When using dynamically assigned CoreSight trace IDs the drivers can output the ID / CPU association as a PERF_RECORD_AUX_OUTPUT_HW_ID packet.
Update cs-etm decoder to handle this packet by setting the CPU/Trace ID mapping.
Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: James Clark james.clark@arm.com Acked-by: Suzuki K Poulose suzuki.poulose@arm.com --- tools/include/linux/coresight-pmu.h | 15 ++ .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 7 + tools/perf/util/cs-etm.c | 246 ++++++++++++++++-- 3 files changed, 250 insertions(+), 18 deletions(-)
diff --git a/tools/include/linux/coresight-pmu.h b/tools/include/linux/coresight-pmu.h index 307f357defe9..57ba1abf1224 100644 --- a/tools/include/linux/coresight-pmu.h +++ b/tools/include/linux/coresight-pmu.h @@ -32,6 +32,9 @@ */ #define CORESIGHT_TRACE_ID_UNUSED_FLAG BIT(31)
+/* Value to set for unused trace ID values */ +#define CORESIGHT_TRACE_ID_UNUSED_VAL 0x7F + /* * Below are the definition of bit offsets for perf option, and works as * arbitrary values for all ETM versions. @@ -56,4 +59,16 @@ #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/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c index 31fa3b45134a..fa3aa9c0fb2e 100644 --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c @@ -625,6 +625,7 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params, switch (t_params->protocol) { case CS_ETM_PROTO_ETMV3: case CS_ETM_PROTO_PTM: + csid = (t_params->etmv3.reg_idr & CORESIGHT_TRACE_ID_VAL_MASK); cs_etm_decoder__gen_etmv3_config(t_params, &config_etmv3); decoder->decoder_name = (t_params->protocol == CS_ETM_PROTO_ETMV3) ? OCSD_BUILTIN_DCD_ETMV3 : @@ -632,11 +633,13 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params, trace_config = &config_etmv3; break; case CS_ETM_PROTO_ETMV4i: + csid = (t_params->etmv4.reg_traceidr & CORESIGHT_TRACE_ID_VAL_MASK); cs_etm_decoder__gen_etmv4_config(t_params, &trace_config_etmv4); decoder->decoder_name = OCSD_BUILTIN_DCD_ETMV4I; trace_config = &trace_config_etmv4; break; case CS_ETM_PROTO_ETE: + csid = (t_params->ete.reg_traceidr & CORESIGHT_TRACE_ID_VAL_MASK); cs_etm_decoder__gen_ete_config(t_params, &trace_config_ete); decoder->decoder_name = OCSD_BUILTIN_DCD_ETE; trace_config = &trace_config_ete; @@ -645,6 +648,10 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params, return -1; }
+ /* if the CPU has no trace ID associated, no decoder needed */ + if (csid == CORESIGHT_TRACE_ID_UNUSED_VAL) + return 0; + if (d_params->operation == CS_ETM_OPERATION_DECODE) { if (ocsd_dt_create_decoder(decoder->dcd_tree, decoder->decoder_name, diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index f77260b9253e..51f58e7ababd 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -217,6 +217,143 @@ static int cs_etm__map_trace_id(u8 trace_chan_id, u64 *cpu_metadata) return 0; }
+static int cs_etm__metadata_get_trace_id(u8 *trace_chan_id, u64 *cpu_metadata) +{ + u64 cs_etm_magic = cpu_metadata[CS_ETM_MAGIC]; + + switch (cs_etm_magic) { + case __perf_cs_etmv3_magic: + *trace_chan_id = (u8)(cpu_metadata[CS_ETM_ETMTRACEIDR] & + CORESIGHT_TRACE_ID_VAL_MASK); + break; + case __perf_cs_etmv4_magic: + case __perf_cs_ete_magic: + *trace_chan_id = (u8)(cpu_metadata[CS_ETMV4_TRCTRACEIDR] & + CORESIGHT_TRACE_ID_VAL_MASK); + break; + default: + return -EINVAL; + } + return 0; +} + +/* + * update metadata trace ID from the value found in the AUX_HW_INFO packet. + * This will also clear the CORESIGHT_TRACE_ID_UNUSED_FLAG flag if present. + */ +static int cs_etm__metadata_set_trace_id(u8 trace_chan_id, u64 *cpu_metadata) +{ + u64 cs_etm_magic = cpu_metadata[CS_ETM_MAGIC]; + + switch (cs_etm_magic) { + case __perf_cs_etmv3_magic: + cpu_metadata[CS_ETM_ETMTRACEIDR] = trace_chan_id; + break; + case __perf_cs_etmv4_magic: + case __perf_cs_ete_magic: + cpu_metadata[CS_ETMV4_TRCTRACEIDR] = trace_chan_id; + break; + + default: + return -EINVAL; + } + return 0; +} + +/* + * FIELD_GET (linux/bitfield.h) not available outside kernel code, + * and the header contains too many dependencies to just copy over, + * so roll our own based on the original + */ +#define __bf_shf(x) (__builtin_ffsll(x) - 1) +#define FIELD_GET(_mask, _reg) \ + ({ \ + (typeof(_mask))(((_reg) & (_mask)) >> __bf_shf(_mask)); \ + }) + +/* + * Handle the PERF_RECORD_AUX_OUTPUT_HW_ID event. + * + * The payload associates the Trace ID and the CPU. + * The routine is tolerant of seeing multiple packets with the same association, + * but a CPU / Trace ID association changing during a session is an error. + */ +static int cs_etm__process_aux_output_hw_id(struct perf_session *session, + union perf_event *event) +{ + struct cs_etm_auxtrace *etm; + struct perf_sample sample; + struct int_node *inode; + struct evsel *evsel; + u64 *cpu_data; + u64 hw_id; + int cpu, version, err; + u8 trace_chan_id, curr_chan_id; + + /* extract and parse the HW ID */ + hw_id = event->aux_output_hw_id.hw_id; + version = FIELD_GET(CS_AUX_HW_ID_VERSION_MASK, hw_id); + trace_chan_id = FIELD_GET(CS_AUX_HW_ID_TRACE_ID_MASK, hw_id); + + /* check that we can handle this version */ + if (version > CS_AUX_HW_ID_CURR_VERSION) + return -EINVAL; + + /* get access to the etm metadata */ + etm = container_of(session->auxtrace, struct cs_etm_auxtrace, auxtrace); + if (!etm || !etm->metadata) + return -EINVAL; + + /* parse the sample to get the CPU */ + evsel = evlist__event2evsel(session->evlist, event); + if (!evsel) + return -EINVAL; + err = evsel__parse_sample(evsel, event, &sample); + if (err) + return err; + cpu = sample.cpu; + if (cpu == -1) { + /* no CPU in the sample - possibly recorded with an old version of perf */ + pr_err("CS_ETM: no CPU AUX_OUTPUT_HW_ID sample. Use compatible perf to record."); + return -EINVAL; + } + + /* See if the ID is mapped to a CPU, and it matches the current CPU */ + inode = intlist__find(traceid_list, trace_chan_id); + if (inode) { + cpu_data = inode->priv; + if ((int)cpu_data[CS_ETM_CPU] != cpu) { + pr_err("CS_ETM: map mismatch between HW_ID packet CPU and Trace ID\n"); + return -EINVAL; + } + + /* check that the mapped ID matches */ + err = cs_etm__metadata_get_trace_id(&curr_chan_id, cpu_data); + if (err) + return err; + if (curr_chan_id != trace_chan_id) { + pr_err("CS_ETM: mismatch between CPU trace ID and HW_ID packet ID\n"); + return -EINVAL; + } + + /* mapped and matched - return OK */ + return 0; + } + + /* not one we've seen before - lets map it */ + cpu_data = etm->metadata[cpu]; + err = cs_etm__map_trace_id(trace_chan_id, cpu_data); + if (err) + return err; + + /* + * if we are picking up the association from the packet, need to plug + * the correct trace ID into the metadata for setting up decoders later. + */ + err = cs_etm__metadata_set_trace_id(trace_chan_id, cpu_data); + return err; +} + void cs_etm__etmq_set_traceid_queue_timestamp(struct cs_etm_queue *etmq, u8 trace_chan_id) { @@ -2639,11 +2776,16 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o }
/* - * In per-thread mode, CPU is set to -1, but TID will be set instead. See - * auxtrace_mmap_params__set_idx(). Return 'not found' if neither CPU nor TID match. + * In per-thread mode, auxtrace CPU is set to -1, but TID will be set instead. See + * auxtrace_mmap_params__set_idx(). However, the sample AUX event will contain a + * CPU as we set this always for the AUX_OUTPUT_HW_ID event. + * So now compare only TIDs if auxtrace CPU is -1, and CPUs if auxtrace CPU is not -1. + * Return 'not found' if mismatch. */ - if ((auxtrace_event->cpu == (__u32) -1 && auxtrace_event->tid != sample->tid) || - auxtrace_event->cpu != sample->cpu) + if (auxtrace_event->cpu == (__u32) -1) { + if (auxtrace_event->tid != sample->tid) + return 1; + } else if (auxtrace_event->cpu != sample->cpu) return 1;
if (aux_event->flags & PERF_AUX_FLAG_OVERWRITE) { @@ -2692,6 +2834,17 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o return 1; }
+static int cs_etm__process_aux_hw_id_cb(struct perf_session *session, union perf_event *event, + u64 offset __maybe_unused, void *data __maybe_unused) +{ + /* look to handle PERF_RECORD_AUX_OUTPUT_HW_ID early to ensure decoders can be set up */ + if (event->header.type == PERF_RECORD_AUX_OUTPUT_HW_ID) { + (*(int *)data)++; /* increment found count */ + return cs_etm__process_aux_output_hw_id(session, event); + } + return 0; +} + static int cs_etm__queue_aux_records_cb(struct perf_session *session, union perf_event *event, u64 offset __maybe_unused, void *data __maybe_unused) { @@ -2781,13 +2934,13 @@ static int cs_etm__map_trace_ids_metadata(int num_cpu, u64 **metadata) cs_etm_magic = metadata[i][CS_ETM_MAGIC]; switch (cs_etm_magic) { case __perf_cs_etmv3_magic: - trace_chan_id = (u8)((metadata[i][CS_ETM_ETMTRACEIDR]) & - CORESIGHT_TRACE_ID_VAL_MASK); + metadata[i][CS_ETM_ETMTRACEIDR] &= CORESIGHT_TRACE_ID_VAL_MASK; + trace_chan_id = (u8)(metadata[i][CS_ETM_ETMTRACEIDR]); break; case __perf_cs_etmv4_magic: case __perf_cs_ete_magic: - trace_chan_id = (u8)((metadata[i][CS_ETMV4_TRCTRACEIDR]) & - CORESIGHT_TRACE_ID_VAL_MASK); + metadata[i][CS_ETMV4_TRCTRACEIDR] &= CORESIGHT_TRACE_ID_VAL_MASK; + trace_chan_id = (u8)(metadata[i][CS_ETMV4_TRCTRACEIDR]); break; default: /* unknown magic number */ @@ -2800,6 +2953,35 @@ static int cs_etm__map_trace_ids_metadata(int num_cpu, u64 **metadata) return 0; }
+/* + * If we found AUX_HW_ID packets, then set any metadata marked as unused to the + * unused value to reduce the number of unneeded decoders created. + */ +static int cs_etm__clear_unused_trace_ids_metadata(int num_cpu, u64 **metadata) +{ + u64 cs_etm_magic; + int i; + + for (i = 0; i < num_cpu; i++) { + cs_etm_magic = metadata[i][CS_ETM_MAGIC]; + switch (cs_etm_magic) { + case __perf_cs_etmv3_magic: + if (metadata[i][CS_ETM_ETMTRACEIDR] & CORESIGHT_TRACE_ID_UNUSED_FLAG) + metadata[i][CS_ETM_ETMTRACEIDR] = CORESIGHT_TRACE_ID_UNUSED_VAL; + break; + case __perf_cs_etmv4_magic: + case __perf_cs_ete_magic: + if (metadata[i][CS_ETMV4_TRCTRACEIDR] & CORESIGHT_TRACE_ID_UNUSED_FLAG) + metadata[i][CS_ETMV4_TRCTRACEIDR] = CORESIGHT_TRACE_ID_UNUSED_VAL; + break; + default: + /* unknown magic number */ + return -EINVAL; + } + } + return 0; +} + int cs_etm__process_auxtrace_info_full(union perf_event *event, struct perf_session *session) { @@ -2811,6 +2993,7 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event, int priv_size = 0; int num_cpu; int err = 0; + int aux_hw_id_found; int i, j; u64 *ptr = NULL; u64 **metadata = NULL; @@ -2943,8 +3126,43 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event, if (err) goto err_delete_thread;
- /* before aux records are queued, need to map metadata to trace IDs */ - err = cs_etm__map_trace_ids_metadata(num_cpu, metadata); + /* + * Map Trace ID values to CPU metadata. + * + * Trace metadata will always contain Trace ID values from the legacy algorithm. If the + * files has been recorded by a "new" perf updated to handle AUX_HW_ID then the metadata + * ID value will also have the CORESIGHT_TRACE_ID_UNUSED_FLAG set. + * + * The updated kernel drivers that use AUX_HW_ID to sent Trace IDs will attempt to use + * the same IDs as the old algorithm as far as is possible, unless there are clashes + * in which case a different value will be used. This means an older perf may still + * be able to record and read files generate on a newer system. + * + * For a perf able to interpret AUX_HW_ID packets we first check for the presence of + * those packets. If they are there then the values will be mapped and plugged into + * the metadata. We then set any remaining metadata values with the used flag to a + * value CORESIGHT_TRACE_ID_UNUSED_VAL - which indicates no decoder is required. + * + * If no AUX_HW_ID packets are present - which means a file recorded on an old kernel + * then we map Trace ID values to CPU directly from the metadata - clearing any unused + * flags if present. + */ + + /* first scan for AUX_OUTPUT_HW_ID records to map trace ID values to CPU metadata */ + aux_hw_id_found = 0; + err = perf_session__peek_events(session, session->header.data_offset, + session->header.data_size, + cs_etm__process_aux_hw_id_cb, &aux_hw_id_found); + if (err) + goto err_delete_thread; + + /* if HW ID found then clear any unused metadata ID values */ + if (aux_hw_id_found) + err = cs_etm__clear_unused_trace_ids_metadata(num_cpu, metadata); + /* otherwise, this is a file with metadata values only, map from metadata */ + else + err = cs_etm__map_trace_ids_metadata(num_cpu, metadata); + if (err) goto err_delete_thread;
@@ -2953,14 +3171,6 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event, goto err_delete_thread;
etm->data_queued = etm->queues.populated; - /* - * Print warning in pipe mode, see cs_etm__process_auxtrace_event() and - * cs_etm__queue_aux_fragment() for details relating to limitations. - */ - if (!etm->data_queued) - pr_warning("CS ETM warning: Coresight decode and TRBE support requires random file access.\n" - "Continuing with best effort decoding in piped mode.\n\n"); - return 0;
err_delete_thread: