stat-shadow.c

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// SPDX-License-Identifier: GPL-2.0
#include <stdio.h>
#include "evsel.h"
#include "stat.h"
#include "color.h"
#include "pmu.h"
#include "rblist.h"
#include "evlist.h"
#include "expr.h"
#include "metricgroup.h"

/*
 * AGGR_GLOBAL: Use CPU 0
 * AGGR_SOCKET: Use first CPU of socket
 * AGGR_CORE: Use first CPU of core
 * AGGR_NONE: Use matching CPU
 * AGGR_THREAD: Not supported?
 */
static bool have_frontend_stalled;

struct runtime_stat rt_stat;
struct stats walltime_nsecs_stats;

struct saved_value {
    struct rb_node rb_node;
    struct perf_evsel *evsel;
    enum stat_type type;
    int ctx;
    int cpu;
    struct runtime_stat *stat;
    struct stats stats;
};

static int saved_value_cmp(struct rb_node *rb_node, const void *entry)
{
    struct saved_value *a = container_of(rb_node,
                         struct saved_value,
                         rb_node);
    const struct saved_value *b = entry;

    if (a->cpu != b->cpu)
        return a->cpu - b->cpu;

    /*
     * Previously the rbtree was used to link generic metrics.
     * The keys were evsel/cpu. Now the rbtree is extended to support
     * per-thread shadow stats. For shadow stats case, the keys
     * are cpu/type/ctx/stat (evsel is NULL). For generic metrics
     * case, the keys are still evsel/cpu (type/ctx/stat are 0 or NULL).
     */
    if (a->type != b->type)
        return a->type - b->type;

    if (a->ctx != b->ctx)
        return a->ctx - b->ctx;

    if (a->evsel == NULL && b->evsel == NULL) {
        if (a->stat == b->stat)
            return 0;

        if ((char *)a->stat < (char *)b->stat)
            return -1;

        return 1;
    }

    if (a->evsel == b->evsel)
        return 0;
    if ((char *)a->evsel < (char *)b->evsel)
        return -1;
    return +1;
}

static struct rb_node *saved_value_new(struct rblist *rblist __maybe_unused,
                     const void *entry)
{
    struct saved_value *nd = malloc(sizeof(struct saved_value));

    if (!nd)
        return NULL;
    memcpy(nd, entry, sizeof(struct saved_value));
    return &nd->rb_node;
}

static void saved_value_delete(struct rblist *rblist __maybe_unused,
                   struct rb_node *rb_node)
{
    struct saved_value *v;

    BUG_ON(!rb_node);
    v = container_of(rb_node, struct saved_value, rb_node);
    free(v);
}

static struct saved_value *saved_value_lookup(struct perf_evsel *evsel,
                          int cpu,
                          bool create,
                          enum stat_type type,
                          int ctx,
                          struct runtime_stat *st)
{
    struct rblist *rblist;
    struct rb_node *nd;
    struct saved_value dm = {
        .cpu = cpu,
        .evsel = evsel,
        .type = type,
        .ctx = ctx,
        .stat = st,
    };

    rblist = &st->value_list;

    nd = rblist__find(rblist, &dm);
    if (nd)
        return container_of(nd, struct saved_value, rb_node);
    if (create) {
        rblist__add_node(rblist, &dm);
        nd = rblist__find(rblist, &dm);
        if (nd)
            return container_of(nd, struct saved_value, rb_node);
    }
    return NULL;
}

void runtime_stat__init(struct runtime_stat *st)
{
    struct rblist *rblist = &st->value_list;

    rblist__init(rblist);
    rblist->node_cmp = saved_value_cmp;
    rblist->node_new = saved_value_new;
    rblist->node_delete = saved_value_delete;
}

void runtime_stat__exit(struct runtime_stat *st)
{
    rblist__exit(&st->value_list);
}

void perf_stat__init_shadow_stats(void)
{
    have_frontend_stalled = pmu_have_event("cpu", "stalled-cycles-frontend");
    runtime_stat__init(&rt_stat);
}

static int evsel_context(struct perf_evsel *evsel)
{
    int ctx = 0;

    if (evsel->attr.exclude_kernel)
        ctx |= CTX_BIT_KERNEL;
    if (evsel->attr.exclude_user)
        ctx |= CTX_BIT_USER;
    if (evsel->attr.exclude_hv)
        ctx |= CTX_BIT_HV;
    if (evsel->attr.exclude_host)
        ctx |= CTX_BIT_HOST;
    if (evsel->attr.exclude_idle)
        ctx |= CTX_BIT_IDLE;

    return ctx;
}

static void reset_stat(struct runtime_stat *st)
{
    struct rblist *rblist;
    struct rb_node *pos, *next;

    rblist = &st->value_list;
    next = rb_first(&rblist->entries);
    while (next) {
        pos = next;
        next = rb_next(pos);
        memset(&container_of(pos, struct saved_value, rb_node)->stats,
               0,
               sizeof(struct stats));
    }
}

void perf_stat__reset_shadow_stats(void)
{
    reset_stat(&rt_stat);
    memset(&walltime_nsecs_stats, 0, sizeof(walltime_nsecs_stats));
}

void perf_stat__reset_shadow_per_stat(struct runtime_stat *st)
{
    reset_stat(st);
}

static void update_runtime_stat(struct runtime_stat *st,
                enum stat_type type,
                int ctx, int cpu, u64 count)
{
    struct saved_value *v = saved_value_lookup(NULL, cpu, true,
                           type, ctx, st);

    if (v)
        update_stats(&v->stats, count);
}

/*
 * Update various tracking values we maintain to print
 * more semantic information such as miss/hit ratios,
 * instruction rates, etc:
 */
void perf_stat__update_shadow_stats(struct perf_evsel *counter, u64 count,
                    int cpu, struct runtime_stat *st)
{
    int ctx = evsel_context(counter);

    count *= counter->scale;

    if (perf_evsel__match(counter, SOFTWARE, SW_TASK_CLOCK) ||
        perf_evsel__match(counter, SOFTWARE, SW_CPU_CLOCK))
        update_runtime_stat(st, STAT_NSECS, 0, cpu, count);
    else if (perf_evsel__match(counter, HARDWARE, HW_CPU_CYCLES))
        update_runtime_stat(st, STAT_CYCLES, ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, CYCLES_IN_TX))
        update_runtime_stat(st, STAT_CYCLES_IN_TX, ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, TRANSACTION_START))
        update_runtime_stat(st, STAT_TRANSACTION, ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, ELISION_START))
        update_runtime_stat(st, STAT_ELISION, ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, TOPDOWN_TOTAL_SLOTS))
        update_runtime_stat(st, STAT_TOPDOWN_TOTAL_SLOTS,
                    ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, TOPDOWN_SLOTS_ISSUED))
        update_runtime_stat(st, STAT_TOPDOWN_SLOTS_ISSUED,
                    ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, TOPDOWN_SLOTS_RETIRED))
        update_runtime_stat(st, STAT_TOPDOWN_SLOTS_RETIRED,
                    ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, TOPDOWN_FETCH_BUBBLES))
        update_runtime_stat(st, STAT_TOPDOWN_FETCH_BUBBLES,
                    ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, TOPDOWN_RECOVERY_BUBBLES))
        update_runtime_stat(st, STAT_TOPDOWN_RECOVERY_BUBBLES,
                    ctx, cpu, count);
    else if (perf_evsel__match(counter, HARDWARE, HW_STALLED_CYCLES_FRONTEND))
        update_runtime_stat(st, STAT_STALLED_CYCLES_FRONT,
                    ctx, cpu, count);
    else if (perf_evsel__match(counter, HARDWARE, HW_STALLED_CYCLES_BACKEND))
        update_runtime_stat(st, STAT_STALLED_CYCLES_BACK,
                    ctx, cpu, count);
    else if (perf_evsel__match(counter, HARDWARE, HW_BRANCH_INSTRUCTIONS))
        update_runtime_stat(st, STAT_BRANCHES, ctx, cpu, count);
    else if (perf_evsel__match(counter, HARDWARE, HW_CACHE_REFERENCES))
        update_runtime_stat(st, STAT_CACHEREFS, ctx, cpu, count);
    else if (perf_evsel__match(counter, HW_CACHE, HW_CACHE_L1D))
        update_runtime_stat(st, STAT_L1_DCACHE, ctx, cpu, count);
    else if (perf_evsel__match(counter, HW_CACHE, HW_CACHE_L1I))
        update_runtime_stat(st, STAT_L1_ICACHE, ctx, cpu, count);
    else if (perf_evsel__match(counter, HW_CACHE, HW_CACHE_LL))
        update_runtime_stat(st, STAT_LL_CACHE, ctx, cpu, count);
    else if (perf_evsel__match(counter, HW_CACHE, HW_CACHE_DTLB))
        update_runtime_stat(st, STAT_DTLB_CACHE, ctx, cpu, count);
    else if (perf_evsel__match(counter, HW_CACHE, HW_CACHE_ITLB))
        update_runtime_stat(st, STAT_ITLB_CACHE, ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, SMI_NUM))
        update_runtime_stat(st, STAT_SMI_NUM, ctx, cpu, count);
    else if (perf_stat_evsel__is(counter, APERF))
        update_runtime_stat(st, STAT_APERF, ctx, cpu, count);

    if (counter->collect_stat) {
        struct saved_value *v = saved_value_lookup(counter, cpu, true,
                               STAT_NONE, 0, st);
        update_stats(&v->stats, count);
    }
}

/* used for get_ratio_color() */
enum grc_type {
    GRC_STALLED_CYCLES_FE,
    GRC_STALLED_CYCLES_BE,
    GRC_CACHE_MISSES,
    GRC_MAX_NR
};

static const char *get_ratio_color(enum grc_type type, double ratio)
{
    static const double grc_table[GRC_MAX_NR][3] = {
        [GRC_STALLED_CYCLES_FE] = { 50.0, 30.0, 10.0 },
        [GRC_STALLED_CYCLES_BE] = { 75.0, 50.0, 20.0 },
        [GRC_CACHE_MISSES]  = { 20.0, 10.0, 5.0 },
    };
    const char *color = PERF_COLOR_NORMAL;

    if (ratio > grc_table[type][0])
        color = PERF_COLOR_RED;
    else if (ratio > grc_table[type][1])
        color = PERF_COLOR_MAGENTA;
    else if (ratio > grc_table[type][2])
        color = PERF_COLOR_YELLOW;

    return color;
}

static struct perf_evsel *perf_stat__find_event(struct perf_evlist *evsel_list,
                        const char *name)
{
    struct perf_evsel *c2;

    evlist__for_each_entry (evsel_list, c2) {
        if (!strcasecmp(c2->name, name))
            return c2;
    }
    return NULL;
}

/* Mark MetricExpr target events and link events using them to them. */
void perf_stat__collect_metric_expr(struct perf_evlist *evsel_list)
{
    struct perf_evsel *counter, *leader, **metric_events, *oc;
    bool found;
    const char **metric_names;
    int i;
    int num_metric_names;

    evlist__for_each_entry(evsel_list, counter) {
        bool invalid = false;

        leader = counter->leader;
        if (!counter->metric_expr)
            continue;
        metric_events = counter->metric_events;
        if (!metric_events) {
            if (expr__find_other(counter->metric_expr, counter->name,
                        &metric_names, &num_metric_names) < 0)
                continue;

            metric_events = calloc(sizeof(struct perf_evsel *),
                           num_metric_names + 1);
            if (!metric_events)
                return;
            counter->metric_events = metric_events;
        }

        for (i = 0; i < num_metric_names; i++) {
            found = false;
            if (leader) {
                /* Search in group */
                for_each_group_member (oc, leader) {
                    if (!strcasecmp(oc->name, metric_names[i])) {
                        found = true;
                        break;
                    }
                }
            }
            if (!found) {
                /* Search ignoring groups */
                oc = perf_stat__find_event(evsel_list, metric_names[i]);
            }
            if (!oc) {
                /* Deduping one is good enough to handle duplicated PMUs. */
                static char *printed;

                /*
                 * Adding events automatically would be difficult, because
                 * it would risk creating groups that are not schedulable.
                 * perf stat doesn't understand all the scheduling constraints
                 * of events. So we ask the user instead to add the missing
                 * events.
                 */
                if (!printed || strcasecmp(printed, metric_names[i])) {
                    fprintf(stderr,
                        "Add %s event to groups to get metric expression for %s\n",
                        metric_names[i],
                        counter->name);
                    printed = strdup(metric_names[i]);
                }
                invalid = true;
                continue;
            }
            metric_events[i] = oc;
            oc->collect_stat = true;
        }
        metric_events[i] = NULL;
        free(metric_names);
        if (invalid) {
            free(metric_events);
            counter->metric_events = NULL;
            counter->metric_expr = NULL;
        }
    }
}

static double runtime_stat_avg(struct runtime_stat *st,
                   enum stat_type type, int ctx, int cpu)
{
    struct saved_value *v;

    v = saved_value_lookup(NULL, cpu, false, type, ctx, st);
    if (!v)
        return 0.0;

    return avg_stats(&v->stats);
}

static double runtime_stat_n(struct runtime_stat *st,
                 enum stat_type type, int ctx, int cpu)
{
    struct saved_value *v;

    v = saved_value_lookup(NULL, cpu, false, type, ctx, st);
    if (!v)
        return 0.0;

    return v->stats.n;
}

static void print_stalled_cycles_frontend(int cpu,
                      struct perf_evsel *evsel, double avg,
                      struct perf_stat_output_ctx *out,
                      struct runtime_stat *st)
{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_CYCLES, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_STALLED_CYCLES_FE, ratio);

    if (ratio)
        out->print_metric(out->ctx, color, "%7.2f%%", "frontend cycles idle",
                  ratio);
    else
        out->print_metric(out->ctx, NULL, NULL, "frontend cycles idle", 0);
}

static void print_stalled_cycles_backend(int cpu,
                     struct perf_evsel *evsel, double avg,
                     struct perf_stat_output_ctx *out,
                     struct runtime_stat *st)
{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_CYCLES, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_STALLED_CYCLES_BE, ratio);

    out->print_metric(out->ctx, color, "%7.2f%%", "backend cycles idle", ratio);
}

static void print_branch_misses(int cpu,
                struct perf_evsel *evsel,
                double avg,
                struct perf_stat_output_ctx *out,
                struct runtime_stat *st)
{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_BRANCHES, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_CACHE_MISSES, ratio);

    out->print_metric(out->ctx, color, "%7.2f%%", "of all branches", ratio);
}

static void print_l1_dcache_misses(int cpu,
                   struct perf_evsel *evsel,
                   double avg,
                   struct perf_stat_output_ctx *out,
                   struct runtime_stat *st)

{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_L1_DCACHE, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_CACHE_MISSES, ratio);

    out->print_metric(out->ctx, color, "%7.2f%%", "of all L1-dcache hits", ratio);
}

static void print_l1_icache_misses(int cpu,
                   struct perf_evsel *evsel,
                   double avg,
                   struct perf_stat_output_ctx *out,
                   struct runtime_stat *st)

{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_L1_ICACHE, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_CACHE_MISSES, ratio);
    out->print_metric(out->ctx, color, "%7.2f%%", "of all L1-icache hits", ratio);
}

static void print_dtlb_cache_misses(int cpu,
                    struct perf_evsel *evsel,
                    double avg,
                    struct perf_stat_output_ctx *out,
                    struct runtime_stat *st)
{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_DTLB_CACHE, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_CACHE_MISSES, ratio);
    out->print_metric(out->ctx, color, "%7.2f%%", "of all dTLB cache hits", ratio);
}

static void print_itlb_cache_misses(int cpu,
                    struct perf_evsel *evsel,
                    double avg,
                    struct perf_stat_output_ctx *out,
                    struct runtime_stat *st)
{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_ITLB_CACHE, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_CACHE_MISSES, ratio);
    out->print_metric(out->ctx, color, "%7.2f%%", "of all iTLB cache hits", ratio);
}

static void print_ll_cache_misses(int cpu,
                  struct perf_evsel *evsel,
                  double avg,
                  struct perf_stat_output_ctx *out,
                  struct runtime_stat *st)
{
    double total, ratio = 0.0;
    const char *color;
    int ctx = evsel_context(evsel);

    total = runtime_stat_avg(st, STAT_LL_CACHE, ctx, cpu);

    if (total)
        ratio = avg / total * 100.0;

    color = get_ratio_color(GRC_CACHE_MISSES, ratio);
    out->print_metric(out->ctx, color, "%7.2f%%", "of all LL-cache hits", ratio);
}

/*
 * High level "TopDown" CPU core pipe line bottleneck break down.
 *
 * Basic concept following
 * Yasin, A Top Down Method for Performance analysis and Counter architecture
 * ISPASS14
 *
 * The CPU pipeline is divided into 4 areas that can be bottlenecks:
 *
 * Frontend -> Backend -> Retiring
 * BadSpeculation in addition means out of order execution that is thrown away
 * (for example branch mispredictions)
 * Frontend is instruction decoding.
 * Backend is execution, like computation and accessing data in memory
 * Retiring is good execution that is not directly bottlenecked
 *
 * The formulas are computed in slots.
 * A slot is an entry in the pipeline each for the pipeline width
 * (for example a 4-wide pipeline has 4 slots for each cycle)
 *
 * Formulas:
 * BadSpeculation = ((SlotsIssued - SlotsRetired) + RecoveryBubbles) /
 *          TotalSlots
 * Retiring = SlotsRetired / TotalSlots
 * FrontendBound = FetchBubbles / TotalSlots
 * BackendBound = 1.0 - BadSpeculation - Retiring - FrontendBound
 *
 * The kernel provides the mapping to the low level CPU events and any scaling
 * needed for the CPU pipeline width, for example:
 *
 * TotalSlots = Cycles * 4
 *
 * The scaling factor is communicated in the sysfs unit.
 *
 * In some cases the CPU may not be able to measure all the formulas due to
 * missing events. In this case multiple formulas are combined, as possible.
 *
 * Full TopDown supports more levels to sub-divide each area: for example
 * BackendBound into computing bound and memory bound. For now we only
 * support Level 1 TopDown.
 */

static double sanitize_val(double x)
{
    if (x < 0 && x >= -0.02)
        return 0.0;
    return x;
}

static double td_total_slots(int ctx, int cpu, struct runtime_stat *st)
{
    return runtime_stat_avg(st, STAT_TOPDOWN_TOTAL_SLOTS, ctx, cpu);
}

static double td_bad_spec(int ctx, int cpu, struct runtime_stat *st)
{
    double bad_spec = 0;
    double total_slots;
    double total;

    total = runtime_stat_avg(st, STAT_TOPDOWN_SLOTS_ISSUED, ctx, cpu) -
        runtime_stat_avg(st, STAT_TOPDOWN_SLOTS_RETIRED, ctx, cpu) +
        runtime_stat_avg(st, STAT_TOPDOWN_RECOVERY_BUBBLES, ctx, cpu);

    total_slots = td_total_slots(ctx, cpu, st);
    if (total_slots)
        bad_spec = total / total_slots;
    return sanitize_val(bad_spec);
}

static double td_retiring(int ctx, int cpu, struct runtime_stat *st)
{
    double retiring = 0;
    double total_slots = td_total_slots(ctx, cpu, st);
    double ret_slots = runtime_stat_avg(st, STAT_TOPDOWN_SLOTS_RETIRED,
                        ctx, cpu);

    if (total_slots)
        retiring = ret_slots / total_slots;
    return retiring;
}

static double td_fe_bound(int ctx, int cpu, struct runtime_stat *st)
{
    double fe_bound = 0;
    double total_slots = td_total_slots(ctx, cpu, st);
    double fetch_bub = runtime_stat_avg(st, STAT_TOPDOWN_FETCH_BUBBLES,
                        ctx, cpu);

    if (total_slots)
        fe_bound = fetch_bub / total_slots;
    return fe_bound;
}

static double td_be_bound(int ctx, int cpu, struct runtime_stat *st)
{
    double sum = (td_fe_bound(ctx, cpu, st) +
              td_bad_spec(ctx, cpu, st) +
              td_retiring(ctx, cpu, st));
    if (sum == 0)
        return 0;
    return sanitize_val(1.0 - sum);
}

static void print_smi_cost(int cpu, struct perf_evsel *evsel,
               struct perf_stat_output_ctx *out,
               struct runtime_stat *st)
{
    double smi_num, aperf, cycles, cost = 0.0;
    int ctx = evsel_context(evsel);
    const char *color = NULL;

    smi_num = runtime_stat_avg(st, STAT_SMI_NUM, ctx, cpu);
    aperf = runtime_stat_avg(st, STAT_APERF, ctx, cpu);
    cycles = runtime_stat_avg(st, STAT_CYCLES, ctx, cpu);

    if ((cycles == 0) || (aperf == 0))
        return;

    if (smi_num)
        cost = (aperf - cycles) / aperf * 100.00;

    if (cost > 10)
        color = PERF_COLOR_RED;
    out->print_metric(out->ctx, color, "%8.1f%%", "SMI cycles%", cost);
    out->print_metric(out->ctx, NULL, "%4.0f", "SMI#", smi_num);
}

static void generic_metric(const char *metric_expr,
               struct perf_evsel **metric_events,
               char *name,
               const char *metric_name,
               double avg,
               int cpu,
               struct perf_stat_output_ctx *out,
               struct runtime_stat *st)
{
    print_metric_t print_metric = out->print_metric;
    struct parse_ctx pctx;
    double ratio;
    int i;
    void *ctxp = out->ctx;

    expr__ctx_init(&pctx);
    expr__add_id(&pctx, name, avg);
    for (i = 0; metric_events[i]; i++) {
        struct saved_value *v;
        struct stats *stats;
        double scale;

        if (!strcmp(metric_events[i]->name, "duration_time")) {
            stats = &walltime_nsecs_stats;
            scale = 1e-9;
        } else {
            v = saved_value_lookup(metric_events[i], cpu, false,
                           STAT_NONE, 0, st);
            if (!v)
                break;
            stats = &v->stats;
            scale = 1.0;
        }
        expr__add_id(&pctx, metric_events[i]->name, avg_stats(stats)*scale);
    }
    if (!metric_events[i]) {
        const char *p = metric_expr;

        if (expr__parse(&ratio, &pctx, &p) == 0)
            print_metric(ctxp, NULL, "%8.1f",
                metric_name ?
                metric_name :
                out->force_header ?  name : "",
                ratio);
        else
            print_metric(ctxp, NULL, NULL,
                     out->force_header ?
                     (metric_name ? metric_name : name) : "", 0);
    } else
        print_metric(ctxp, NULL, NULL, "", 0);
}

void perf_stat__print_shadow_stats(struct perf_evsel *evsel,
                   double avg, int cpu,
                   struct perf_stat_output_ctx *out,
                   struct rblist *metric_events,
                   struct runtime_stat *st)
{
    void *ctxp = out->ctx;
    print_metric_t print_metric = out->print_metric;
    double total, ratio = 0.0, total2;
    const char *color = NULL;
    int ctx = evsel_context(evsel);
    struct metric_event *me;
    int num = 1;

    if (perf_evsel__match(evsel, HARDWARE, HW_INSTRUCTIONS)) {
        total = runtime_stat_avg(st, STAT_CYCLES, ctx, cpu);

        if (total) {
            ratio = avg / total;
            print_metric(ctxp, NULL, "%7.2f ",
                    "insn per cycle", ratio);
        } else {
            print_metric(ctxp, NULL, NULL, "insn per cycle", 0);
        }

        total = runtime_stat_avg(st, STAT_STALLED_CYCLES_FRONT,
                     ctx, cpu);

        total = max(total, runtime_stat_avg(st,
                            STAT_STALLED_CYCLES_BACK,
                            ctx, cpu));

        if (total && avg) {
            out->new_line(ctxp);
            ratio = total / avg;
            print_metric(ctxp, NULL, "%7.2f ",
                    "stalled cycles per insn",
                    ratio);
        } else if (have_frontend_stalled) {
            print_metric(ctxp, NULL, NULL,
                     "stalled cycles per insn", 0);
        }
    } else if (perf_evsel__match(evsel, HARDWARE, HW_BRANCH_MISSES)) {
        if (runtime_stat_n(st, STAT_BRANCHES, ctx, cpu) != 0)
            print_branch_misses(cpu, evsel, avg, out, st);
        else
            print_metric(ctxp, NULL, NULL, "of all branches", 0);
    } else if (
        evsel->attr.type == PERF_TYPE_HW_CACHE &&
        evsel->attr.config ==  ( PERF_COUNT_HW_CACHE_L1D |
                    ((PERF_COUNT_HW_CACHE_OP_READ) << 8) |
                     ((PERF_COUNT_HW_CACHE_RESULT_MISS) << 16))) {

        if (runtime_stat_n(st, STAT_L1_DCACHE, ctx, cpu) != 0)
            print_l1_dcache_misses(cpu, evsel, avg, out, st);
        else
            print_metric(ctxp, NULL, NULL, "of all L1-dcache hits", 0);
    } else if (
        evsel->attr.type == PERF_TYPE_HW_CACHE &&
        evsel->attr.config ==  ( PERF_COUNT_HW_CACHE_L1I |
                    ((PERF_COUNT_HW_CACHE_OP_READ) << 8) |
                     ((PERF_COUNT_HW_CACHE_RESULT_MISS) << 16))) {

        if (runtime_stat_n(st, STAT_L1_ICACHE, ctx, cpu) != 0)
            print_l1_icache_misses(cpu, evsel, avg, out, st);
        else
            print_metric(ctxp, NULL, NULL, "of all L1-icache hits", 0);
    } else if (
        evsel->attr.type == PERF_TYPE_HW_CACHE &&
        evsel->attr.config ==  ( PERF_COUNT_HW_CACHE_DTLB |
                    ((PERF_COUNT_HW_CACHE_OP_READ) << 8) |
                     ((PERF_COUNT_HW_CACHE_RESULT_MISS) << 16))) {

        if (runtime_stat_n(st, STAT_DTLB_CACHE, ctx, cpu) != 0)
            print_dtlb_cache_misses(cpu, evsel, avg, out, st);
        else
            print_metric(ctxp, NULL, NULL, "of all dTLB cache hits", 0);
    } else if (
        evsel->attr.type == PERF_TYPE_HW_CACHE &&
        evsel->attr.config ==  ( PERF_COUNT_HW_CACHE_ITLB |
                    ((PERF_COUNT_HW_CACHE_OP_READ) << 8) |
                     ((PERF_COUNT_HW_CACHE_RESULT_MISS) << 16))) {

        if (runtime_stat_n(st, STAT_ITLB_CACHE, ctx, cpu) != 0)
            print_itlb_cache_misses(cpu, evsel, avg, out, st);
        else
            print_metric(ctxp, NULL, NULL, "of all iTLB cache hits", 0);
    } else if (
        evsel->attr.type == PERF_TYPE_HW_CACHE &&
        evsel->attr.config ==  ( PERF_COUNT_HW_CACHE_LL |
                    ((PERF_COUNT_HW_CACHE_OP_READ) << 8) |
                     ((PERF_COUNT_HW_CACHE_RESULT_MISS) << 16))) {

        if (runtime_stat_n(st, STAT_LL_CACHE, ctx, cpu) != 0)
            print_ll_cache_misses(cpu, evsel, avg, out, st);
        else
            print_metric(ctxp, NULL, NULL, "of all LL-cache hits", 0);
    } else if (perf_evsel__match(evsel, HARDWARE, HW_CACHE_MISSES)) {
        total = runtime_stat_avg(st, STAT_CACHEREFS, ctx, cpu);

        if (total)
            ratio = avg * 100 / total;

        if (runtime_stat_n(st, STAT_CACHEREFS, ctx, cpu) != 0)
            print_metric(ctxp, NULL, "%8.3f %%",
                     "of all cache refs", ratio);
        else
            print_metric(ctxp, NULL, NULL, "of all cache refs", 0);
    } else if (perf_evsel__match(evsel, HARDWARE, HW_STALLED_CYCLES_FRONTEND)) {
        print_stalled_cycles_frontend(cpu, evsel, avg, out, st);
    } else if (perf_evsel__match(evsel, HARDWARE, HW_STALLED_CYCLES_BACKEND)) {
        print_stalled_cycles_backend(cpu, evsel, avg, out, st);
    } else if (perf_evsel__match(evsel, HARDWARE, HW_CPU_CYCLES)) {
        total = runtime_stat_avg(st, STAT_NSECS, 0, cpu);

        if (total) {
            ratio = avg / total;
            print_metric(ctxp, NULL, "%8.3f", "GHz", ratio);
        } else {
            print_metric(ctxp, NULL, NULL, "Ghz", 0);
        }
    } else if (perf_stat_evsel__is(evsel, CYCLES_IN_TX)) {
        total = runtime_stat_avg(st, STAT_CYCLES, ctx, cpu);

        if (total)
            print_metric(ctxp, NULL,
                    "%7.2f%%", "transactional cycles",
                    100.0 * (avg / total));
        else
            print_metric(ctxp, NULL, NULL, "transactional cycles",
                     0);
    } else if (perf_stat_evsel__is(evsel, CYCLES_IN_TX_CP)) {
        total = runtime_stat_avg(st, STAT_CYCLES, ctx, cpu);
        total2 = runtime_stat_avg(st, STAT_CYCLES_IN_TX, ctx, cpu);

        if (total2 < avg)
            total2 = avg;
        if (total)
            print_metric(ctxp, NULL, "%7.2f%%", "aborted cycles",
                100.0 * ((total2-avg) / total));
        else
            print_metric(ctxp, NULL, NULL, "aborted cycles", 0);
    } else if (perf_stat_evsel__is(evsel, TRANSACTION_START)) {
        total = runtime_stat_avg(st, STAT_CYCLES_IN_TX,
                     ctx, cpu);

        if (avg)
            ratio = total / avg;

        if (runtime_stat_n(st, STAT_CYCLES_IN_TX, ctx, cpu) != 0)
            print_metric(ctxp, NULL, "%8.0f",
                     "cycles / transaction", ratio);
        else
            print_metric(ctxp, NULL, NULL, "cycles / transaction",
                      0);
    } else if (perf_stat_evsel__is(evsel, ELISION_START)) {
        total = runtime_stat_avg(st, STAT_CYCLES_IN_TX,
                     ctx, cpu);

        if (avg)
            ratio = total / avg;

        print_metric(ctxp, NULL, "%8.0f", "cycles / elision", ratio);
    } else if (perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK) ||
           perf_evsel__match(evsel, SOFTWARE, SW_CPU_CLOCK)) {
        if ((ratio = avg_stats(&walltime_nsecs_stats)) != 0)
            print_metric(ctxp, NULL, "%8.3f", "CPUs utilized",
                     avg / ratio);
        else
            print_metric(ctxp, NULL, NULL, "CPUs utilized", 0);
    } else if (perf_stat_evsel__is(evsel, TOPDOWN_FETCH_BUBBLES)) {
        double fe_bound = td_fe_bound(ctx, cpu, st);

        if (fe_bound > 0.2)
            color = PERF_COLOR_RED;
        print_metric(ctxp, color, "%8.1f%%", "frontend bound",
                fe_bound * 100.);
    } else if (perf_stat_evsel__is(evsel, TOPDOWN_SLOTS_RETIRED)) {
        double retiring = td_retiring(ctx, cpu, st);

        if (retiring > 0.7)
            color = PERF_COLOR_GREEN;
        print_metric(ctxp, color, "%8.1f%%", "retiring",
                retiring * 100.);
    } else if (perf_stat_evsel__is(evsel, TOPDOWN_RECOVERY_BUBBLES)) {
        double bad_spec = td_bad_spec(ctx, cpu, st);

        if (bad_spec > 0.1)
            color = PERF_COLOR_RED;
        print_metric(ctxp, color, "%8.1f%%", "bad speculation",
                bad_spec * 100.);
    } else if (perf_stat_evsel__is(evsel, TOPDOWN_SLOTS_ISSUED)) {
        double be_bound = td_be_bound(ctx, cpu, st);
        const char *name = "backend bound";
        static int have_recovery_bubbles = -1;

        /* In case the CPU does not support topdown-recovery-bubbles */
        if (have_recovery_bubbles < 0)
            have_recovery_bubbles = pmu_have_event("cpu",
                    "topdown-recovery-bubbles");
        if (!have_recovery_bubbles)
            name = "backend bound/bad spec";

        if (be_bound > 0.2)
            color = PERF_COLOR_RED;
        if (td_total_slots(ctx, cpu, st) > 0)
            print_metric(ctxp, color, "%8.1f%%", name,
                    be_bound * 100.);
        else
            print_metric(ctxp, NULL, NULL, name, 0);
    } else if (evsel->metric_expr) {
        generic_metric(evsel->metric_expr, evsel->metric_events, evsel->name,
                evsel->metric_name, avg, cpu, out, st);
    } else if (runtime_stat_n(st, STAT_NSECS, 0, cpu) != 0) {
        char unit = 'M';
        char unit_buf[10];

        total = runtime_stat_avg(st, STAT_NSECS, 0, cpu);

        if (total)
            ratio = 1000.0 * avg / total;
        if (ratio < 0.001) {
            ratio *= 1000;
            unit = 'K';
        }
        snprintf(unit_buf, sizeof(unit_buf), "%c/sec", unit);
        print_metric(ctxp, NULL, "%8.3f", unit_buf, ratio);
    } else if (perf_stat_evsel__is(evsel, SMI_NUM)) {
        print_smi_cost(cpu, evsel, out, st);
    } else {
        num = 0;
    }

    if ((me = metricgroup__lookup(metric_events, evsel, false)) != NULL) {
        struct metric_expr *mexp;

        list_for_each_entry (mexp, &me->head, nd) {
            if (num++ > 0)
                out->new_line(ctxp);
            generic_metric(mexp->metric_expr, mexp->metric_events,
                    evsel->name, mexp->metric_name,
                    avg, cpu, out, st);
        }
    }
    if (num == 0)
        print_metric(ctxp, NULL, NULL, NULL, 0);
}