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perf arm-spe: Remove size condition checking for events

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In the Armv8 ARM (ARM DDI 0487F.c), chapter "D10.2.6 Events packet", it
describes the event bit is valid with specific payload requirement.  For
example, the Last Level cache access event, the bit is defined as:

  E[8], byte 1 bit [0], when SZ == 0b01 , when SZ == 0b10 ,
  		     or when SZ == 0b11

It requires the payload size is at least 2 bytes, when byte 1 (start
counting from 0) is valid, E[8] (bit 0 in byte 1) can be used for LLC
access event type.  For safety, the code checks the condition for
payload size firstly, if meet the requirement for payload size, then
continue to parse event type.

If review function arm_spe_get_payload(), it has used cast, so any bytes
beyond the valid size have been set to zeros.

For this reason, we don't need to check payload size anymore afterwards
when parse events, thus this patch removes payload size conditions.

Suggested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Al Grant <Al.Grant@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wei Li <liwei391@huawei.com>
Link: https://lore.kernel.org/r/20201119152441.6972-12-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Leo Yan 2020-11-19 23:24:36 +08:00 committed by Arnaldo Carvalho de Melo
parent 889d1a675f
commit 4d0f4ca273
2 changed files with 9 additions and 14 deletions
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9
tools/perf/util/arm-spe-decoder/arm-spe-decoder.c
View File

@ -192,16 +192,13 @@ static int arm_spe_read_record(struct arm_spe_decoder *decoder)
if (payload & BIT(EV_TLB_ACCESS))
decoder->record.type |= ARM_SPE_TLB_ACCESS;
if ((idx == 2 || idx == 4 || idx == 8) &&
(payload & BIT(EV_LLC_MISS)))
if (payload & BIT(EV_LLC_MISS))
decoder->record.type |= ARM_SPE_LLC_MISS;
if ((idx == 2 || idx == 4 || idx == 8) &&
(payload & BIT(EV_LLC_ACCESS)))
if (payload & BIT(EV_LLC_ACCESS))
decoder->record.type |= ARM_SPE_LLC_ACCESS;
if ((idx == 2 || idx == 4 || idx == 8) &&
(payload & BIT(EV_REMOTE_ACCESS)))
if (payload & BIT(EV_REMOTE_ACCESS))
decoder->record.type |= ARM_SPE_REMOTE_ACCESS;
if (payload & BIT(EV_MISPRED))

2
tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c
View File

@ -311,14 +311,12 @@ static int arm_spe_pkt_desc_event(const struct arm_spe_pkt *packet,
arm_spe_pkt_out_string(&err, &buf, &buf_len, " NOT-TAKEN");
if (payload & BIT(EV_MISPRED))
arm_spe_pkt_out_string(&err, &buf, &buf_len, " MISPRED");
if (packet->index > 1) {
if (payload & BIT(EV_LLC_ACCESS))
arm_spe_pkt_out_string(&err, &buf, &buf_len, " LLC-ACCESS");
if (payload & BIT(EV_LLC_MISS))
arm_spe_pkt_out_string(&err, &buf, &buf_len, " LLC-REFILL");
if (payload & BIT(EV_REMOTE_ACCESS))
arm_spe_pkt_out_string(&err, &buf, &buf_len, " REMOTE-ACCESS");
}
return err;
}