Em Fri, May 24, 2019 at 11:35:07AM -0600, Mathieu Poirier escreveu: > This patch deals with timestamp packets received from the decoding library > in order to give the front end packet processing loop a handle on the time > instruction conveyed by range packets have been executed at. > > Signed-off-by: Mathieu Poirier <mathieu.poir...@linaro.org> > --- > .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 112 +++++++++++++++++- > tools/perf/util/cs-etm.c | 19 +++ > tools/perf/util/cs-etm.h | 17 +++ > 3 files changed, 144 insertions(+), 4 deletions(-) > > 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 ce85e52f989c..33e975c8d11b 100644 > --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > @@ -269,6 +269,76 @@ cs_etm_decoder__create_etm_packet_printer(struct > cs_etm_trace_params *t_params, > trace_config); > } > > +static ocsd_datapath_resp_t > +cs_etm_decoder__do_soft_timestamp(struct cs_etm_queue *etmq, > + struct cs_etm_packet_queue *packet_queue, > + const uint8_t trace_chan_id) > +{ > + /* No timestamp packet has been received, nothing to do */ > + if (!packet_queue->timestamp) > + return OCSD_RESP_CONT; > + > + packet_queue->timestamp = packet_queue->next_timestamp; > + > + /* Estimate the timestamp for the next range packet */ > + packet_queue->next_timestamp += packet_queue->instr_count; > + packet_queue->instr_count = 0; > + > + /* Tell the front end which traceid_queue needs attention */ > + cs_etm__etmq_set_traceid_queue_timestamp(etmq, trace_chan_id); > + > + return OCSD_RESP_WAIT; > +} > + > +static ocsd_datapath_resp_t > +cs_etm_decoder__do_hard_timestamp(struct cs_etm_queue *etmq, > + const ocsd_generic_trace_elem *elem, > + const uint8_t trace_chan_id) > +{ > + struct cs_etm_packet_queue *packet_queue; > + > + /* First get the packet queue for this traceID */ > + packet_queue = cs_etm__etmq_get_packet_queue(etmq, trace_chan_id); > + if (!packet_queue) > + return OCSD_RESP_FATAL_SYS_ERR; > + > + /* > + * We've seen a timestamp packet before - simply record the new value. > + * Function do_soft_timestamp() will report the value to the front end, > + * hence asking the decoder to keep decoding rather than stopping. > + */ > + if (packet_queue->timestamp) { > + packet_queue->next_timestamp = elem->timestamp; > + return OCSD_RESP_CONT; > + } > + > + /* > + * This is the first timestamp we've seen since the beginning of traces > + * or a discontinuity. Since timestamps packets are generated *after* > + * range packets have been generated, we need to estimate the time at > + * which instructions started by substracting the number of instructions > + * executed to the timestamp. > + */ > + packet_queue->timestamp = elem->timestamp - > + packet_queue->instr_count;
No need to break lines like that, in this case it even wouldn't pass the width used for the comments right above it :-) I'm fixing it up this time. Something else, all the patches in this series, so far, needed to have as the subject prefix "perf cs-etm: ...", not the generic one "perf tools: ...". I'm fixing it up as well, no need to resend. - Arnaldo > + packet_queue->next_timestamp = elem->timestamp; > + packet_queue->instr_count = 0; > + > + /* Tell the front end which traceid_queue needs attention */ > + cs_etm__etmq_set_traceid_queue_timestamp(etmq, trace_chan_id); > + > + /* Halt processing until we are being told to proceed */ > + return OCSD_RESP_WAIT; > +} > + > +static void > +cs_etm_decoder__reset_timestamp(struct cs_etm_packet_queue *packet_queue) > +{ > + packet_queue->timestamp = 0; > + packet_queue->next_timestamp = 0; > + packet_queue->instr_count = 0; > +} > + > static ocsd_datapath_resp_t > cs_etm_decoder__buffer_packet(struct cs_etm_packet_queue *packet_queue, > const u8 trace_chan_id, > @@ -310,7 +380,8 @@ cs_etm_decoder__buffer_packet(struct cs_etm_packet_queue > *packet_queue, > } > > static ocsd_datapath_resp_t > -cs_etm_decoder__buffer_range(struct cs_etm_packet_queue *packet_queue, > +cs_etm_decoder__buffer_range(struct cs_etm_queue *etmq, > + struct cs_etm_packet_queue *packet_queue, > const ocsd_generic_trace_elem *elem, > const uint8_t trace_chan_id) > { > @@ -365,6 +436,23 @@ cs_etm_decoder__buffer_range(struct cs_etm_packet_queue > *packet_queue, > > packet->last_instr_size = elem->last_instr_sz; > > + /* per-thread scenario, no need to generate a timestamp */ > + if (cs_etm__etmq_is_timeless(etmq)) > + goto out; > + > + /* > + * The packet queue is full and we haven't seen a timestamp (had we > + * seen one the packet queue wouldn't be full). Let the front end > + * deal with it. > + */ > + if (ret == OCSD_RESP_WAIT) > + goto out; > + > + packet_queue->instr_count += elem->num_instr_range; > + /* Tell the front end we have a new timestamp to process */ > + ret = cs_etm_decoder__do_soft_timestamp(etmq, packet_queue, > + trace_chan_id); > +out: > return ret; > } > > @@ -372,6 +460,11 @@ static ocsd_datapath_resp_t > cs_etm_decoder__buffer_discontinuity(struct cs_etm_packet_queue *queue, > const uint8_t trace_chan_id) > { > + /* > + * Something happened and who knows when we'll get new traces so > + * reset time statistics. > + */ > + cs_etm_decoder__reset_timestamp(queue); > return cs_etm_decoder__buffer_packet(queue, trace_chan_id, > CS_ETM_DISCONTINUITY); > } > @@ -404,6 +497,7 @@ cs_etm_decoder__buffer_exception_ret(struct > cs_etm_packet_queue *queue, > > static ocsd_datapath_resp_t > cs_etm_decoder__set_tid(struct cs_etm_queue *etmq, > + struct cs_etm_packet_queue *packet_queue, > const ocsd_generic_trace_elem *elem, > const uint8_t trace_chan_id) > { > @@ -417,6 +511,12 @@ cs_etm_decoder__set_tid(struct cs_etm_queue *etmq, > if (cs_etm__etmq_set_tid(etmq, tid, trace_chan_id)) > return OCSD_RESP_FATAL_SYS_ERR; > > + /* > + * A timestamp is generated after a PE_CONTEXT element so make sure > + * to rely on that coming one. > + */ > + cs_etm_decoder__reset_timestamp(packet_queue); > + > return OCSD_RESP_CONT; > } > > @@ -446,7 +546,7 @@ static ocsd_datapath_resp_t > cs_etm_decoder__gen_trace_elem_printer( > trace_chan_id); > break; > case OCSD_GEN_TRC_ELEM_INSTR_RANGE: > - resp = cs_etm_decoder__buffer_range(packet_queue, elem, > + resp = cs_etm_decoder__buffer_range(etmq, packet_queue, elem, > trace_chan_id); > break; > case OCSD_GEN_TRC_ELEM_EXCEPTION: > @@ -457,11 +557,15 @@ static ocsd_datapath_resp_t > cs_etm_decoder__gen_trace_elem_printer( > resp = cs_etm_decoder__buffer_exception_ret(packet_queue, > trace_chan_id); > break; > + case OCSD_GEN_TRC_ELEM_TIMESTAMP: > + resp = cs_etm_decoder__do_hard_timestamp(etmq, elem, > + trace_chan_id); > + break; > case OCSD_GEN_TRC_ELEM_PE_CONTEXT: > - resp = cs_etm_decoder__set_tid(etmq, elem, trace_chan_id); > + resp = cs_etm_decoder__set_tid(etmq, packet_queue, > + elem, trace_chan_id); > break; > case OCSD_GEN_TRC_ELEM_ADDR_NACC: > - case OCSD_GEN_TRC_ELEM_TIMESTAMP: > case OCSD_GEN_TRC_ELEM_CYCLE_COUNT: > case OCSD_GEN_TRC_ELEM_ADDR_UNKNOWN: > case OCSD_GEN_TRC_ELEM_EVENT: > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c > index 17adf554b679..91496a3a2209 100644 > --- a/tools/perf/util/cs-etm.c > +++ b/tools/perf/util/cs-etm.c > @@ -80,6 +80,7 @@ struct cs_etm_queue { > struct cs_etm_decoder *decoder; > struct auxtrace_buffer *buffer; > unsigned int queue_nr; > + u8 pending_timestamp; > u64 offset; > const unsigned char *buf; > size_t buf_len, buf_used; > @@ -133,6 +134,19 @@ int cs_etm__get_cpu(u8 trace_chan_id, int *cpu) > return 0; > } > > +void cs_etm__etmq_set_traceid_queue_timestamp(struct cs_etm_queue *etmq, > + u8 trace_chan_id) > +{ > + /* > + * Wnen a timestamp packet is encountered the backend code > + * is stopped so that the front end has time to process packets > + * that were accumulated in the traceID queue. Since there can > + * be more than one channel per cs_etm_queue, we need to specify > + * what traceID queue needs servicing. > + */ > + etmq->pending_timestamp = trace_chan_id; > +} > + > static void cs_etm__clear_packet_queue(struct cs_etm_packet_queue *queue) > { > int i; > @@ -942,6 +956,11 @@ int cs_etm__etmq_set_tid(struct cs_etm_queue *etmq, > return 0; > } > > +bool cs_etm__etmq_is_timeless(struct cs_etm_queue *etmq) > +{ > + return !!etmq->etm->timeless_decoding; > +} > + > static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq, > struct cs_etm_traceid_queue *tidq, > u64 addr, u64 period) > diff --git a/tools/perf/util/cs-etm.h b/tools/perf/util/cs-etm.h > index b2a7628620bf..33b57e748c3d 100644 > --- a/tools/perf/util/cs-etm.h > +++ b/tools/perf/util/cs-etm.h > @@ -150,6 +150,9 @@ struct cs_etm_packet_queue { > u32 packet_count; > u32 head; > u32 tail; > + u32 instr_count; > + u64 timestamp; > + u64 next_timestamp; > struct cs_etm_packet packet_buffer[CS_ETM_PACKET_MAX_BUFFER]; > }; > > @@ -183,6 +186,9 @@ int cs_etm__process_auxtrace_info(union perf_event *event, > int cs_etm__get_cpu(u8 trace_chan_id, int *cpu); > int cs_etm__etmq_set_tid(struct cs_etm_queue *etmq, > pid_t tid, u8 trace_chan_id); > +bool cs_etm__etmq_is_timeless(struct cs_etm_queue *etmq); > +void cs_etm__etmq_set_traceid_queue_timestamp(struct cs_etm_queue *etmq, > + u8 trace_chan_id); > struct cs_etm_packet_queue > *cs_etm__etmq_get_packet_queue(struct cs_etm_queue *etmq, u8 trace_chan_id); > #else > @@ -207,6 +213,17 @@ static inline int cs_etm__etmq_set_tid( > return -1; > } > > +static inline bool cs_etm__etmq_is_timeless( > + struct cs_etm_queue *etmq __maybe_unused) > +{ > + /* What else to return? */ > + return true; > +} > + > +static inline void cs_etm__etmq_set_traceid_queue_timestamp( > + struct cs_etm_queue *etmq __maybe_unused, > + u8 trace_chan_id __maybe_unused) {} > + > static inline struct cs_etm_packet_queue *cs_etm__etmq_get_packet_queue( > struct cs_etm_queue *etmq __maybe_unused, > u8 trace_chan_id __maybe_unused) > -- > 2.17.1 -- - Arnaldo