perf test: Add user space counter reading tests

These tests are based on test_stat_user_read in
tools/lib/perf/tests/test-evsel.c.

The tests are modified to skip if perf_event_open fails or rdpmc isn't
supported.

Committer testing:

  ⬢[acme@toolbox perf]$ perf test "mmap interface"
    4: mmap interface tests                         :
    4.1: Read samples using the mmap interface      : Skip (permissions)
  ⬢[acme@toolbox perf]$

  [root@five ~]# perf test "mmap interface"
    4: mmap interface tests                         :
    4.1: Read samples using the mmap interface      : Ok
  [root@five ~]#

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20220719223946.176299-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/tests/mmap-basic.c b/tools/perf/tests/mmap-basic.c
index 30bbe14..dfb6173 100644 (file)
--- a/tools/perf/tests/mmap-basic.c
+++ b/tools/perf/tests/mmap-basic.c
@@ -170,14 +170,139 @@ out_free_threads:
        return err;
 }
 
+static int test_stat_user_read(int event)
+{
+       struct perf_counts_values counts = { .val = 0 };
+       struct perf_thread_map *threads;
+       struct perf_evsel *evsel;
+       struct perf_event_mmap_page *pc;
+       struct perf_event_attr attr = {
+               .type   = PERF_TYPE_HARDWARE,
+               .config = event,
+#ifdef __aarch64__
+               .config1 = 0x2,         /* Request user access */
+#endif
+       };
+       int err, i, ret = TEST_FAIL;
+       bool opened = false, mapped = false;
+
+       threads = perf_thread_map__new_dummy();
+       TEST_ASSERT_VAL("failed to create threads", threads);
+
+       perf_thread_map__set_pid(threads, 0, 0);
+
+       evsel = perf_evsel__new(&attr);
+       TEST_ASSERT_VAL("failed to create evsel", evsel);
+
+       err = perf_evsel__open(evsel, NULL, threads);
+       if (err) {
+               pr_err("failed to open evsel: %s\n", strerror(-err));
+               ret = TEST_SKIP;
+               goto out;
+       }
+       opened = true;
+
+       err = perf_evsel__mmap(evsel, 0);
+       if (err) {
+               pr_err("failed to mmap evsel: %s\n", strerror(-err));
+               goto out;
+       }
+       mapped = true;
+
+       pc = perf_evsel__mmap_base(evsel, 0, 0);
+       if (!pc) {
+               pr_err("failed to get mmapped address\n");
+               goto out;
+       }
+
+       if (!pc->cap_user_rdpmc || !pc->index) {
+               pr_err("userspace counter access not %s\n",
+                       !pc->cap_user_rdpmc ? "supported" : "enabled");
+               ret = TEST_SKIP;
+               goto out;
+       }
+       if (pc->pmc_width < 32) {
+               pr_err("userspace counter width not set (%d)\n", pc->pmc_width);
+               goto out;
+       }
+
+       perf_evsel__read(evsel, 0, 0, &counts);
+       if (counts.val == 0) {
+               pr_err("failed to read value for evsel\n");
+               goto out;
+       }
+
+       for (i = 0; i < 5; i++) {
+               volatile int count = 0x10000 << i;
+               __u64 start, end, last = 0;
+
+               pr_debug("\tloop = %u, ", count);
+
+               perf_evsel__read(evsel, 0, 0, &counts);
+               start = counts.val;
+
+               while (count--) ;
+
+               perf_evsel__read(evsel, 0, 0, &counts);
+               end = counts.val;
+
+               if ((end - start) < last) {
+                       pr_err("invalid counter data: end=%llu start=%llu last= %llu\n",
+                               end, start, last);
+                       goto out;
+               }
+               last = end - start;
+               pr_debug("count = %llu\n", end - start);
+       }
+       ret = TEST_OK;
+
+out:
+       if (mapped)
+               perf_evsel__munmap(evsel);
+       if (opened)
+               perf_evsel__close(evsel);
+       perf_evsel__delete(evsel);
+
+       perf_thread_map__put(threads);
+       return ret;
+}
+
+static int test__mmap_user_read_instr(struct test_suite *test __maybe_unused,
+                                     int subtest __maybe_unused)
+{
+       return test_stat_user_read(PERF_COUNT_HW_INSTRUCTIONS);
+}
+
+static int test__mmap_user_read_cycles(struct test_suite *test __maybe_unused,
+                                      int subtest __maybe_unused)
+{
+       return test_stat_user_read(PERF_COUNT_HW_CPU_CYCLES);
+}
+
 static struct test_case tests__basic_mmap[] = {
        TEST_CASE_REASON("Read samples using the mmap interface",
                         basic_mmap,
                         "permissions"),
+       TEST_CASE_REASON("User space counter reading of instructions",
+                        mmap_user_read_instr,
+#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
+                        "permissions"
+#else
+                        "unsupported"
+#endif
+               ),
+       TEST_CASE_REASON("User space counter reading of cycles",
+                        mmap_user_read_cycles,
+#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
+                        "permissions"
+#else
+                        "unsupported"
+#endif
+               ),
        {       .name = NULL, }
 };
 
 struct test_suite suite__basic_mmap = {
-       .desc = "Read samples using the mmap interface",
+       .desc = "mmap interface tests",
        .test_cases = tests__basic_mmap,
 };