perf report: Display arch specific diagnostic counter sets, starting with s390

On s390 the event bc000 (also named CF_DIAG) extracts the CPU
Measurement Facility diagnostic counter sets and displays them as
counter number and counter value pairs sorted by counter set number.

Output:
 [root@s35lp76 perf]# ./perf report -D --stdio

 [00000000] Counterset:0 Counters:6
   Counter:000 Value:0x000000000085ec36 Counter:001 Value:0x0000000000796c94
   Counter:002 Value:0x0000000000005ada Counter:003 Value:0x0000000000092460
   Counter:004 Value:0x0000000000006073 Counter:005 Value:0x00000000001a9a73
 [0x000038] Counterset:1 Counters:2
   Counter:000 Value:0x000000000007c59f Counter:001 Value:0x000000000002fad6
 [0x000050] Counterset:2 Counters:16
   Counter:000 Value:000000000000000000 Counter:001 Value:000000000000000000
   Counter:002 Value:000000000000000000 Counter:003 Value:000000000000000000
   Counter:004 Value:000000000000000000 Counter:005 Value:000000000000000000
   Counter:006 Value:000000000000000000 Counter:007 Value:000000000000000000
   Counter:008 Value:000000000000000000 Counter:009 Value:000000000000000000
   Counter:010 Value:000000000000000000 Counter:011 Value:000000000000000000
   Counter:012 Value:000000000000000000 Counter:013 Value:000000000000000000
   Counter:014 Value:000000000000000000 Counter:015 Value:000000000000000000
 [0x0000d8] Counterset:3 Counters:128
   Counter:000 Value:0x000000000000020f Counter:001 Value:0x00000000000001d8
   Counter:002 Value:0x000000000000d7fa Counter:003 Value:0x000000000000008b
   ...

The number in brackets is the offset into the raw data field of the
sample.

New functions trace_event_sample_raw__init() and s390_sample_raw() are
introduced in the code path to enable interpretation on non s390
platforms. This event bc000 attached raw data is generated only on s390
platform. Correct display on other platforms requires correct endianness
handling.

Committer notes:

Added a init function that sets up a evlist function pointer to avoid
repeated tests on evlist->env and calls to perf_env__name() that
involves normalizing, etc, for each PERF_RECORD_SAMPLE.

Removed needless __maybe_unused from the trace_event_raw()
prototype in session.h, move it to be an static function in evlist.

The 'offset' variable is a size_t, not an u64, fix it to avoid this on
some arches:

    CC       /tmp/build/perf/util/s390-sample-raw.o
  util/s390-sample-raw.c: In function 's390_cpumcfdg_testctr':
  util/s390-sample-raw.c:77:4: error: format '%llx' expects argument of type 'long long unsigned int', but argument 4 has type 'size_t' [-Werror=format=]
      pr_err("Invalid counter set entry at %#"  PRIx64 "\n",
      ^
  cc1: all warnings being treated as errors

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Link: https://lkml.kernel.org/r/9c856ac0-ef23-72b5-901d-a1f815508976@linux.ibm.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Link: https://lkml.kernel.org/n/tip-s3jhif06et9ug78qhclw41z1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/tools/perf/util/sample-raw.c b/tools/perf/util/sample-raw.c
new file mode 100644
index 000000000000..c21e1311fb0f
--- /dev/null
+++ b/tools/perf/util/sample-raw.c
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <string.h>
+#include "evlist.h"
+#include "env.h"
+#include "sample-raw.h"
+
+/*
+ * Check platform the perf data file was created on and perform platform
+ * specific interpretation.
+ */
+void perf_evlist__init_trace_event_sample_raw(struct perf_evlist *evlist)
+{
+	const char *arch_pf = perf_env__arch(evlist->env);
+
+	if (arch_pf && !strcmp("s390", arch_pf))
+		evlist->trace_event_sample_raw = perf_evlist__s390_sample_raw;
+}