Re: [PATCH 10/19] perf metric: Add referenced metrics to hash data

Ian Rogers
2020-07-19T22:32:40Z

On Sun, Jul 19, 2020 at 11:14 AM Jiri Olsa <jolsa@kernel.org> wrote:
>
> Adding referenced metrics to the parsing context so they
> can be resolved during the metric processing.
>
> Adding expr__add_ref function to store referenced metrics
> into parse context.
>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>

Acked-by: Ian Rogers <irogers@google.com>

Thanks,
Ian

> ---
> tools/perf/util/expr.c | 54 +++++++++++++++++++++++++++++++++++
> tools/perf/util/expr.h | 13 ++++++++-
> tools/perf/util/stat-shadow.c | 20 +++++++++----
> 3 files changed, 80 insertions(+), 7 deletions(-)
>
> diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c
> index f726211f49d4..d3997c2b4a90 100644
> --- a/tools/perf/util/expr.c
> +++ b/tools/perf/util/expr.c
> @@ -4,10 +4,14 @@
> #include <errno.h>
> #include <stdlib.h>
> #include <string.h>
> +#include "metricgroup.h"
> +#include "debug.h"
> #include "expr.h"
> #include "expr-bison.h"
> #include "expr-flex.h"
> #include <linux/kernel.h>
> +#include <linux/zalloc.h>
> +#include <ctype.h>
>
> #ifdef PARSER_DEBUG
> extern int expr_debug;
> @@ -63,6 +67,7 @@ int expr__add_id_val(struct expr_parse_ctx *ctx, const char *id, double val)
> if (!data_ptr)
> return -ENOMEM;
> data_ptr->val = val;
> + data_ptr->is_ref = false;
>
> ret = hashmap__set(&ctx->ids, id, data_ptr,
> (const void **)&old_key, (void **)&old_data);
> @@ -73,6 +78,55 @@ int expr__add_id_val(struct expr_parse_ctx *ctx, const char *id, double val)
> return ret;
> }
>
> +int expr__add_ref(struct expr_parse_ctx *ctx, struct metric_ref *ref)
> +{
> + struct expr_id_data *data_ptr = NULL, *old_data = NULL;
> + char *old_key = NULL;
> + char *name, *p;
> + int ret;
> +
> + data_ptr = zalloc(sizeof(*data_ptr));
> + if (!data_ptr)
> + return -ENOMEM;
> +
> + name = strdup(ref->metric_name);
> + if (!name) {
> + free(data_ptr);
> + return -ENOMEM;
> + }
> +
> + /*
> + * The jevents tool converts all metric expressions
> + * to lowercase, including metric references, hence
> + * we need to add lowercase name for metric, so it's
> + * properly found.
> + */
> + for (p = name; *p; p++)
> + *p = tolower(*p);
> +
> + /*
> + * Intentionally passing just const char pointers,
> + * originally from 'struct pmu_event' object.
> + * We don't need to change them, so there's no
> + * need to create our own copy.
> + */
> + data_ptr->ref.metric_name = ref->metric_name;
> + data_ptr->ref.metric_expr = ref->metric_expr;
> + data_ptr->is_ref = true;
> +
> + ret = hashmap__set(&ctx->ids, name, data_ptr,
> + (const void **)&old_key, (void **)&old_data);
> + if (ret)
> + free(data_ptr);
> +
> + pr_debug2("adding ref metric %s: %s\n",
> + ref->metric_name, ref->metric_expr);
> +
> + free(old_key);
> + free(old_data);
> + return ret;
> +}
> +
> int expr__get_id(struct expr_parse_ctx *ctx, const char *id,
> struct expr_id_data **data)
> {
> diff --git a/tools/perf/util/expr.h b/tools/perf/util/expr.h
> index 2462abd0ac65..81d04ff7f857 100644
> --- a/tools/perf/util/expr.h
> +++ b/tools/perf/util/expr.h
> @@ -11,12 +11,22 @@
> #include "util/hashmap.h"
> //#endif
>
> +struct metric_ref;
> +
> struct expr_parse_ctx {
> struct hashmap ids;
> };
>
> struct expr_id_data {
> - double val;
> + union {
> + double val;
> + struct {
> + const char *metric_name;
> + const char *metric_expr;
> + } ref;
> + };
> +
> + bool is_ref;
> };
>
> struct expr_scanner_ctx {
> @@ -29,6 +39,7 @@ void expr__ctx_clear(struct expr_parse_ctx *ctx);
> void expr__del_id(struct expr_parse_ctx *ctx, const char *id);
> int expr__add_id(struct expr_parse_ctx *ctx, const char *id);
> int expr__add_id_val(struct expr_parse_ctx *ctx, const char *id, double val);
> +int expr__add_ref(struct expr_parse_ctx *ctx, struct metric_ref *ref);
> int expr__get_id(struct expr_parse_ctx *ctx, const char *id,
> struct expr_id_data **data);
> int expr__parse(double *final_val, struct expr_parse_ctx *ctx,
> diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
> index fc9ac4b4218e..e1ba6c1b916a 100644
> --- a/tools/perf/util/stat-shadow.c
> +++ b/tools/perf/util/stat-shadow.c
> @@ -731,13 +731,14 @@ static void print_smi_cost(struct perf_stat_config *config,
> }
>
> static int prepare_metric(struct evsel **metric_events,
> + struct metric_ref *metric_refs,
> struct expr_parse_ctx *pctx,
> int cpu,
> struct runtime_stat *st)
> {
> double scale;
> char *n, *pn;
> - int i;
> + int i, j, ret;
>
> expr__ctx_init(pctx);
> for (i = 0; metric_events[i]; i++) {
> @@ -778,12 +779,19 @@ static int prepare_metric(struct evsel **metric_events,
> expr__add_id_val(pctx, n, avg_stats(stats)*scale);
> }
>
> + for (j = 0; metric_refs && metric_refs[j].metric_name; j++) {
> + ret = expr__add_ref(pctx, &metric_refs[j]);
> + if (ret)
> + return ret;
> + }
> +
> return i;
> }
>
> static void generic_metric(struct perf_stat_config *config,
> const char *metric_expr,
> struct evsel **metric_events,
> + struct metric_ref *metric_refs,
> char *name,
> const char *metric_name,
> const char *metric_unit,
> @@ -798,7 +806,7 @@ static void generic_metric(struct perf_stat_config *config,
> int i;
> void *ctxp = out->ctx;
>
> - i = prepare_metric(metric_events, &pctx, cpu, st);
> + i = prepare_metric(metric_events, metric_refs, &pctx, cpu, st);
> if (i < 0)
> return;
>
> @@ -847,7 +855,7 @@ double test_generic_metric(struct metric_expr *mexp, int cpu, struct runtime_sta
> struct expr_parse_ctx pctx;
> double ratio;
>
> - if (prepare_metric(mexp->metric_events, &pctx, cpu, st) < 0)
> + if (prepare_metric(mexp->metric_events, mexp->metric_refs, &pctx, cpu, st) < 0)
> return 0.;
>
> if (expr__parse(&ratio, &pctx, mexp->metric_expr, 1))
> @@ -1064,8 +1072,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> else
> print_metric(config, ctxp, NULL, NULL, name, 0);
> } else if (evsel->metric_expr) {
> - generic_metric(config, evsel->metric_expr, evsel->metric_events, evsel->name,
> - evsel->metric_name, NULL, 1, cpu, out, st);
> + generic_metric(config, evsel->metric_expr, evsel->metric_events, NULL,
> + evsel->name, evsel->metric_name, NULL, 1, cpu, out, st);
> } else if (runtime_stat_n(st, STAT_NSECS, 0, cpu) != 0) {
> char unit = 'M';
> char unit_buf[10];
> @@ -1093,7 +1101,7 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> if (num++ > 0)
> out->new_line(config, ctxp);
> generic_metric(config, mexp->metric_expr, mexp->metric_events,
> - evsel->name, mexp->metric_name,
> + mexp->metric_refs, evsel->name, mexp->metric_name,
> mexp->metric_unit, mexp->runtime, cpu, out, st);
> }
> }
> --
> 2.25.4
>