perf: Use sample_flags for callchain

So that it can call perf_callchain() only if needed.  Historically it used
__PERF_SAMPLE_CALLCHAIN_EARLY but we can do that with sample_flags in the
struct perf_sample_data.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220908214104.3851807-1-namhyung@kernel.org

arch/x86/events/amd/ibs.c

@@ -798,8 +798,10 @@ static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs)
 	 * recorded as part of interrupt regs. Thus we need to use rip from
 	 * interrupt regs while unwinding call stack.
 	 */
-	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
+	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {
 		data.callchain = perf_callchain(event, iregs);
+		data.sample_flags |= PERF_SAMPLE_CALLCHAIN;
+	}
 
 	throttle = perf_event_overflow(event, &data, &regs);
 out:

arch/x86/events/intel/ds.c

@@ -1546,8 +1546,10 @@ static void setup_pebs_fixed_sample_data(struct perf_event *event,
 	 * previous PMI context or an (I)RET happened between the record and
 	 * PMI.
 	 */
-	if (sample_type & PERF_SAMPLE_CALLCHAIN)
+	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
 		data->callchain = perf_callchain(event, iregs);
+		data->sample_flags |= PERF_SAMPLE_CALLCHAIN;
+	}
 
 	/*
 	 * We use the interrupt regs as a base because the PEBS record does not
@@ -1719,8 +1721,10 @@ static void setup_pebs_adaptive_sample_data(struct perf_event *event,
 	 * previous PMI context or an (I)RET happened between the record and
 	 * PMI.
 	 */
-	if (sample_type & PERF_SAMPLE_CALLCHAIN)
+	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
 		data->callchain = perf_callchain(event, iregs);
+		data->sample_flags |= PERF_SAMPLE_CALLCHAIN;
+	}
 
 	*regs = *iregs;
 	/* The ip in basic is EventingIP */

kernel/events/core.c

@@ -7320,7 +7320,7 @@ void perf_prepare_sample(struct perf_event_header *header,
 	if (sample_type & PERF_SAMPLE_CALLCHAIN) {
 		int size = 1;
 
-		if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY))
+		if (filtered_sample_type & PERF_SAMPLE_CALLCHAIN)
 			data->callchain = perf_callchain(event, regs);
 
 		size += data->callchain->nr;