@@ -71,6 +71,7 @@ struct arm_spe {
u64 kernel_start;
unsigned long num_events;
+ u8 use_ctx_pkt_for_pid;
};
struct arm_spe_queue {
@@ -226,6 +227,44 @@ static inline u8 arm_spe_cpumode(struct arm_spe *spe, u64 ip)
PERF_RECORD_MISC_USER;
}
+static void arm_spe_set_pid_tid_cpu(struct arm_spe *spe,
+ struct auxtrace_queue *queue)
+{
+ struct arm_spe_queue *speq = queue->priv;
+ pid_t tid;
+
+ tid = machine__get_current_tid(spe->machine, speq->cpu);
+ if (tid != -1) {
+ speq->tid = tid;
+ thread__zput(speq->thread);
+ } else
+ speq->tid = queue->tid;
+
+ if ((!speq->thread) && (speq->tid != -1)) {
+ speq->thread = machine__find_thread(spe->machine, -1,
+ speq->tid);
+ }
+
+ if (speq->thread) {
+ speq->pid = speq->thread->pid_;
+ if (queue->cpu == -1)
+ speq->cpu = speq->thread->cpu;
+ }
+}
+
+static int arm_spe_set_tid(struct arm_spe_queue *speq, pid_t tid)
+{
+ struct arm_spe *spe = speq->spe;
+ int err = machine__set_current_tid(spe->machine, speq->cpu, -1, tid);
+
+ if (err)
+ return err;
+
+ arm_spe_set_pid_tid_cpu(spe, &spe->queues.queue_array[speq->queue_nr]);
+
+ return 0;
+}
+
static void arm_spe_prep_sample(struct arm_spe *spe,
struct arm_spe_queue *speq,
union perf_event *event,
@@ -460,6 +499,19 @@ static int arm_spe_run_decoder(struct arm_spe_queue *speq, u64 *timestamp)
* can correlate samples between Arm SPE trace data and other
* perf events with correct time ordering.
*/
+
+ /*
+ * Update pid/tid info.
+ */
+ record = &speq->decoder->record;
+ if (!spe->timeless_decoding && record->context_id != (u64)-1) {
+ ret = arm_spe_set_tid(speq, record->context_id);
+ if (ret)
+ return ret;
+
+ spe->use_ctx_pkt_for_pid = true;
+ }
+
ret = arm_spe_sample(speq);
if (ret)
return ret;
@@ -586,31 +638,6 @@ static bool arm_spe__is_timeless_decoding(struct arm_spe *spe)
return timeless_decoding;
}
-static void arm_spe_set_pid_tid_cpu(struct arm_spe *spe,
- struct auxtrace_queue *queue)
-{
- struct arm_spe_queue *speq = queue->priv;
- pid_t tid;
-
- tid = machine__get_current_tid(spe->machine, speq->cpu);
- if (tid != -1) {
- speq->tid = tid;
- thread__zput(speq->thread);
- } else
- speq->tid = queue->tid;
-
- if ((!speq->thread) && (speq->tid != -1)) {
- speq->thread = machine__find_thread(spe->machine, -1,
- speq->tid);
- }
-
- if (speq->thread) {
- speq->pid = speq->thread->pid_;
- if (queue->cpu == -1)
- speq->cpu = speq->thread->cpu;
- }
-}
-
static int arm_spe_process_queues(struct arm_spe *spe, u64 timestamp)
{
unsigned int queue_nr;
@@ -641,7 +668,12 @@ static int arm_spe_process_queues(struct arm_spe *spe, u64 timestamp)
ts = timestamp;
}
- arm_spe_set_pid_tid_cpu(spe, queue);
+ /*
+ * A previous context-switch event has set pid/tid in the machine's context, so
+ * here we need to update the pid/tid in the thread and SPE queue.
+ */
+ if (!spe->use_ctx_pkt_for_pid)
+ arm_spe_set_pid_tid_cpu(spe, queue);
ret = arm_spe_run_decoder(speq, &ts);
if (ret < 0) {
@@ -740,8 +772,9 @@ static int arm_spe_process_event(struct perf_session *session,
if (err)
return err;
- if (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE ||
- event->header.type == PERF_RECORD_SWITCH)
+ if (!spe->use_ctx_pkt_for_pid &&
+ (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE ||
+ event->header.type == PERF_RECORD_SWITCH))
err = arm_spe_context_switch(spe, event, sample);
}
@@ -808,7 +841,15 @@ static int arm_spe_flush(struct perf_session *session __maybe_unused,
return arm_spe_process_timeless_queues(spe, -1,
MAX_TIMESTAMP - 1);
- return arm_spe_process_queues(spe, MAX_TIMESTAMP);
+ ret = arm_spe_process_queues(spe, MAX_TIMESTAMP);
+ if (ret)
+ return ret;
+
+ if (!spe->use_ctx_pkt_for_pid)
+ ui__warning("Arm SPE CONTEXT packets not found in the traces.\n"
+ "Matching of TIDs to SPE events could be inaccurate.\n");
+
+ return 0;
}
static void arm_spe_free_queue(void *priv)
If Arm SPE traces contain CONTEXT packets with TID info, use these values for tracking tid of samples. Otherwise fall back to using context switch events and display a message warning the user of possible timing inaccuracies [1]. [1] https://lore.kernel.org/lkml/f877cfa6-9b25-6445-3806-ca44a4042eaf@arm.com/ Signed-off-by: German Gomez <german.gomez@arm.com> --- tools/perf/util/arm-spe.c | 99 +++++++++++++++++++++++++++------------ 1 file changed, 70 insertions(+), 29 deletions(-)