[PATCH 07/10] perf: cs-etm: Update event to read trace ID from sysfs

From: Mike Leach
Date: Tue Mar 08 2022 - 15:50:43 EST


Read the current trace ID values associated with a CPU
from sysfs.

Previously used the static association algorithm that is no longer
used as it did not scale and was broken for larger core counts.

Signed-off-by: Mike Leach <mike.leach@xxxxxxxxxx>
---
tools/perf/arch/arm/util/cs-etm.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
index 2e8b2c4365a0..f48087d07bcb 100644
--- a/tools/perf/arch/arm/util/cs-etm.c
+++ b/tools/perf/arch/arm/util/cs-etm.c
@@ -43,11 +43,13 @@ struct cs_etm_recording {
};

static const char *metadata_etmv3_ro[CS_ETM_PRIV_MAX] = {
+ [CS_ETM_ETMTRACEIDR] = "traceid",
[CS_ETM_ETMCCER] = "mgmt/etmccer",
[CS_ETM_ETMIDR] = "mgmt/etmidr",
};

static const char * const metadata_etmv4_ro[] = {
+ [CS_ETMV4_TRCTRACEIDR] = "mgmt/trctraceid",
[CS_ETMV4_TRCIDR0] = "trcidr/trcidr0",
[CS_ETMV4_TRCIDR1] = "trcidr/trcidr1",
[CS_ETMV4_TRCIDR2] = "trcidr/trcidr2",
@@ -629,8 +631,9 @@ static void cs_etm_save_etmv4_header(__u64 data[], struct auxtrace_record *itr,

/* Get trace configuration register */
data[CS_ETMV4_TRCCONFIGR] = cs_etmv4_get_config(itr);
- /* Get traceID from the framework */
- data[CS_ETMV4_TRCTRACEIDR] = coresight_get_trace_id(cpu);
+ /* Get traceID from the sysfs */
+ data[CS_ETMV4_TRCTRACEIDR] = cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv4_ro[CS_ETMV4_TRCTRACEIDR]);
/* Get read-only information from sysFS */
data[CS_ETMV4_TRCIDR0] = cs_etm_get_ro(cs_etm_pmu, cpu,
metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
@@ -677,9 +680,10 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
magic = __perf_cs_etmv3_magic;
/* Get configuration register */
info->priv[*offset + CS_ETM_ETMCR] = cs_etm_get_config(itr);
- /* Get traceID from the framework */
+ /* Get traceID from sysfs */
info->priv[*offset + CS_ETM_ETMTRACEIDR] =
- coresight_get_trace_id(cpu);
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv3_ro[CS_ETM_ETMTRACEIDR]);
/* Get read-only information from sysFS */
info->priv[*offset + CS_ETM_ETMCCER] =
cs_etm_get_ro(cs_etm_pmu, cpu,
--
2.17.1