[PATCH 43/44] perf tools: Intel BTS to always update thread stack trace number

From: Adrian Hunter
Date: Thu Apr 09 2015 - 11:58:44 EST


The enhanced thread stack is used by higher layers but still
requires the trace number. The trace number is used to
distinguish discontinuous sections of trace (for example
from Snapshot mode or Sample mode), which cause the thread
stack to be flushed.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
tools/perf/util/intel-bts.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/intel-bts.c b/tools/perf/util/intel-bts.c
index a2ac54a..8eb7dba 100644
--- a/tools/perf/util/intel-bts.c
+++ b/tools/perf/util/intel-bts.c
@@ -28,6 +28,8 @@
#include "session.h"
#include "color.h"
#include "util.h"
+#include "thread.h"
+#include "thread-stack.h"
#include "pmu.h"
#include "debug.h"
#include "tsc.h"
@@ -468,19 +470,22 @@ static int intel_bts_process_buffer(struct intel_bts_queue *btsq,

static int intel_bts_process_queue(struct intel_bts_queue *btsq, u64 *timestamp)
{
- struct auxtrace_buffer *buffer = btsq->buffer;
+ struct auxtrace_buffer *buffer = btsq->buffer, *old_buffer = buffer;
struct auxtrace_queue *queue;
+ struct thread *thread;
int err;

if (btsq->done)
return 1;

if (btsq->pid == -1) {
- struct thread *thread;
-
- thread = machine__find_thread(btsq->bts->machine, -1, btsq->tid);
+ thread = machine__find_thread(btsq->bts->machine, -1,
+ btsq->tid);
if (thread)
btsq->pid = thread->pid_;
+ } else {
+ thread = machine__findnew_thread(btsq->bts->machine, btsq->pid,
+ btsq->tid);
}

queue = &btsq->bts->queues.queue_array[btsq->queue_nr];
@@ -510,6 +515,11 @@ static int intel_bts_process_queue(struct intel_bts_queue *btsq, u64 *timestamp)
intel_bts_do_fix_overlap(queue, buffer))
return -ENOMEM;

+ if (!btsq->bts->synth_opts.callchain && thread &&
+ (!old_buffer || btsq->bts->sampling_mode ||
+ (btsq->bts->snapshot_mode && !buffer->consecutive)))
+ thread_stack__set_trace_nr(thread, buffer->buffer_nr + 1);
+
err = intel_bts_process_buffer(btsq, buffer);

auxtrace_buffer__drop_data(buffer);
--
1.9.1

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