Re: [PATCH v7 04/16] perf tp_pmu: Factor existing tracepoint logic to new file

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Mon, Jul 14, 2025 at 09:43:52AM -0700, Ian Rogers wrote:
> Start the creation of a tracepoint PMU abstraction. Tracepoint events
> don't follow the regular sysfs perf conventions. Eventually the new
> PMU abstraction will bridge the gap so tracepoint events look more
> like regular perf ones.
> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/util/Build          |   1 +
>  tools/perf/util/evsel.c        |  21 +----
>  tools/perf/util/parse-events.c | 147 ++++++++++++++-------------------
>  tools/perf/util/tp_pmu.c       |  95 +++++++++++++++++++++
>  tools/perf/util/tp_pmu.h       |  12 +++
>  5 files changed, 170 insertions(+), 106 deletions(-)
>  create mode 100644 tools/perf/util/tp_pmu.c
>  create mode 100644 tools/perf/util/tp_pmu.h
> 
> diff --git a/tools/perf/util/Build b/tools/perf/util/Build
> index 12bc01c843b2..4959e7a990e4 100644
> --- a/tools/perf/util/Build
> +++ b/tools/perf/util/Build
> @@ -88,6 +88,7 @@ perf-util-y += pmu-bison.o
>  perf-util-y += drm_pmu.o
>  perf-util-y += hwmon_pmu.o
>  perf-util-y += tool_pmu.o
> +perf-util-y += tp_pmu.o
>  perf-util-y += svghelper.o
>  perf-util-y += trace-event-info.o
>  perf-util-y += trace-event-scripting.o
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index 3896a04d90af..5a1d19b4e5cd 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -59,6 +59,7 @@
>  #include "drm_pmu.h"
>  #include "hwmon_pmu.h"
>  #include "tool_pmu.h"
> +#include "tp_pmu.h"
>  #include "rlimit.h"
>  #include "../perf-sys.h"
>  #include "util/parse-branch-options.h"
> @@ -571,24 +572,6 @@ struct evsel *evsel__clone(struct evsel *dest, struct evsel *orig)
>  	return NULL;
>  }
>  
> -static int trace_event__id(const char *sys, const char *name)
> -{
> -	char *tp_dir = get_events_file(sys);
> -	char path[PATH_MAX];
> -	int id, err;
> -
> -	if (!tp_dir)
> -		return -1;
> -
> -	scnprintf(path, PATH_MAX, "%s/%s/id", tp_dir, name);
> -	put_events_file(tp_dir);
> -	err = filename__read_int(path, &id);
> -	if (err)
> -		return err;
> -
> -	return id;
> -}
> -
>  /*
>   * Returns pointer with encoded error via <linux/err.h> interface.
>   */
> @@ -622,7 +605,7 @@ struct evsel *evsel__newtp_idx(const char *sys, const char *name, int idx, bool
>  	event_attr_init(&attr);
>  
>  	if (format) {
> -		id = trace_event__id(sys, name);
> +		id = tp_pmu__id(sys, name);
>  		if (id < 0) {
>  			err = id;
>  			goto out_free;
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index 1ae481c9802b..f19541ca5268 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -17,13 +17,12 @@
>  #include "string2.h"
>  #include "strbuf.h"
>  #include "debug.h"
> -#include <api/fs/tracing_path.h>
> -#include <api/io_dir.h>
>  #include <perf/cpumap.h>
>  #include <util/parse-events-bison.h>
>  #include <util/parse-events-flex.h>
>  #include "pmu.h"
>  #include "pmus.h"
> +#include "tp_pmu.h"
>  #include "asm/bug.h"
>  #include "ui/ui.h"
>  #include "util/parse-branch-options.h"
> @@ -33,6 +32,7 @@
>  #include "util/stat.h"
>  #include "util/util.h"
>  #include "tracepoint.h"
> +#include <api/fs/tracing_path.h>
>  
>  #define MAX_NAME_LEN 100
>  
> @@ -558,105 +558,82 @@ static int add_tracepoint(struct parse_events_state *parse_state,
>  	return 0;
>  }
>  
> -static int add_tracepoint_multi_event(struct parse_events_state *parse_state,
> -				      struct list_head *list,
> -				      const char *sys_name, const char *evt_name,
> -				      struct parse_events_error *err,
> -				      struct parse_events_terms *head_config, YYLTYPE *loc)
> -{
> -	char *evt_path;
> -	struct io_dirent64 *evt_ent;
> -	struct io_dir evt_dir;
> -	int ret = 0, found = 0;
> -
> -	evt_path = get_events_file(sys_name);
> -	if (!evt_path) {
> -		tracepoint_error(err, errno, sys_name, evt_name, loc->first_column);
> -		return -1;
> -	}
> -	io_dir__init(&evt_dir, open(evt_path, O_CLOEXEC | O_DIRECTORY | O_RDONLY));
> -	if (evt_dir.dirfd < 0) {
> -		put_events_file(evt_path);
> -		tracepoint_error(err, errno, sys_name, evt_name, loc->first_column);
> -		return -1;
> -	}
> +struct add_tracepoint_multi_args {
> +	struct parse_events_state *parse_state;
> +	struct list_head *list;
> +	const char *sys_glob;
> +	const char *evt_glob;
> +	struct parse_events_error *err;
> +	struct parse_events_terms *head_config;
> +	YYLTYPE *loc;
> +	int found;
> +};
>  
> -	while (!ret && (evt_ent = io_dir__readdir(&evt_dir))) {
> -		if (!strcmp(evt_ent->d_name, ".")
> -		    || !strcmp(evt_ent->d_name, "..")
> -		    || !strcmp(evt_ent->d_name, "enable")
> -		    || !strcmp(evt_ent->d_name, "filter"))
> -			continue;
> +static int add_tracepoint_multi_event_cb(void *state, const char *sys_name, const char *evt_name)
> +{
> +	struct add_tracepoint_multi_args *args = state;
> +	int ret;
>  
> -		if (!strglobmatch(evt_ent->d_name, evt_name))
> -			continue;
> +	if (!strglobmatch(evt_name, args->evt_glob))
> +		return 0;
>  
> -		found++;
> +	args->found++;
> +	ret = add_tracepoint(args->parse_state, args->list, sys_name, evt_name,
> +			     args->err, args->head_config, args->loc);
>  
> -		ret = add_tracepoint(parse_state, list, sys_name, evt_ent->d_name,
> -				     err, head_config, loc);
> -	}
> +	return ret;
> +}
>  
> -	if (!found) {
> -		tracepoint_error(err, ENOENT, sys_name, evt_name, loc->first_column);
> -		ret = -1;
> +static int add_tracepoint_multi_event(struct add_tracepoint_multi_args *args, const char *sys_name)
> +{
> +	if (strpbrk(args->evt_glob, "*?") == NULL) {
> +		/* Not a glob. */
> +		args->found++;
> +		return add_tracepoint(args->parse_state, args->list, sys_name, args->evt_glob,
> +				      args->err, args->head_config, args->loc);
>  	}
>  
> -	put_events_file(evt_path);
> -	close(evt_dir.dirfd);
> -	return ret;
> +	return tp_pmu__for_each_tp_event(sys_name, args, add_tracepoint_multi_event_cb);
>  }
>  
> -static int add_tracepoint_event(struct parse_events_state *parse_state,
> -				struct list_head *list,
> -				const char *sys_name, const char *evt_name,
> -				struct parse_events_error *err,
> -				struct parse_events_terms *head_config, YYLTYPE *loc)
> +static int add_tracepoint_multi_sys_cb(void *state, const char *sys_name)
>  {
> -	return strpbrk(evt_name, "*?") ?
> -		add_tracepoint_multi_event(parse_state, list, sys_name, evt_name,
> -					   err, head_config, loc) :
> -		add_tracepoint(parse_state, list, sys_name, evt_name,
> -			       err, head_config, loc);
> +	struct add_tracepoint_multi_args *args = state;
> +
> +	if (!strglobmatch(sys_name, args->sys_glob))
> +		return 0;
> +
> +	return add_tracepoint_multi_event(args, sys_name);
>  }
>  
>  static int add_tracepoint_multi_sys(struct parse_events_state *parse_state,
>  				    struct list_head *list,
> -				    const char *sys_name, const char *evt_name,
> +				    const char *sys_glob, const char *evt_glob,
>  				    struct parse_events_error *err,
>  				    struct parse_events_terms *head_config, YYLTYPE *loc)
>  {
> -	struct io_dirent64 *events_ent;
> -	struct io_dir events_dir;
> -	int ret = 0;
> -	char *events_dir_path = get_tracing_file("events");
> +	struct add_tracepoint_multi_args args = {
> +		.parse_state = parse_state,
> +		.list = list,
> +		.sys_glob = sys_glob,
> +		.evt_glob = evt_glob,
> +		.err = err,
> +		.head_config = head_config,
> +		.loc = loc,
> +		.found = 0,
> +	};
> +	int ret;
>  
> -	if (!events_dir_path) {
> -		tracepoint_error(err, errno, sys_name, evt_name, loc->first_column);
> -		return -1;
> +	if (strpbrk(sys_glob, "*?") == NULL) {
> +		/* Not a glob. */
> +		ret = add_tracepoint_multi_event(&args, sys_glob);
> +	} else {
> +		ret = tp_pmu__for_each_tp_sys(&args, add_tracepoint_multi_sys_cb);
>  	}
> -	io_dir__init(&events_dir, open(events_dir_path, O_CLOEXEC | O_DIRECTORY | O_RDONLY));
> -	put_events_file(events_dir_path);
> -	if (events_dir.dirfd < 0) {
> -		tracepoint_error(err, errno, sys_name, evt_name, loc->first_column);
> -		return -1;
> +	if (args.found == 0) {
> +		tracepoint_error(err, ENOENT, sys_glob, evt_glob, loc->first_column);
> +		return -ENOENT;
>  	}
> -
> -	while (!ret && (events_ent = io_dir__readdir(&events_dir))) {
> -		if (!strcmp(events_ent->d_name, ".")
> -		    || !strcmp(events_ent->d_name, "..")
> -		    || !strcmp(events_ent->d_name, "enable")
> -		    || !strcmp(events_ent->d_name, "header_event")
> -		    || !strcmp(events_ent->d_name, "header_page"))
> -			continue;
> -
> -		if (!strglobmatch(events_ent->d_name, sys_name))
> -			continue;
> -
> -		ret = add_tracepoint_event(parse_state, list, events_ent->d_name,
> -					   evt_name, err, head_config, loc);
> -	}
> -	close(events_dir.dirfd);
>  	return ret;
>  }
>  
> @@ -1348,12 +1325,8 @@ int parse_events_add_tracepoint(struct parse_events_state *parse_state,
>  			return -EINVAL;
>  	}
>  
> -	if (strpbrk(sys, "*?"))
> -		return add_tracepoint_multi_sys(parse_state, list, sys, event,
> -						err, head_config, loc);
> -	else
> -		return add_tracepoint_event(parse_state, list, sys, event,
> -					    err, head_config, loc);
> +	return add_tracepoint_multi_sys(parse_state, list, sys, event,
> +					err, head_config, loc);
>  }
>  
>  static int __parse_events_add_numeric(struct parse_events_state *parse_state,
> diff --git a/tools/perf/util/tp_pmu.c b/tools/perf/util/tp_pmu.c
> new file mode 100644
> index 000000000000..fd83164f8763
> --- /dev/null
> +++ b/tools/perf/util/tp_pmu.c
> @@ -0,0 +1,95 @@
> +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
> +#include "tp_pmu.h"
> +#include <api/fs/fs.h>
> +#include <api/fs/tracing_path.h>
> +#include <api/io_dir.h>
> +#include <linux/kernel.h>
> +#include <errno.h>
> +#include <string.h>
> +
> +int tp_pmu__id(const char *sys, const char *name)
> +{
> +	char *tp_dir = get_events_file(sys);
> +	char path[PATH_MAX];
> +	int id, err;
> +
> +	if (!tp_dir)
> +		return -1;
> +
> +	scnprintf(path, PATH_MAX, "%s/%s/id", tp_dir, name);
> +	put_events_file(tp_dir);
> +	err = filename__read_int(path, &id);
> +	if (err)
> +		return err;
> +
> +	return id;
> +}
> +
> +
> +int tp_pmu__for_each_tp_event(const char *sys, void *state, tp_event_callback cb)
> +{
> +	char *evt_path;
> +	struct io_dirent64 *evt_ent;
> +	struct io_dir evt_dir;
> +	int ret = 0;
> +
> +	evt_path = get_events_file(sys);
> +	if (!evt_path)
> +		return -errno;
> +
> +	io_dir__init(&evt_dir, open(evt_path, O_CLOEXEC | O_DIRECTORY | O_RDONLY));
> +	if (evt_dir.dirfd < 0) {
> +		ret = -errno;
> +		put_events_file(evt_path);
> +		return ret;
> +	}
> +	put_events_file(evt_path);
> +
> +	while (!ret && (evt_ent = io_dir__readdir(&evt_dir))) {
> +		if (!strcmp(evt_ent->d_name, ".")
> +		    || !strcmp(evt_ent->d_name, "..")
> +		    || !strcmp(evt_ent->d_name, "enable")
> +		    || !strcmp(evt_ent->d_name, "filter"))
> +			continue;

I see that the previous code had this style, but since we're moving it
to this separate file, can we have the || at the end of the lines
please?

> +
> +		ret = cb(state, sys, evt_ent->d_name);
> +		if (ret)
> +			break;
> +	}
> +	close(evt_dir.dirfd);
> +	return ret;
> +}
> +
> +int tp_pmu__for_each_tp_sys(void *state, tp_sys_callback cb)
> +{
> +	struct io_dirent64 *events_ent;
> +	struct io_dir events_dir;
> +	int ret = 0;
> +	char *events_dir_path = get_tracing_file("events");
> +
> +	if (!events_dir_path)
> +		return -errno;
> +
> +	io_dir__init(&events_dir, open(events_dir_path, O_CLOEXEC | O_DIRECTORY | O_RDONLY));
> +	if (events_dir.dirfd < 0) {
> +		ret = -errno;
> +		put_events_file(events_dir_path);
> +		return ret;
> +	}
> +	put_events_file(events_dir_path);
> +
> +	while (!ret && (events_ent = io_dir__readdir(&events_dir))) {
> +		if (!strcmp(events_ent->d_name, ".")
> +		    || !strcmp(events_ent->d_name, "..")
> +		    || !strcmp(events_ent->d_name, "enable")
> +		    || !strcmp(events_ent->d_name, "header_event")
> +		    || !strcmp(events_ent->d_name, "header_page"))
> +			continue;

Ditto

> +
> +		ret = cb(state, events_ent->d_name);
> +		if (ret)
> +			break;
> +	}
> +	close(events_dir.dirfd);
> +	return ret;
> +}
> diff --git a/tools/perf/util/tp_pmu.h b/tools/perf/util/tp_pmu.h
> new file mode 100644
> index 000000000000..49537303bd73
> --- /dev/null
> +++ b/tools/perf/util/tp_pmu.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
> +#ifndef __TP_PMU_H
> +#define __TP_PMU_H
> +
> +typedef int (*tp_sys_callback)(void *state, const char *sys_name);
> +typedef int (*tp_event_callback)(void *state, const char *sys_name, const char *evt_name);
> +
> +int tp_pmu__id(const char *sys, const char *name);
> +int tp_pmu__for_each_tp_event(const char *sys, void *state, tp_event_callback cb);
> +int tp_pmu__for_each_tp_sys(void *state, tp_sys_callback cb);
> +
> +#endif /* __TP_PMU_H */
> -- 
> 2.50.0.727.gbf7dc18ff4-goog
>