perf kvm: Add kvm-stat for arm64

Add support for 'perf kvm stat' on arm64 platform.

Example:

  # perf kvm stat report

Analyze events for all VMs, all VCPUs:

    VM-EXIT    Samples  Samples%     Time%    Min Time    Max Time         Avg time

   DABT_LOW     661867    98.91%    40.45%      2.19us   3364.65us      6.24us ( +-   0.34% )
        IRQ       4598     0.69%    57.44%      2.89us   3397.59us   1276.27us ( +-   1.61% )
        WFx       1475     0.22%     1.71%      2.22us   3388.63us    118.31us ( +-   8.69% )
   IABT_LOW       1018     0.15%     0.38%      2.22us   2742.07us     38.29us ( +-  12.55% )
      SYS64        180     0.03%     0.01%      2.07us    112.91us      6.57us ( +-  14.95% )
      HVC64         17     0.00%     0.01%      2.19us    322.35us     42.95us ( +-  58.98% )

Total Samples:669155, Total events handled time:10216387.86us.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Suleiman Souhlal <suleiman@google.com>
Link: http://lore.kernel.org/lkml/20201027062421.463355-1-sergey.senozhatsky@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/tools/perf/arch/arm64/util/kvm-stat.c b/tools/perf/arch/arm64/util/kvm-stat.c
new file mode 100644
index 000000000000..50376b9062c1
--- /dev/null
+++ b/tools/perf/arch/arm64/util/kvm-stat.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <errno.h>
+#include <memory.h>
+#include "../../util/evsel.h"
+#include "../../util/kvm-stat.h"
+#include "arm64_exception_types.h"
+#include "debug.h"
+
+define_exit_reasons_table(arm64_exit_reasons, kvm_arm_exception_type);
+define_exit_reasons_table(arm64_trap_exit_reasons, kvm_arm_exception_class);
+
+const char *kvm_trap_exit_reason = "esr_ec";
+const char *vcpu_id_str = "id";
+const int decode_str_len = 20;
+const char *kvm_exit_reason = "ret";
+const char *kvm_entry_trace = "kvm:kvm_entry";
+const char *kvm_exit_trace = "kvm:kvm_exit";
+
+const char *kvm_events_tp[] = {
+	"kvm:kvm_entry",
+	"kvm:kvm_exit",
+	NULL,
+};
+
+static void event_get_key(struct evsel *evsel,
+			  struct perf_sample *sample,
+			  struct event_key *key)
+{
+	key->info = 0;
+	key->key = evsel__intval(evsel, sample, kvm_exit_reason);
+	key->exit_reasons = arm64_exit_reasons;
+
+	/*
+	 * TRAP exceptions carry exception class info in esr_ec field
+	 * and, hence, we need to use a different exit_reasons table to
+	 * properly decode event's est_ec.
+	 */
+	if (key->key == ARM_EXCEPTION_TRAP) {
+		key->key = evsel__intval(evsel, sample, kvm_trap_exit_reason);
+		key->exit_reasons = arm64_trap_exit_reasons;
+	}
+}
+
+static bool event_begin(struct evsel *evsel,
+			struct perf_sample *sample __maybe_unused,
+			struct event_key *key __maybe_unused)
+{
+	return !strcmp(evsel->name, kvm_entry_trace);
+}
+
+static bool event_end(struct evsel *evsel,
+		      struct perf_sample *sample,
+		      struct event_key *key)
+{
+	if (!strcmp(evsel->name, kvm_exit_trace)) {
+		event_get_key(evsel, sample, key);
+		return true;
+	}
+	return false;
+}
+
+static struct kvm_events_ops exit_events = {
+	.is_begin_event = event_begin,
+	.is_end_event	= event_end,
+	.decode_key	= exit_event_decode_key,
+	.name		= "VM-EXIT"
+};
+
+struct kvm_reg_events_ops kvm_reg_events_ops[] = {
+	{
+		.name	= "vmexit",
+		.ops	= &exit_events,
+	},
+	{ NULL },
+};
+
+const char * const kvm_skip_events[] = {
+	NULL,
+};
+
+int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid __maybe_unused)
+{
+	kvm->exit_reasons_isa = "arm64";
+	return 0;
+}