| Message ID | 20230116124928.5440-14-mike.leach@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | coresight: Add new API to allocate trace source ID values | expand |
Hi Mike On 16/01/2023 12:49, Mike Leach wrote: > 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> > --- > drivers/hwtracing/coresight/coresight-etm-perf.c | 7 +++++++ > include/linux/coresight-pmu.h | 14 ++++++++++++++ > 2 files changed, 21 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c > index bdb9ab86173a..12fff661456e 100644 > --- 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); > + One minor nit: This ends up putting the HWID packet for every single time the event is scheduled on the CPU and thus we have : $ perf report -D | grep OUTPUT_HW_ID ... AUX_OUTPUT_HW_ID events: 55 (18.3%) We could do the above step only once per CPU for the lifetime of the event by book keeping the info in event_data. With that we get, one record per CPU and: $ perf report -D | grep OUTPUT_HW_ID ... AUX_OUTPUT_HW_ID events: 5 ( 1.9%) Here is a quick patch. We can queue this separately if you all are Ok with this. Thoughts ? ---8>--- diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 12fff661456e..5335f3a2b010 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -495,10 +495,16 @@ 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); + /* + * output cpu / trace ID in perf record, once for the lifetime + * of the event. + */ + if (!cpumask_test_cpu(cpu, &event_data->aux_hwid_done)) { + cpumask_set_cpu(cpu, &event_data->aux_hwid_done); + 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 */ diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h index 468f7799ab4f..9b11bb3d96d9 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.h +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h @@ -55,6 +55,7 @@ struct etm_filters { struct etm_event_data { struct work_struct work; cpumask_t mask; + cpumask_t aux_hwid_done; void *snk_config; u32 cfg_hash; struct list_head * __percpu *path; > 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 624f4843453e..51ac441a37c3 100644 > --- 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
Hi Suzuki On Thu, 19 Jan 2023 at 11:02, Suzuki K Poulose <suzuki.poulose@arm.com> wrote: > > Hi Mike > > On 16/01/2023 12:49, Mike Leach wrote: > > 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> > > --- > > drivers/hwtracing/coresight/coresight-etm-perf.c | 7 +++++++ > > include/linux/coresight-pmu.h | 14 ++++++++++++++ > > 2 files changed, 21 insertions(+) > > > > diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c > > index bdb9ab86173a..12fff661456e 100644 > > --- 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); > > + > > One minor nit: > > This ends up putting the HWID packet for every single time the event is > scheduled on the CPU and thus we have : > > $ perf report -D | grep OUTPUT_HW_ID > ... > AUX_OUTPUT_HW_ID events: 55 (18.3%) > > We could do the above step only once per CPU for the lifetime of the > event by book keeping the info in event_data. With that we get, one > record per CPU and: > > $ perf report -D | grep OUTPUT_HW_ID > ... > AUX_OUTPUT_HW_ID events: 5 ( 1.9%) > > Here is a quick patch. We can queue this separately if you all are Ok > with this. Thoughts ? > Seems reasonable given we guarantee the ID <=> CPU association for the lifetime of the perf session. Regards Mike > ---8>--- > > diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c > b/drivers/hwtracing/coresight/coresight-etm-perf.c > index 12fff661456e..5335f3a2b010 100644 > --- a/drivers/hwtracing/coresight/coresight-etm-perf.c > +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c > @@ -495,10 +495,16 @@ 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); > + /* > + * output cpu / trace ID in perf record, once for the lifetime > + * of the event. > + */ > + if (!cpumask_test_cpu(cpu, &event_data->aux_hwid_done)) { > + cpumask_set_cpu(cpu, &event_data->aux_hwid_done); > + 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 */ > diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h > b/drivers/hwtracing/coresight/coresight-etm-perf.h > index 468f7799ab4f..9b11bb3d96d9 100644 > --- a/drivers/hwtracing/coresight/coresight-etm-perf.h > +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h > @@ -55,6 +55,7 @@ struct etm_filters { > struct etm_event_data { > struct work_struct work; > cpumask_t mask; > + cpumask_t aux_hwid_done; > void *snk_config; > u32 cfg_hash; > struct list_head * __percpu *path; > > > > > 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 624f4843453e..51ac441a37c3 100644 > > --- 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 >
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index bdb9ab86173a..12fff661456e 100644 --- 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 624f4843453e..51ac441a37c3 100644 --- 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