perf report: Dump s390 counter set data to file

Add support for the new s390 PMU device cpum_cf_diag to extract the
counter set diagnostic data. This data is available as event raw data
and can be created with this command:

  [root@s35lp76 perf]# ./perf record -R -e '{rbd000,rbc000}' --
                                 ~/mytests/facultaet 2500
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.009 MB perf.data ]
  [root@s35lp76 perf]#

The new event 0xbc000 generated this counter set diagnostic trace data.
The data can be extracted using command:

  [root@s35lp76 perf]# ./perf report --stdio --itrace=d
  #
  # Total Lost Samples: 0
  #
  # Samples: 21  of events 'anon group { rbd000, rbc000 }'
  # Event count (approx.): 21
  #
  #         Overhead  Command    Shared Object      Symbol
  # ................  .........  .................  ........................
  #
    80.95%   0.00%  facultaet  facultaet          [.] facultaet
     4.76%   0.00%  facultaet  [kernel.kallsyms]  [k] check_chain_key
     4.76%   0.00%  facultaet  [kernel.kallsyms]  [k] ftrace_likely_update
     4.76%   0.00%  facultaet  [kernel.kallsyms]  [k] lock_release
     4.76%   0.00%  facultaet  libc-2.26.so       [.] _dl_addr
  [root@s35lp76 perf]# ll aux*
  -rw-r--r-- 1 root root 3408 Oct 16 12:40 aux.ctr.02
  -rw-r--r-- 1 root root 4096 Oct 16 12:40 aux.smp.02
  [root@s35lp76 perf]#

The files named aux.ctr.## contain the counter set diagnostic data and
the files named aux.smp.## contain the sampling diagnostic data. ##
stand for the CPU number the data was taken from.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20190117093003.96287-4-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/s390-cpumsf.c b/tools/perf/util/s390-cpumsf.c
index 68b2570304eceb5499b471d1a5f350aaac115800..835249c77f568df7a738a8437b88d225dd7dedb8 100644 (file)
--- a/tools/perf/util/s390-cpumsf.c
+++ b/tools/perf/util/s390-cpumsf.c
@@ -162,6 +162,7 @@
 #include "auxtrace.h"
 #include "s390-cpumsf.h"
 #include "s390-cpumsf-kernel.h"
+#include "s390-cpumcf-kernel.h"
 #include "config.h"
 
 struct s390_cpumsf {
@@ -184,8 +185,58 @@ struct s390_cpumsf_queue {
        struct auxtrace_buffer  *buffer;
        int                     cpu;
        FILE                    *logfile;
+       FILE                    *logfile_ctr;
 };
 
+/* Check if the raw data should be dumped to file. If this is the case and
+ * the file to dump to has not been opened for writing, do so.
+ *
+ * Return 0 on success and greater zero on error so processing continues.
+ */
+static int s390_cpumcf_dumpctr(struct s390_cpumsf *sf,
+                              struct perf_sample *sample)
+{
+       struct s390_cpumsf_queue *sfq;
+       struct auxtrace_queue *q;
+       int rc = 0;
+
+       if (!sf->use_logfile || sf->queues.nr_queues <= sample->cpu)
+               return rc;
+
+       q = &sf->queues.queue_array[sample->cpu];
+       sfq = q->priv;
+       if (!sfq)               /* Queue not yet allocated */
+               return rc;
+
+       if (!sfq->logfile_ctr) {
+               char *name;
+
+               rc = (sf->logdir)
+                       ? asprintf(&name, "%s/aux.ctr.%02x",
+                                sf->logdir, sample->cpu)
+                       : asprintf(&name, "aux.ctr.%02x", sample->cpu);
+               if (rc > 0)
+                       sfq->logfile_ctr = fopen(name, "w");
+               if (sfq->logfile_ctr == NULL) {
+                       pr_err("Failed to open counter set log file %s, "
+                              "continue...\n", name);
+                       rc = 1;
+               }
+               free(name);
+       }
+
+       if (sfq->logfile_ctr) {
+               /* See comment above for -4 */
+               size_t n = fwrite(sample->raw_data, sample->raw_size - 4, 1,
+                                 sfq->logfile_ctr);
+               if (n != 1) {
+                       pr_err("Failed to write counter set data\n");
+                       rc = 1;
+               }
+       }
+       return rc;
+}
+
 /* Display s390 CPU measurement facility basic-sampling data entry */
 static bool s390_cpumsf_basic_show(const char *color, size_t pos,
                                   struct hws_basic_entry *basic)
@@ -792,7 +843,7 @@ static int s390_cpumsf_lost(struct s390_cpumsf *sf, struct perf_sample *sample)
 }
 
 static int
-s390_cpumsf_process_event(struct perf_session *session __maybe_unused,
+s390_cpumsf_process_event(struct perf_session *session,
                          union perf_event *event,
                          struct perf_sample *sample,
                          struct perf_tool *tool)
@@ -801,6 +852,8 @@ s390_cpumsf_process_event(struct perf_session *session __maybe_unused,
                                              struct s390_cpumsf,
                                              auxtrace);
        u64 timestamp = sample->time;
+       struct perf_evsel *ev_bc000;
+
        int err = 0;
 
        if (dump_trace)
@@ -811,6 +864,16 @@ s390_cpumsf_process_event(struct perf_session *session __maybe_unused,
                return -EINVAL;
        }
 
+       if (event->header.type == PERF_RECORD_SAMPLE &&
+           sample->raw_size) {
+               /* Handle event with raw data */
+               ev_bc000 = perf_evlist__event2evsel(session->evlist, event);
+               if (ev_bc000 &&
+                   ev_bc000->attr.config == PERF_EVENT_CPUM_CF_DIAG)
+                       err = s390_cpumcf_dumpctr(sf, sample);
+               return err;
+       }
+
        if (event->header.type == PERF_RECORD_AUX &&
            event->aux.flags & PERF_AUX_FLAG_TRUNCATED)
                return s390_cpumsf_lost(sf, sample);
@@ -891,9 +954,15 @@ static void s390_cpumsf_free_queues(struct perf_session *session)
                struct s390_cpumsf_queue *sfq = (struct s390_cpumsf_queue *)
                                                queues->queue_array[i].priv;
 
-               if (sfq != NULL && sfq->logfile) {
-                       fclose(sfq->logfile);
-                       sfq->logfile = NULL;
+               if (sfq != NULL) {
+                       if (sfq->logfile) {
+                               fclose(sfq->logfile);
+                               sfq->logfile = NULL;
+                       }
+                       if (sfq->logfile_ctr) {
+                               fclose(sfq->logfile_ctr);
+                               sfq->logfile_ctr = NULL;
+                       }
                }
                zfree(&queues->queue_array[i].priv);
        }