summaryrefslogtreecommitdiff
path: root/tools/perf/util/cs-etm.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/perf/util/cs-etm.c')
-rw-r--r--tools/perf/util/cs-etm.c159
1 files changed, 113 insertions, 46 deletions
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 5471045ebf5c..62d2f9b9ce1b 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -363,6 +363,23 @@ struct cs_etm_packet_queue
return NULL;
}
+static void cs_etm__packet_swap(struct cs_etm_auxtrace *etm,
+ struct cs_etm_traceid_queue *tidq)
+{
+ struct cs_etm_packet *tmp;
+
+ if (etm->sample_branches || etm->synth_opts.last_branch ||
+ etm->sample_instructions) {
+ /*
+ * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
+ * the next incoming packet.
+ */
+ tmp = tidq->packet;
+ tidq->packet = tidq->prev_packet;
+ tidq->prev_packet = tmp;
+ }
+}
+
static void cs_etm__packet_dump(const char *pkt_string)
{
const char *color = PERF_COLOR_BLUE;
@@ -945,7 +962,7 @@ static inline u64 cs_etm__instr_addr(struct cs_etm_queue *etmq,
if (packet->isa == CS_ETM_ISA_T32) {
u64 addr = packet->start_addr;
- while (offset > 0) {
+ while (offset) {
addr += cs_etm__t32_instr_size(etmq,
trace_chan_id, addr);
offset--;
@@ -1134,10 +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,
@@ -1153,9 +1168,6 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
"CS ETM Trace: failed to deliver instruction event, error %d\n",
ret);
- if (etm->synth_opts.last_branch)
- cs_etm__reset_last_branch_rb(tidq);
-
return ret;
}
@@ -1172,6 +1184,7 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq,
union perf_event *event = tidq->event_buf;
struct dummy_branch_stack {
u64 nr;
+ u64 hw_idx;
struct branch_entry entries;
} dummy_bs;
u64 ip;
@@ -1202,6 +1215,7 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq,
if (etm->synth_opts.last_branch) {
dummy_bs = (struct dummy_branch_stack){
.nr = 1,
+ .hw_idx = -1ULL,
.entries = {
.from = sample.ip,
.to = sample.addr,
@@ -1340,12 +1354,14 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
struct cs_etm_traceid_queue *tidq)
{
struct cs_etm_auxtrace *etm = etmq->etm;
- struct cs_etm_packet *tmp;
int ret;
u8 trace_chan_id = tidq->trace_chan_id;
- u64 instrs_executed = tidq->packet->instr_count;
+ u64 instrs_prev;
+
+ /* Get instructions remainder from previous packet */
+ instrs_prev = tidq->period_instructions;
- tidq->period_instructions += instrs_executed;
+ tidq->period_instructions += tidq->packet->instr_count;
/*
* Record a branch when the last instruction in
@@ -1363,26 +1379,80 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
* TODO: allow period to be defined in cycles and clock time
*/
- /* Get number of instructions executed after the sample point */
- u64 instrs_over = tidq->period_instructions -
- etm->instructions_sample_period;
+ /*
+ * Below diagram demonstrates the instruction samples
+ * generation flows:
+ *
+ * Instrs Instrs Instrs Instrs
+ * Sample(n) Sample(n+1) Sample(n+2) Sample(n+3)
+ * | | | |
+ * V V V V
+ * --------------------------------------------------
+ * ^ ^
+ * | |
+ * Period Period
+ * instructions(Pi) instructions(Pi')
+ *
+ * | |
+ * \---------------- -----------------/
+ * V
+ * tidq->packet->instr_count
+ *
+ * Instrs Sample(n...) are the synthesised samples occurring
+ * every etm->instructions_sample_period instructions - as
+ * defined on the perf command line. Sample(n) is being the
+ * last sample before the current etm packet, n+1 to n+3
+ * samples are generated from the current etm packet.
+ *
+ * tidq->packet->instr_count represents the number of
+ * instructions in the current etm packet.
+ *
+ * Period instructions (Pi) contains the the number of
+ * instructions executed after the sample point(n) from the
+ * previous etm packet. This will always be less than
+ * etm->instructions_sample_period.
+ *
+ * When generate new samples, it combines with two parts
+ * instructions, one is the tail of the old packet and another
+ * is the head of the new coming packet, to generate
+ * sample(n+1); sample(n+2) and sample(n+3) consume the
+ * instructions with sample period. After sample(n+3), the rest
+ * instructions will be used by later packet and it is assigned
+ * to tidq->period_instructions for next round calculation.
+ */
/*
- * Calculate the address of the sampled instruction (-1 as
- * sample is reported as though instruction has just been
- * executed, but PC has not advanced to next instruction)
+ * Get the initial offset into the current packet instructions;
+ * entry conditions ensure that instrs_prev is less than
+ * etm->instructions_sample_period.
*/
- u64 offset = (instrs_executed - instrs_over - 1);
- u64 addr = cs_etm__instr_addr(etmq, trace_chan_id,
- tidq->packet, offset);
+ u64 offset = etm->instructions_sample_period - instrs_prev;
+ u64 addr;
- ret = cs_etm__synth_instruction_sample(
- etmq, tidq, addr, etm->instructions_sample_period);
- if (ret)
- return ret;
+ /* Prepare last branches for instruction sample */
+ if (etm->synth_opts.last_branch)
+ cs_etm__copy_last_branch_rb(etmq, tidq);
- /* Carry remaining instructions into next sample period */
- tidq->period_instructions = instrs_over;
+ while (tidq->period_instructions >=
+ etm->instructions_sample_period) {
+ /*
+ * Calculate the address of the sampled instruction (-1
+ * as sample is reported as though instruction has just
+ * been executed, but PC has not advanced to next
+ * instruction)
+ */
+ addr = cs_etm__instr_addr(etmq, trace_chan_id,
+ tidq->packet, offset - 1);
+ ret = cs_etm__synth_instruction_sample(
+ etmq, tidq, addr,
+ etm->instructions_sample_period);
+ if (ret)
+ return ret;
+
+ offset += etm->instructions_sample_period;
+ tidq->period_instructions -=
+ etm->instructions_sample_period;
+ }
}
if (etm->sample_branches) {
@@ -1404,15 +1474,7 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
}
}
- if (etm->sample_branches || etm->synth_opts.last_branch) {
- /*
- * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
- * the next incoming packet.
- */
- tmp = tidq->packet;
- tidq->packet = tidq->prev_packet;
- tidq->prev_packet = tmp;
- }
+ cs_etm__packet_swap(etm, tidq);
return 0;
}
@@ -1441,7 +1503,6 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
{
int err = 0;
struct cs_etm_auxtrace *etm = etmq->etm;
- struct cs_etm_packet *tmp;
/* Handle start tracing packet */
if (tidq->prev_packet->sample_type == CS_ETM_EMPTY)
@@ -1449,6 +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.
@@ -1456,7 +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,
@@ -1476,15 +1542,11 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
}
swap_packet:
- if (etm->sample_branches || etm->synth_opts.last_branch) {
- /*
- * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
- * the next incoming packet.
- */
- tmp = tidq->packet;
- tidq->packet = tidq->prev_packet;
- tidq->prev_packet = tmp;
- }
+ cs_etm__packet_swap(etm, tidq);
+
+ /* Reset last branches after flush the trace */
+ if (etm->synth_opts.last_branch)
+ cs_etm__reset_last_branch_rb(tidq);
return err;
}
@@ -1505,11 +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,
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-12 01:54:39 +0300