS 7969191694825
[...]
. 00001188: b0 c0 e0 20 2a ee b7 ff c0 PC 0xffb7ee2a20e0c0 el2 ns=1
. 00001191: 99 02 00 LAT 2 ISSUE
. 00001194: 98 03 00 LAT 3 TOT
. 00001197: 52 c2 00 EV RETIRED NOT-TAKEN MISPRED
. 0000119a: 4a 01 B COND
. 0000119c: b1 c4 e0 20 2a ee b7 ff c0 TGT 0xffb7ee2a20e0c4 el2 ns=1
. 000011a5: 00 00 00 00 00 00 PAD
. 000011ab: 71 40 1e d7 78 3f 07 00 00 TS 7969191697984
[...]
. 00001c5c: b0 2c 8c fd 6c fd ff 00 80 PC 0xfffd6cfd8c2c el0 ns=1
. 00001c65: 99 02 00 LAT 2 ISSUE
. 00001c68: 98 03 00 LAT 3 TOT
. 00001c6b: 52 c2 00 EV RETIRED NOT-TAKEN MISPRED
. 00001c6e: 4a 01 B COND
. 00001c70: b1 30 8c fd 6c fd ff 00 80 TGT 0xfffd6cfd8c30 el0 ns=1
. 00001c79: 00 00 00 00 00 00 PAD
. 00001c7f: 71 36 03 d8 78 3f 07 00 00 TS 7969191756598
[...]
. 00001e40: b0 00 0b de 6c fd ff 00 80 PC 0xfffd6cde0b00 el0 ns=1
. 00001e49: 99 02 00 LAT 2 ISSUE
. 00001e4c: 98 03 00 LAT 3 TOT
. 00001e4f: 52 82 00 EV RETIRED MISPRED
. 00001e52: 4a 01 B COND
. 00001e54: b1 50 0b de 6c fd ff 00 80 TGT 0xfffd6cde0b50 el0 ns=1
. 00001e5d: 00 00 00 00 00 00 PAD
. 00001e63: 71 0f 1d d8 78 3f 07 00 00 TS 7969191763215
[...]
. 00002234: b0 e0 60 f3 29 ee b7 ff c0 PC 0xffb7ee29f360e0 el2 ns=1
. 0000223d: 99 02 00 LAT 2 ISSUE
. 00002240: 98 03 00 LAT 3 TOT
. 00002243: 52 82 00 EV RETIRED MISPRED
. 00002246: 4a 01 B COND
. 00002248: b1 68 61 f3 29 ee b7 ff c0 TGT 0xffb7ee29f36168 el2 ns=1
. 00002251: 00 00 00 00 00 00 PAD
. 00002257: 71 7d 27 d8 78 3f 07 00 00 TS 7969191765885
[...]
. 0000228c: b0 60 b0 fd 6c fd ff 00 80 PC 0xfffd6cfdb060 el0 ns=1
. 00002295: 99 0e 00 LAT 14 ISSUE
. 00002298: 98 0f 00 LAT 15 TOT
. 0000229b: 52 c2 00 EV RETIRED NOT-TAKEN MISPRED
. 0000229e: 4a 01 B COND
. 000022a0: b1 64 b0 fd 6c fd ff 00 80 TGT 0xfffd6cfdb064 el0 ns=1
. 000022a9: 00 00 00 00 00 00 PAD
. 000022af: 71 af 2b d8 78 3f 07 00 00 TS 7969191766959
[...]
. 00002af8: b0 28 7a fe 6c fd ff 00 80 PC 0xfffd6cfe7a28 el0 ns=1
. 00002b01: 99 03 00 LAT 3 ISSUE
. 00002b04: 98 04 00 LAT 4 TOT
. 00002b07: 52 c2 00 EV RETIRED NOT-TAKEN MISPRED
. 00002b0a: 4a 01 B COND
. 00002b0c: b1 2c 7a fe 6c fd ff 00 80 TGT 0xfffd6cfe7a2c el0 ns=1
. 00002b15: 00 00 00 00 00 00 PAD
. 00002b1b: 71 95 50 d8 78 3f 07 00 00 TS 7969191776405
[...]
. 00002b50: b0 28 7a fe 6c fd ff 00 80 PC 0xfffd6cfe7a28 el0 ns=1
. 00002b59: 99 05 00 LAT 5 ISSUE
. 00002b5c: 98 06 00 LAT 6 TOT
. 00002b5f: 52 02 00 EV RETIRED
. 00002b62: 4a 01 B COND
. 00002b64: b1 10 7a fe 6c fd ff 00 80 TGT 0xfffd6cfe7a10 el0 ns=1
. 00002b6d: 00 00 00 00 00 00 PAD
. 00002b73: 71 f3 51 d8 78 3f 07 00 00 TS 7969191776755
[...]
. 00003498: b0 30 29 e7 6c fd ff 00 80 PC 0xfffd6ce72930 el0 ns=1
. 000034a1: 99 0b 00 LAT 11 ISSUE
. 000034a4: 98 0c 00 LAT 12 TOT
. 000034a7: 52 42 00 EV RETIRED NOT-TAKEN
. 000034aa: 4a 01 B COND
. 000034ac: b1 34 29 e7 6c fd ff 00 80 TGT 0xfffd6ce72934 el0 ns=1
. 000034b5: 00 00 00 00 00 00 PAD
. 000034bb: 71 ea 86 d8 78 3f 07 00 00 TS 7969191790314
[...]
. 00003ba4: b0 78 95 fe 29 ee b7 ff c0 PC 0xffb7ee29fe9578 el2 ns=1
. 00003bad: 99 02 00 LAT 2 ISSUE
. 00003bb0: 98 03 00 LAT 3 TOT
. 00003bb3: 52 82 00 EV RETIRED MISPRED
. 00003bb6: 4a 01 B COND
. 00003bb8: b1 2c 95 fe 29 ee b7 ff c0 TGT 0xffb7ee29fe952c el2 ns=1
. 00003bc1: 00 00 00 00 00 00 PAD
. 00003bc7: 71 3a b0 d8 78 3f 07 00 00 TS 7969191800890
[...]
. 00003d04: b0 14 c0 d8 6c fd ff 00 80 PC 0xfffd6cd8c014 el0 ns=1
. 00003d0d: 99 02 00 LAT 2 ISSUE
. 00003d10: 98 03 00 LAT 3 TOT
. 00003d13: 52 82 00 EV RETIRED MISPRED
. 00003d16: 4a 01 B COND
. 00003d18: b1 e8 c0 d8 6c fd ff 00 80 TGT 0xfffd6cd8c0e8 el0 ns=1
. 00003d21: 00 00 00 00 00 00 PAD
. 00003d27: 71 51 ba d8 78 3f 07 00 00 TS 7969191803473
[...]
. 00003ff0: b0 60 0e dd 6c fd ff 00 80 PC 0xfffd6cdd0e60 el0 ns=1
. 00003ff9: 99 03 00 LAT 3 ISSUE
. 00003ffc: 98 04 00 LAT 4 TOT
. 00003fff: 52 82 00 EV RETIRED MISPRED
. 00004002: 4a 01 B COND
. 00004004: b1 d8 0e dd 6c fd ff 00 80 TGT 0xfffd6cdd0ed8 el0 ns=1
. 0000400d: 00 00 00 00 00 00 PAD
. 00004013: 71 e0 d2 d8 78 3f 07 00 00 TS 7969191809760
[...]
# perf script
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee29f38200 do_mmap+0x60 ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee2a20e10c __pi_memcpy+0x8c ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee29fe3a44 __d_lookup_rcu+0xe4 ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee29fc87fc cp_new_stat+0x11c ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee29fd2418 link_path_walk.part.35+0x198 ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee2a20e0c0 __pi_memcpy+0x40 ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cfd8c2c [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cde0b00 memset+0x18 (/usr/lib64/libc-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee29f360e0 __split_vma+0x110 ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cfdb060 [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cfe7a28 [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cfe7a28 [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6ce72930 _dl_addr+0x110 (/usr/lib64/libc-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: ffffb7ee29fe9578 atime_needs_update+0x120 ([kernel.kallsyms])
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cd8c014 [unknown] (/usr/lib64/libc-2.28.so)
ls 107690 [005] 7969.191661: 1 branch-miss: fffd6cdd0e60 [unknown] (/usr/lib64/libc-2.28.so)
Solution:
Set "sample->time" to the timestamp corresponding to each packet in auxtrace.
After:
# perf script
ls 107690 [005] 7969.191665: 1 branch-miss: ffffb7ee29f38200 do_mmap+0x60 ([kernel.kallsyms])
ls 107690 [005] 7969.191666: 1 branch-miss: ffffb7ee2a20e10c __pi_memcpy+0x8c ([kernel.kallsyms])
ls 107690 [005] 7969.191691: 1 branch-miss: ffffb7ee29fe3a44 __d_lookup_rcu+0xe4 ([kernel.kallsyms])
ls 107690 [005] 7969.191692: 1 branch-miss: ffffb7ee29fc87fc cp_new_stat+0x11c ([kernel.kallsyms])
ls 107690 [005] 7969.191694: 1 branch-miss: ffffb7ee29fd2418 link_path_walk.part.35+0x198 ([kernel.kallsyms])
ls 107690 [005] 7969.191697: 1 branch-miss: ffffb7ee2a20e0c0 __pi_memcpy+0x40 ([kernel.kallsyms])
ls 107690 [005] 7969.191756: 1 branch-miss: fffd6cfd8c2c [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191763: 1 branch-miss: fffd6cde0b00 memset+0x18 (/usr/lib64/libc-2.28.so)
ls 107690 [005] 7969.191765: 1 branch-miss: ffffb7ee29f360e0 __split_vma+0x110 ([kernel.kallsyms])
ls 107690 [005] 7969.191766: 1 branch-miss: fffd6cfdb060 [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191776: 1 branch-miss: fffd6cfe7a28 [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191782: 1 branch-miss: fffd6cfe7a28 [unknown] (/usr/lib64/ld-2.28.so)
ls 107690 [005] 7969.191791: 1 branch-miss: fffd6ce72930 _dl_addr+0x110 (/usr/lib64/libc-2.28.so)
ls 107690 [005] 7969.191800: 1 branch-miss: ffffb7ee29fe9578 atime_needs_update+0x120 ([kernel.kallsyms])
ls 107690 [005] 7969.191803: 1 branch-miss: fffd6cd8c014 [unknown] (/usr/lib64/libc-2.28.so)
ls 107690 [005] 7969.191809: 1 branch-miss: fffd6cdd0e60 [unknown] (/usr/lib64/libc-2.28.so)
Signed-off-by: Yang Jihong <redacted>
---
tools/perf/util/arm-spe.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
index 2539d4baec44..c4550cc1b248 100644
--- a/tools/perf/util/arm-spe.c
+++ b/tools/perf/util/arm-spe.c@@ -231,7 +231,7 @@ static void arm_spe_prep_sample(struct arm_spe *spe, struct arm_spe_record *record = &speq->decoder->record; if (!spe->timeless_decoding) - sample->time = speq->timestamp; + sample->time = record->timestamp; sample->ip = record->from_ip; sample->cpumode = arm_spe_cpumode(spe, sample->ip);
--
2.30.GIT
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