Re: [RFC 03/12] perf event action: Add parsing const integer expr support

Arnaldo Carvalho de Melo
2024-11-28T20:25:36Z

On Thu, Nov 28, 2024 at 09:35:44PM +0800, Yang Jihong wrote:
> Support parsing of constant integer expression.
>
> Signed-off-by: Yang Jihong <yangjihong@bytedance.com>
> ---
> tools/perf/util/parse-action.c | 52 ++++++++++++++++++++++++++++++++++
> tools/perf/util/parse-action.h | 1 +
> tools/perf/util/parse-action.l | 19 +++++++++++++
> tools/perf/util/parse-action.y | 13 ++++++++-
> 4 files changed, 84 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/parse-action.c b/tools/perf/util/parse-action.c
> index 391546bf3d73..3b10cf9f99b3 100644
> --- a/tools/perf/util/parse-action.c
> +++ b/tools/perf/util/parse-action.c
> @@ -7,6 +7,7 @@
> *
> * Supported expressions:
> * - constant:
> + * - integer

And now there are alignment differences and no : ?

> */
>
> #include "util/debug.h"
> @@ -118,7 +119,58 @@ void event_actions__free(void)
> (void)event_actions__for_each_expr_safe(do_action_free, NULL, false);
> }
>
> +static int expr_const_int_new(struct evtact_expr *expr, void *data, int size)
> +{
> + if (data == NULL ||
> + (size != sizeof(int)
> + && size != sizeof(long) && size != sizeof(long long))) {

&& should be at the end of the previous line, just like you did with the
|| at the end of the first line

> + pr_err("expr_const_int size invalid: %d\n", size);
> + return -EINVAL;
> + }
> +
> + expr->priv = malloc(sizeof(long long));
> + if (expr->priv == NULL) {
> + pr_err("exp_ const_int malloc failed\n");
> + return -ENOMEM;
> + }
> +
> + if (size == sizeof(int))
> + *(unsigned long long *)(expr->priv) = *(unsigned int *)data;
> + else if (size == sizeof(long))
> + *(unsigned long long *)(expr->priv) = *(unsigned long *)data;
> + else if (size == sizeof(long long))
> + *(unsigned long long *)(expr->priv) = *(unsigned long long *)data;
> +
> + INIT_LIST_HEAD(&expr->opnds);
> + return 0;
> +}
> +
> +static void expr_const_int_free(struct evtact_expr *expr)
> +{
> + zfree(&expr->priv);
> +}
> +
> +static int expr_const_int_eval(struct evtact_expr *expr,
> + void *in __maybe_unused, int in_size __maybe_unused,
> + void **out, int *out_size)
> +{
> + if (out != NULL)
> + *out = expr->priv;
> +
> + if (out_size != NULL)
> + *out_size = sizeof(long long);
> +
> + return 0;
> +}
> +
> +static struct evtact_expr_ops expr_const_int_ops = {
> + .new = expr_const_int_new,
> + .free = expr_const_int_free,
> + .eval = expr_const_int_eval,
> +};
> +
> static struct evtact_expr_ops *expr_const_ops_list[EVTACT_EXPR_CONST_TYPE_MAX] = {
> + [EVTACT_EXPR_CONST_TYPE_INT] = &expr_const_int_ops,
> };
>
> static int expr_const_set_ops(struct evtact_expr *expr, u32 opcode)
> diff --git a/tools/perf/util/parse-action.h b/tools/perf/util/parse-action.h
> index 47bd75264dee..ac81278c590e 100644
> --- a/tools/perf/util/parse-action.h
> +++ b/tools/perf/util/parse-action.h
> @@ -14,6 +14,7 @@ enum evtact_expr_type {
> };
>
> enum evtact_expr_const_type {
> + EVTACT_EXPR_CONST_TYPE_INT,
> EVTACT_EXPR_CONST_TYPE_MAX,
> };
>
> diff --git a/tools/perf/util/parse-action.l b/tools/perf/util/parse-action.l
> index 3cb72de50372..9237399a11ac 100644
> --- a/tools/perf/util/parse-action.l
> +++ b/tools/perf/util/parse-action.l
> @@ -13,13 +13,32 @@
> #include "parse-action.h"
> #include "parse-action-bison.h"
>
> +static int value(int base)
> +{
> + unsigned long long num;
> +
> + errno = 0;
> + num = strtoul(parse_action_text, NULL, base);
> + if (errno) {
> + pr_err("parse_action malloc number failed\n");
> + return ERROR;
> + }
> +
> + parse_action_lval.num = num;
> + return NUMBER;
> +}
> +
> %}
>
> +num_dec [0-9]+
> +num_hex 0[xX][0-9a-fA-F]+
> space [ \t]
> ident [_a-zA-Z][_a-zA-Z0-9]*
>
> %%
>
> +{num_dec} { return value(10); }
> +{num_hex} { return value(16); }
> {space} { }
>
> ";" { return SEMI; }
> diff --git a/tools/perf/util/parse-action.y b/tools/perf/util/parse-action.y
> index fade9d093d4a..51e77e54f157 100644
> --- a/tools/perf/util/parse-action.y
> +++ b/tools/perf/util/parse-action.y
> @@ -17,6 +17,8 @@
> #include "util/debug.h"
> #include "util/parse-action.h"
>
> +#define expr_id(t, o) evtact_expr_id_encode(EVTACT_EXPR_TYPE_##t, EVTACT_EXPR_##t##_TYPE_##o)
> +
> int parse_action_lex(void);
>
> static void parse_action_error(struct list_head *expr __maybe_unused,
> @@ -32,13 +34,15 @@ static void parse_action_error(struct list_head *expr __maybe_unused,
> char *str;
> struct evtact_expr *expr;
> struct list_head *list;
> + unsigned long long num;
> }
>
> -%token IDENT ERROR
> +%token IDENT ERROR NUMBER
> %token SEMI
> %type <expr> action_term expr_term
> %destructor { parse_action_expr__free($$); } <expr>
> %type <str> IDENT
> +%type <num> NUMBER
>
> %%
>
> @@ -65,6 +69,13 @@ expr_term
> }
>
> expr_term:
> +NUMBER
> +{
> + $$ = parse_action_expr__new(expr_id(CONST, INT), NULL, (void *)&$1, sizeof($1));
> + if ($$ == NULL)
> + YYERROR;
> +}
> +|
> IDENT
> {
> $$ = NULL;
> --
> 2.25.1