perf cs-etm: Optimize copying last branches

If an instruction range packet can generate multiple instruction
samples, these samples share the same last branches; it's not necessary
to copy the same last branches repeatedly for these samples within the
same packet.

This patch moves out the last branches copying from function
cs_etm__synth_instruction_sample(), and execute it prior to generating
instruction samples.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20200219021811.20067-5-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Leo Yan 2020-02-19 10:18:10 +08:00 committed by Arnaldo Carvalho de Melo
parent c9f5baa136
commit 695378b567

View File

@ -1151,10 +1151,8 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->packet, &sample);
if (etm->synth_opts.last_branch) {
cs_etm__copy_last_branch_rb(etmq, tidq);
if (etm->synth_opts.last_branch)
sample.branch_stack = tidq->last_branch;
}
if (etm->synth_opts.inject) {
ret = cs_etm__inject_event(event, &sample,
@ -1431,6 +1429,10 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
u64 offset = etm->instructions_sample_period - instrs_prev;
u64 addr;
/* Prepare last branches for instruction sample */
if (etm->synth_opts.last_branch)
cs_etm__copy_last_branch_rb(etmq, tidq);
while (tidq->period_instructions >=
etm->instructions_sample_period) {
/*
@ -1508,6 +1510,11 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
if (etmq->etm->synth_opts.last_branch &&
tidq->prev_packet->sample_type == CS_ETM_RANGE) {
u64 addr;
/* Prepare last branches for instruction sample */
cs_etm__copy_last_branch_rb(etmq, tidq);
/*
* Generate a last branch event for the branches left in the
* circular buffer at the end of the trace.
@ -1515,7 +1522,7 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
* Use the address of the end of the last reported execution
* range
*/
u64 addr = cs_etm__last_executed_instr(tidq->prev_packet);
addr = cs_etm__last_executed_instr(tidq->prev_packet);
err = cs_etm__synth_instruction_sample(
etmq, tidq, addr,
@ -1560,11 +1567,16 @@ static int cs_etm__end_block(struct cs_etm_queue *etmq,
*/
if (etmq->etm->synth_opts.last_branch &&
tidq->prev_packet->sample_type == CS_ETM_RANGE) {
u64 addr;
/* Prepare last branches for instruction sample */
cs_etm__copy_last_branch_rb(etmq, tidq);
/*
* Use the address of the end of the last reported execution
* range.
*/
u64 addr = cs_etm__last_executed_instr(tidq->prev_packet);
addr = cs_etm__last_executed_instr(tidq->prev_packet);
err = cs_etm__synth_instruction_sample(
etmq, tidq, addr,