From 4d0f4ca273aa95bf592b8bad3c619b5766c8ecc7 Mon Sep 17 00:00:00 2001 From: Leo Yan Date: Thu, 19 Nov 2020 23:24:36 +0800 Subject: [PATCH] perf arm-spe: Remove size condition checking for events 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 Signed-off-by: Leo Yan Reviewed-by: Andre Przywara Acked-by: Will Deacon Cc: Alexander Shishkin Cc: Al Grant Cc: Arnaldo Carvalho de Melo Cc: Dave Martin Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Mark Rutland Cc: Mathieu Poirier Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wei Li Link: https://lore.kernel.org/r/20201119152441.6972-12-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/arm-spe-decoder/arm-spe-decoder.c | 9 +++------ tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c | 14 ++++++-------- 2 files changed, 9 insertions(+), 14 deletions(-) diff --git a/tools/perf/util/arm-spe-decoder/arm-spe-decoder.c b/tools/perf/util/arm-spe-decoder/arm-spe-decoder.c index cac2ef7..90d575c 100644 --- a/tools/perf/util/arm-spe-decoder/arm-spe-decoder.c +++ b/tools/perf/util/arm-spe-decoder/arm-spe-decoder.c @@ -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)) diff --git a/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c b/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c index 3f30b29..88bcf7e 100644 --- a/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c +++ b/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c @@ -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"); - } + 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; } -- 2.7.4