coresight: events: PERF_RECORD_AUX_OUTPUT_HW_ID used for Trace ID

Use the perf_report_aux_output_id() call to output the CoreSight trace ID
and associated CPU as a PERF_RECORD_AUX_OUTPUT_HW_ID record in the
perf.data file.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230116124928.5440-14-mike.leach@linaro.org

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index bdb9ab86173a4d0a39a57d455de7b60ff124c985..12fff661456ef7fd6e4a505fd36701a6c31c8ff2 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -4,6 +4,7 @@
  * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
  */
 
+#include <linux/bitfield.h>
 #include <linux/coresight.h>
 #include <linux/coresight-pmu.h>
 #include <linux/cpumask.h>
@@ -448,6 +449,7 @@ static void etm_event_start(struct perf_event *event, int flags)
        struct perf_output_handle *handle = &ctxt->handle;
        struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
        struct list_head *path;
+       u64 hw_id;
 
        if (!csdev)
                goto fail;
@@ -493,6 +495,11 @@ static void etm_event_start(struct perf_event *event, int flags)
        if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
                goto fail_disable_path;
 
+       /* output cpu / trace ID in perf record */
+       hw_id = FIELD_PREP(CS_AUX_HW_ID_VERSION_MASK, CS_AUX_HW_ID_CURR_VERSION);
+       hw_id |= FIELD_PREP(CS_AUX_HW_ID_TRACE_ID_MASK, coresight_trace_id_read_cpu_id(cpu));
+       perf_report_aux_output_id(event, hw_id);
+
 out:
        /* Tell the perf core the event is alive */
        event->hw.state = 0;

diff --git a/include/linux/coresight-pmu.h b/include/linux/coresight-pmu.h
index 624f4843453ea31bef925c2ad0bc89e779fa5a5f..51ac441a37c3e38ff325896199bd3af3ff79438a 100644 (file)
--- a/include/linux/coresight-pmu.h
+++ b/include/linux/coresight-pmu.h
@@ -7,6 +7,8 @@
 #ifndef _LINUX_CORESIGHT_PMU_H
 #define _LINUX_CORESIGHT_PMU_H
 
+#include <linux/bits.h>
+
 #define CORESIGHT_ETM_PMU_NAME "cs_etm"
 
 /*
@@ -43,4 +45,16 @@
 #define ETM4_CFG_BIT_RETSTK    12
 #define ETM4_CFG_BIT_VMID_OPT  15
 
+/*
+ * Interpretation of the PERF_RECORD_AUX_OUTPUT_HW_ID payload.
+ * Used to associate a CPU with the CoreSight Trace ID.
+ * [07:00] - Trace ID - uses 8 bits to make value easy to read in file.
+ * [59:08] - Unused (SBZ)
+ * [63:60] - Version
+ */
+#define CS_AUX_HW_ID_TRACE_ID_MASK     GENMASK_ULL(7, 0)
+#define CS_AUX_HW_ID_VERSION_MASK      GENMASK_ULL(63, 60)
+
+#define CS_AUX_HW_ID_CURR_VERSION 0
+
 #endif