| Message ID | 1541912876-20967-3-git-send-email-leo.yan@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | perf cs-etm: Add support for sample flags | expand |
On Sun, Nov 11, 2018 at 01:07:56PM +0800, Leo Yan wrote: > We have prepared the flags in the packet structure, so need to copy > the related value into sample structure thus perf tool can facilitate > sample flags. > > The PREV_PACKET contains the branch instruction flags and PACKET > actually contains the flags for next branch instruction. So this patch > is to set sample flags with 'etmq->prev_packet->flags'. > > This patch includes three fixing up for sample flags based on the > packets context: > > - If the packet is exception packet or exception return packet, update > the previous packet for exception specific flags; > - If there has TRACE_ON or TRACE_OFF packet in the middle of instruction > packets, this indicates the trace is discontinuous, so append the flag > PERF_IP_FLAG_TRACE_END to the previous packet to indicate the trace > has been ended; > - If one instruction packet is behind TRACE_OFF packet, this instruction > is restarting trace packet. So set flag PERF_IP_FLAG_TRACE_START to > TRACE_OFF packet if one, this flag isn't used by TRACE_OFF packet but > used to indicate trace restarting when generate sample. > > Signed-off-by: Leo Yan <leo.yan@linaro.org> > --- > tools/perf/util/cs-etm.c | 43 +++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 41 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c > index 455f132..afca6f3 100644 > --- a/tools/perf/util/cs-etm.c > +++ b/tools/perf/util/cs-etm.c > @@ -676,7 +676,7 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq, > sample.stream_id = etmq->etm->instructions_id; > sample.period = period; > sample.cpu = etmq->packet->cpu; > - sample.flags = 0; > + sample.flags = etmq->prev_packet->flags; > sample.insn_len = 1; > sample.cpumode = event->sample.header.misc; > > @@ -735,7 +735,7 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq) > sample.stream_id = etmq->etm->branches_id; > sample.period = 1; > sample.cpu = etmq->packet->cpu; > - sample.flags = 0; > + sample.flags = etmq->prev_packet->flags; > sample.cpumode = event->sample.header.misc; > > /* > @@ -878,6 +878,43 @@ static int cs_etm__synth_events(struct cs_etm_auxtrace *etm, > return 0; > } > > +static void cs_etm__fixup_flags(struct cs_etm_queue *etmq) > +{ > + /* > + * Decoding stream might insert one TRACE_OFF packet in the > + * middle of instruction packets, this means it doesn't > + * contain the pair packets with TRACE_OFF and TRACE_ON. > + * For this case, the instruction packet follows with > + * TRACE_OFF packet so we need to fixup prev_packet with flag > + * PERF_IP_FLAG_TRACE_BEGIN, this flag finally is used by the > + * instruction packet to generate samples. > + */ > + if (etmq->prev_packet->sample_type == CS_ETM_TRACE_OFF && > + etmq->packet->sample_type == CS_ETM_RANGE) > + etmq->prev_packet->flags = PERF_IP_FLAG_BRANCH | > + PERF_IP_FLAG_TRACE_BEGIN; > + > + if (etmq->prev_packet->sample_type == CS_ETM_RANGE) { > + /* > + * When the exception packet is inserted, update flags > + * so tell perf it is exception related branches. > + */ > + if (etmq->packet->sample_type == CS_ETM_EXCEPTION || > + etmq->packet->sample_type == CS_ETM_EXCEPTION_RET) > + etmq->prev_packet->flags = etmq->packet->flags; > + > + /* > + * The trace is discontinuous, weather this is caused by > + * TRACE_ON packet or TRACE_OFF packet is coming, if the > + * previous packet is instruction packet, simply set flag > + * PERF_IP_FLAG_TRACE_END for previous packet. > + */ > + if (etmq->packet->sample_type == CS_ETM_TRACE_ON || > + etmq->packet->sample_type == CS_ETM_TRACE_OFF) > + etmq->prev_packet->flags |= PERF_IP_FLAG_TRACE_END; > + } > +} > + I think it would be better to keep all the flag related processing in cs-etm-decoder.c so that things in cs-etm.c are only concered with dealing with perf. Look at function cs_etm__alloc_queue(), there you'll find "d_params.data = etmq". In function cs_etm_decoder__new(), decoder->data = d_params->data; This means that anywhere you have a decoder, decoder->data is an etmq. I've used this profusely in my work on CPU-wide trace scenarios. Because you're getting there ahead of me you'll need to fix the declaration of struct cs_etm_queue but that's easy. Regards, Mathieu > static int cs_etm__sample(struct cs_etm_queue *etmq) > { > struct cs_etm_auxtrace *etm = etmq->etm; > @@ -1100,6 +1137,8 @@ static int cs_etm__run_decoder(struct cs_etm_queue *etmq) > */ > break; > > + cs_etm__fixup_flags(etmq); > + > switch (etmq->packet->sample_type) { > case CS_ETM_RANGE: > /* > -- > 2.7.4 >
On Mon, 19 Nov 2018 at 16:22, Mathieu Poirier <mathieu.poirier@linaro.org> wrote: > > On Sun, Nov 11, 2018 at 01:07:56PM +0800, Leo Yan wrote: > > We have prepared the flags in the packet structure, so need to copy > > the related value into sample structure thus perf tool can facilitate > > sample flags. > > > > The PREV_PACKET contains the branch instruction flags and PACKET > > actually contains the flags for next branch instruction. So this patch > > is to set sample flags with 'etmq->prev_packet->flags'. > > > > This patch includes three fixing up for sample flags based on the > > packets context: > > > > - If the packet is exception packet or exception return packet, update > > the previous packet for exception specific flags; > > - If there has TRACE_ON or TRACE_OFF packet in the middle of instruction > > packets, this indicates the trace is discontinuous, so append the flag > > PERF_IP_FLAG_TRACE_END to the previous packet to indicate the trace > > has been ended; > > - If one instruction packet is behind TRACE_OFF packet, this instruction > > is restarting trace packet. So set flag PERF_IP_FLAG_TRACE_START to > > TRACE_OFF packet if one, this flag isn't used by TRACE_OFF packet but > > used to indicate trace restarting when generate sample. > > > > Signed-off-by: Leo Yan <leo.yan@linaro.org> > > --- > > tools/perf/util/cs-etm.c | 43 +++++++++++++++++++++++++++++++++++++++++-- > > 1 file changed, 41 insertions(+), 2 deletions(-) > > > > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c > > index 455f132..afca6f3 100644 > > --- a/tools/perf/util/cs-etm.c > > +++ b/tools/perf/util/cs-etm.c > > @@ -676,7 +676,7 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq, > > sample.stream_id = etmq->etm->instructions_id; > > sample.period = period; > > sample.cpu = etmq->packet->cpu; > > - sample.flags = 0; > > + sample.flags = etmq->prev_packet->flags; > > sample.insn_len = 1; > > sample.cpumode = event->sample.header.misc; > > > > @@ -735,7 +735,7 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq) > > sample.stream_id = etmq->etm->branches_id; > > sample.period = 1; > > sample.cpu = etmq->packet->cpu; > > - sample.flags = 0; > > + sample.flags = etmq->prev_packet->flags; > > sample.cpumode = event->sample.header.misc; > > > > /* > > @@ -878,6 +878,43 @@ static int cs_etm__synth_events(struct cs_etm_auxtrace *etm, > > return 0; > > } > > > > +static void cs_etm__fixup_flags(struct cs_etm_queue *etmq) > > +{ > > + /* > > + * Decoding stream might insert one TRACE_OFF packet in the > > + * middle of instruction packets, this means it doesn't > > + * contain the pair packets with TRACE_OFF and TRACE_ON. > > + * For this case, the instruction packet follows with > > + * TRACE_OFF packet so we need to fixup prev_packet with flag > > + * PERF_IP_FLAG_TRACE_BEGIN, this flag finally is used by the > > + * instruction packet to generate samples. > > + */ > > + if (etmq->prev_packet->sample_type == CS_ETM_TRACE_OFF && > > + etmq->packet->sample_type == CS_ETM_RANGE) > > + etmq->prev_packet->flags = PERF_IP_FLAG_BRANCH | > > + PERF_IP_FLAG_TRACE_BEGIN; > > + > > + if (etmq->prev_packet->sample_type == CS_ETM_RANGE) { > > + /* > > + * When the exception packet is inserted, update flags > > + * so tell perf it is exception related branches. > > + */ > > + if (etmq->packet->sample_type == CS_ETM_EXCEPTION || > > + etmq->packet->sample_type == CS_ETM_EXCEPTION_RET) > > + etmq->prev_packet->flags = etmq->packet->flags; > > + > > + /* > > + * The trace is discontinuous, weather this is caused by > > + * TRACE_ON packet or TRACE_OFF packet is coming, if the > > + * previous packet is instruction packet, simply set flag > > + * PERF_IP_FLAG_TRACE_END for previous packet. > > + */ > > + if (etmq->packet->sample_type == CS_ETM_TRACE_ON || > > + etmq->packet->sample_type == CS_ETM_TRACE_OFF) > > + etmq->prev_packet->flags |= PERF_IP_FLAG_TRACE_END; > > + } > > +} > > + > > I think it would be better to keep all the flag related processing in > cs-etm-decoder.c so that things in cs-etm.c are only concered with dealing with > perf. > > Look at function cs_etm__alloc_queue(), there you'll find "d_params.data = etmq". > > In function cs_etm_decoder__new(), decoder->data = d_params->data; > > This means that anywhere you have a decoder, decoder->data is an etmq. I've > used this profusely in my work on CPU-wide trace scenarios. Because you're > getting there ahead of me you'll need to fix the declaration of struct > cs_etm_queue but that's easy. I've been thinking further about this and manipulating the etmq packet and prev_packet from the cs-etm-decoder.c won't work because all we have at that time is the decoder's packet queue. My goal is to manipulate the flags in only one place - either in cs-etm.c or cs-etm-decoder.c but not in both. It might be worth trying to do the implementation in cs-etm.c since there is already a lot of packet flow intelligence happening there. > > Regards, > Mathieu > > > static int cs_etm__sample(struct cs_etm_queue *etmq) > > { > > struct cs_etm_auxtrace *etm = etmq->etm; > > @@ -1100,6 +1137,8 @@ static int cs_etm__run_decoder(struct cs_etm_queue *etmq) > > */ > > break; > > > > + cs_etm__fixup_flags(etmq); > > + > > switch (etmq->packet->sample_type) { > > case CS_ETM_RANGE: > > /* > > -- > > 2.7.4 > >
On Tue, Nov 20, 2018 at 09:53:41AM -0700, Mathieu Poirier wrote: [...] > > > +static void cs_etm__fixup_flags(struct cs_etm_queue *etmq) > > > +{ > > > + /* > > > + * Decoding stream might insert one TRACE_OFF packet in the > > > + * middle of instruction packets, this means it doesn't > > > + * contain the pair packets with TRACE_OFF and TRACE_ON. > > > + * For this case, the instruction packet follows with > > > + * TRACE_OFF packet so we need to fixup prev_packet with flag > > > + * PERF_IP_FLAG_TRACE_BEGIN, this flag finally is used by the > > > + * instruction packet to generate samples. > > > + */ > > > + if (etmq->prev_packet->sample_type == CS_ETM_TRACE_OFF && > > > + etmq->packet->sample_type == CS_ETM_RANGE) > > > + etmq->prev_packet->flags = PERF_IP_FLAG_BRANCH | > > > + PERF_IP_FLAG_TRACE_BEGIN; > > > + > > > + if (etmq->prev_packet->sample_type == CS_ETM_RANGE) { > > > + /* > > > + * When the exception packet is inserted, update flags > > > + * so tell perf it is exception related branches. > > > + */ > > > + if (etmq->packet->sample_type == CS_ETM_EXCEPTION || > > > + etmq->packet->sample_type == CS_ETM_EXCEPTION_RET) > > > + etmq->prev_packet->flags = etmq->packet->flags; > > > + > > > + /* > > > + * The trace is discontinuous, weather this is caused by > > > + * TRACE_ON packet or TRACE_OFF packet is coming, if the > > > + * previous packet is instruction packet, simply set flag > > > + * PERF_IP_FLAG_TRACE_END for previous packet. > > > + */ > > > + if (etmq->packet->sample_type == CS_ETM_TRACE_ON || > > > + etmq->packet->sample_type == CS_ETM_TRACE_OFF) > > > + etmq->prev_packet->flags |= PERF_IP_FLAG_TRACE_END; > > > + } > > > +} > > > + > > > > I think it would be better to keep all the flag related processing in > > cs-etm-decoder.c so that things in cs-etm.c are only concered with dealing with > > perf. > > > > Look at function cs_etm__alloc_queue(), there you'll find "d_params.data = etmq". > > > > In function cs_etm_decoder__new(), decoder->data = d_params->data; > > > > This means that anywhere you have a decoder, decoder->data is an etmq. I've > > used this profusely in my work on CPU-wide trace scenarios. Because you're > > getting there ahead of me you'll need to fix the declaration of struct > > cs_etm_queue but that's easy. > > I've been thinking further about this and manipulating the etmq packet > and prev_packet from the cs-etm-decoder.c won't work because all we > have at that time is the decoder's packet queue. My goal is to > manipulate the flags in only one place - either in cs-etm.c or > cs-etm-decoder.c but not in both. It might be worth trying to do the > implementation in cs-etm.c since there is already a lot of packet flow > intelligence happening there. Agree. cs-etm.c has more context info than cs-etm-decoder.c, will try to refactor in single place in cs-etm.c. [...] Thanks, Leo Yan
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index 455f132..afca6f3 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -676,7 +676,7 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq, sample.stream_id = etmq->etm->instructions_id; sample.period = period; sample.cpu = etmq->packet->cpu; - sample.flags = 0; + sample.flags = etmq->prev_packet->flags; sample.insn_len = 1; sample.cpumode = event->sample.header.misc; @@ -735,7 +735,7 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq) sample.stream_id = etmq->etm->branches_id; sample.period = 1; sample.cpu = etmq->packet->cpu; - sample.flags = 0; + sample.flags = etmq->prev_packet->flags; sample.cpumode = event->sample.header.misc; /* @@ -878,6 +878,43 @@ static int cs_etm__synth_events(struct cs_etm_auxtrace *etm, return 0; } +static void cs_etm__fixup_flags(struct cs_etm_queue *etmq) +{ + /* + * Decoding stream might insert one TRACE_OFF packet in the + * middle of instruction packets, this means it doesn't + * contain the pair packets with TRACE_OFF and TRACE_ON. + * For this case, the instruction packet follows with + * TRACE_OFF packet so we need to fixup prev_packet with flag + * PERF_IP_FLAG_TRACE_BEGIN, this flag finally is used by the + * instruction packet to generate samples. + */ + if (etmq->prev_packet->sample_type == CS_ETM_TRACE_OFF && + etmq->packet->sample_type == CS_ETM_RANGE) + etmq->prev_packet->flags = PERF_IP_FLAG_BRANCH | + PERF_IP_FLAG_TRACE_BEGIN; + + if (etmq->prev_packet->sample_type == CS_ETM_RANGE) { + /* + * When the exception packet is inserted, update flags + * so tell perf it is exception related branches. + */ + if (etmq->packet->sample_type == CS_ETM_EXCEPTION || + etmq->packet->sample_type == CS_ETM_EXCEPTION_RET) + etmq->prev_packet->flags = etmq->packet->flags; + + /* + * The trace is discontinuous, weather this is caused by + * TRACE_ON packet or TRACE_OFF packet is coming, if the + * previous packet is instruction packet, simply set flag + * PERF_IP_FLAG_TRACE_END for previous packet. + */ + if (etmq->packet->sample_type == CS_ETM_TRACE_ON || + etmq->packet->sample_type == CS_ETM_TRACE_OFF) + etmq->prev_packet->flags |= PERF_IP_FLAG_TRACE_END; + } +} + static int cs_etm__sample(struct cs_etm_queue *etmq) { struct cs_etm_auxtrace *etm = etmq->etm; @@ -1100,6 +1137,8 @@ static int cs_etm__run_decoder(struct cs_etm_queue *etmq) */ break; + cs_etm__fixup_flags(etmq); + switch (etmq->packet->sample_type) { case CS_ETM_RANGE: /*
We have prepared the flags in the packet structure, so need to copy the related value into sample structure thus perf tool can facilitate sample flags. The PREV_PACKET contains the branch instruction flags and PACKET actually contains the flags for next branch instruction. So this patch is to set sample flags with 'etmq->prev_packet->flags'. This patch includes three fixing up for sample flags based on the packets context: - If the packet is exception packet or exception return packet, update the previous packet for exception specific flags; - If there has TRACE_ON or TRACE_OFF packet in the middle of instruction packets, this indicates the trace is discontinuous, so append the flag PERF_IP_FLAG_TRACE_END to the previous packet to indicate the trace has been ended; - If one instruction packet is behind TRACE_OFF packet, this instruction is restarting trace packet. So set flag PERF_IP_FLAG_TRACE_START to TRACE_OFF packet if one, this flag isn't used by TRACE_OFF packet but used to indicate trace restarting when generate sample. Signed-off-by: Leo Yan <leo.yan@linaro.org> --- tools/perf/util/cs-etm.c | 43 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 41 insertions(+), 2 deletions(-) -- 2.7.4