kvm-stat.c

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// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include "../../util/kvm-stat.h"
#include <asm/svm.h>
#include <asm/vmx.h>
#include <asm/kvm.h>

define_exit_reasons_table(vmx_exit_reasons, VMX_EXIT_REASONS);
define_exit_reasons_table(svm_exit_reasons, SVM_EXIT_REASONS);

static struct kvm_events_ops exit_events = {
    .is_begin_event = exit_event_begin,
    .is_end_event = exit_event_end,
    .decode_key = exit_event_decode_key,
    .name = "VM-EXIT"
};

const char *vcpu_id_str = "vcpu_id";
const int decode_str_len = 20;
const char *kvm_exit_reason = "exit_reason";
const char *kvm_entry_trace = "kvm:kvm_entry";
const char *kvm_exit_trace = "kvm:kvm_exit";

/*
 * For the mmio events, we treat:
 * the time of MMIO write: kvm_mmio(KVM_TRACE_MMIO_WRITE...) -> kvm_entry
 * the time of MMIO read: kvm_exit -> kvm_mmio(KVM_TRACE_MMIO_READ...).
 */
static void mmio_event_get_key(struct perf_evsel *evsel, struct perf_sample *sample,
                   struct event_key *key)
{
    key->key  = perf_evsel__intval(evsel, sample, "gpa");
    key->info = perf_evsel__intval(evsel, sample, "type");
}

#define KVM_TRACE_MMIO_READ_UNSATISFIED 0
#define KVM_TRACE_MMIO_READ 1
#define KVM_TRACE_MMIO_WRITE 2

static bool mmio_event_begin(struct perf_evsel *evsel,
                 struct perf_sample *sample, struct event_key *key)
{
    /* MMIO read begin event in kernel. */
    if (kvm_exit_event(evsel))
        return true;

    /* MMIO write begin event in kernel. */
    if (!strcmp(evsel->name, "kvm:kvm_mmio") &&
        perf_evsel__intval(evsel, sample, "type") == KVM_TRACE_MMIO_WRITE) {
        mmio_event_get_key(evsel, sample, key);
        return true;
    }

    return false;
}

static bool mmio_event_end(struct perf_evsel *evsel, struct perf_sample *sample,
               struct event_key *key)
{
    /* MMIO write end event in kernel. */
    if (kvm_entry_event(evsel))
        return true;

    /* MMIO read end event in kernel.*/
    if (!strcmp(evsel->name, "kvm:kvm_mmio") &&
        perf_evsel__intval(evsel, sample, "type") == KVM_TRACE_MMIO_READ) {
        mmio_event_get_key(evsel, sample, key);
        return true;
    }

    return false;
}

static void mmio_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
                  struct event_key *key,
                  char *decode)
{
    scnprintf(decode, decode_str_len, "%#lx:%s",
          (unsigned long)key->key,
          key->info == KVM_TRACE_MMIO_WRITE ? "W" : "R");
}

static struct kvm_events_ops mmio_events = {
    .is_begin_event = mmio_event_begin,
    .is_end_event = mmio_event_end,
    .decode_key = mmio_event_decode_key,
    .name = "MMIO Access"
};

 /* The time of emulation pio access is from kvm_pio to kvm_entry. */
static void ioport_event_get_key(struct perf_evsel *evsel,
                 struct perf_sample *sample,
                 struct event_key *key)
{
    key->key  = perf_evsel__intval(evsel, sample, "port");
    key->info = perf_evsel__intval(evsel, sample, "rw");
}

static bool ioport_event_begin(struct perf_evsel *evsel,
                   struct perf_sample *sample,
                   struct event_key *key)
{
    if (!strcmp(evsel->name, "kvm:kvm_pio")) {
        ioport_event_get_key(evsel, sample, key);
        return true;
    }

    return false;
}

static bool ioport_event_end(struct perf_evsel *evsel,
                 struct perf_sample *sample __maybe_unused,
                 struct event_key *key __maybe_unused)
{
    return kvm_entry_event(evsel);
}

static void ioport_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
                    struct event_key *key,
                    char *decode)
{
    scnprintf(decode, decode_str_len, "%#llx:%s",
          (unsigned long long)key->key,
          key->info ? "POUT" : "PIN");
}

static struct kvm_events_ops ioport_events = {
    .is_begin_event = ioport_event_begin,
    .is_end_event = ioport_event_end,
    .decode_key = ioport_event_decode_key,
    .name = "IO Port Access"
};

const char *kvm_events_tp[] = {
    "kvm:kvm_entry",
    "kvm:kvm_exit",
    "kvm:kvm_mmio",
    "kvm:kvm_pio",
    NULL,
};

struct kvm_reg_events_ops kvm_reg_events_ops[] = {
    { .name = "vmexit", .ops = &exit_events },
    { .name = "mmio", .ops = &mmio_events },
    { .name = "ioport", .ops = &ioport_events },
    { NULL, NULL },
};

const char * const kvm_skip_events[] = {
    "HLT",
    NULL,
};

int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid)
{
    if (strstr(cpuid, "Intel")) {
        kvm->exit_reasons = vmx_exit_reasons;
        kvm->exit_reasons_isa = "VMX";
    } else if (strstr(cpuid, "AMD")) {
        kvm->exit_reasons = svm_exit_reasons;
        kvm->exit_reasons_isa = "SVM";
    } else
        return -ENOTSUP;

    return 0;
}