linux-perf-users.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ian Rogers <irogers@google.com>
To: Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
	Ian Rogers <irogers@google.com>,
	Adrian Hunter <adrian.hunter@intel.com>,
	James Clark <james.clark@arm.com>,
	Kan Liang <kan.liang@linux.intel.com>,
	John Garry <john.g.garry@oracle.com>,
	Kajol Jain <kjain@linux.ibm.com>,
	Jing Zhang <renyu.zj@linux.alibaba.com>,
	Ravi Bangoria <ravi.bangoria@amd.com>,
	Rob Herring <robh@kernel.org>,
	Gaosheng Cui <cuigaosheng1@huawei.com>,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v1 17/25] perf pmu: Parse sysfs events directly from a file
Date: Wed, 23 Aug 2023 01:08:20 -0700	[thread overview]
Message-ID: <20230823080828.1460376-18-irogers@google.com> (raw)
In-Reply-To: <20230823080828.1460376-1-irogers@google.com>

Rather than read a sysfs events file into a 256 byte char buffer, pass
the FILE* directly to the lex/yacc parser. This avoids there being a
maximum events file size. While changing the API, constify some
arguments to remove unnecessary casts. Allocating the read buffer
decreases the performance of pmu-scan by around 3%.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/arch/x86/util/intel-pt.c |  2 +-
 tools/perf/tests/parse-events.c     |  2 +-
 tools/perf/util/parse-events.c      | 18 +++++++----
 tools/perf/util/parse-events.h      |  3 +-
 tools/perf/util/pmu.c               | 48 ++++++++++-------------------
 5 files changed, 33 insertions(+), 40 deletions(-)

diff --git a/tools/perf/arch/x86/util/intel-pt.c b/tools/perf/arch/x86/util/intel-pt.c
index 27944c15ac14..31807791589e 100644
--- a/tools/perf/arch/x86/util/intel-pt.c
+++ b/tools/perf/arch/x86/util/intel-pt.c
@@ -74,7 +74,7 @@ static int intel_pt_parse_terms_with_default(struct perf_pmu *pmu,
 
 	INIT_LIST_HEAD(terms);
 
-	err = parse_events_terms(terms, str);
+	err = parse_events_terms(terms, str, /*input=*/ NULL);
 	if (err)
 		goto out_free;
 
diff --git a/tools/perf/tests/parse-events.c b/tools/perf/tests/parse-events.c
index 658fb9599d95..d86076d575ed 100644
--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -2472,7 +2472,7 @@ static int test_term(const struct terms_test *t)
 
 	INIT_LIST_HEAD(&terms);
 
-	ret = parse_events_terms(&terms, t->str);
+	ret = parse_events_terms(&terms, t->str, /*input=*/ NULL);
 	if (ret) {
 		pr_debug("failed to parse terms '%s', err %d\n",
 			 t->str , ret);
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 781747bedc3e..c71e135d7335 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1715,6 +1715,7 @@ int parse_events_name(struct list_head *list, const char *name)
 }
 
 static int parse_events__scanner(const char *str,
+				 FILE *input,
 				 struct parse_events_state *parse_state)
 {
 	YY_BUFFER_STATE buffer;
@@ -1725,7 +1726,10 @@ static int parse_events__scanner(const char *str,
 	if (ret)
 		return ret;
 
-	buffer = parse_events__scan_string(str, scanner);
+	if (str)
+		buffer = parse_events__scan_string(str, scanner);
+	else
+	        parse_events_set_in(input, scanner);
 
 #ifdef PARSER_DEBUG
 	parse_events_debug = 1;
@@ -1733,8 +1737,10 @@ static int parse_events__scanner(const char *str,
 #endif
 	ret = parse_events_parse(parse_state, scanner);
 
-	parse_events__flush_buffer(buffer, scanner);
-	parse_events__delete_buffer(buffer, scanner);
+	if (str) {
+		parse_events__flush_buffer(buffer, scanner);
+		parse_events__delete_buffer(buffer, scanner);
+	}
 	parse_events_lex_destroy(scanner);
 	return ret;
 }
@@ -1742,7 +1748,7 @@ static int parse_events__scanner(const char *str,
 /*
  * parse event config string, return a list of event terms.
  */
-int parse_events_terms(struct list_head *terms, const char *str)
+int parse_events_terms(struct list_head *terms, const char *str, FILE *input)
 {
 	struct parse_events_state parse_state = {
 		.terms  = NULL,
@@ -1750,7 +1756,7 @@ int parse_events_terms(struct list_head *terms, const char *str)
 	};
 	int ret;
 
-	ret = parse_events__scanner(str, &parse_state);
+	ret = parse_events__scanner(str, input, &parse_state);
 
 	if (!ret) {
 		list_splice(parse_state.terms, terms);
@@ -2001,7 +2007,7 @@ int __parse_events(struct evlist *evlist, const char *str, const char *pmu_filte
 	};
 	int ret, ret2;
 
-	ret = parse_events__scanner(str, &parse_state);
+	ret = parse_events__scanner(str, /*input=*/ NULL, &parse_state);
 
 	if (!ret && list_empty(&parse_state.list)) {
 		WARN_ONCE(true, "WARNING: event parser found nothing\n");
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 411f69b2ac3a..c7f779420723 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -9,6 +9,7 @@
 #include <stdbool.h>
 #include <linux/types.h>
 #include <linux/perf_event.h>
+#include <stdio.h>
 #include <string.h>
 
 struct evsel;
@@ -42,7 +43,7 @@ static inline int parse_events(struct evlist *evlist, const char *str,
 
 int parse_event(struct evlist *evlist, const char *str);
 
-int parse_events_terms(struct list_head *terms, const char *str);
+int parse_events_terms(struct list_head *terms, const char *str, FILE *input);
 int parse_filter(const struct option *opt, const char *str, int unset);
 int exclude_perf(const struct option *opt, const char *arg, int unset);
 
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 284962c133b3..6db14967ded9 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -276,7 +276,7 @@ int perf_pmu__convert_scale(const char *scale, char **end, double *sval)
 	return ret;
 }
 
-static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, int dirfd, char *name)
+static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, int dirfd, const char *name)
 {
 	struct stat st;
 	ssize_t sret;
@@ -308,7 +308,7 @@ static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, int dirfd, char *
 	return ret;
 }
 
-static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, int dirfd, char *name)
+static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, int dirfd, const char *name)
 {
 	char path[PATH_MAX];
 	ssize_t sret;
@@ -339,7 +339,7 @@ static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, int dirfd, char *n
 }
 
 static int
-perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, int dirfd, char *name)
+perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, int dirfd, const char *name)
 {
 	char path[PATH_MAX];
 	int fd;
@@ -357,7 +357,7 @@ perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, int dirfd, char *name)
 }
 
 static int perf_pmu__parse_snapshot(struct perf_pmu_alias *alias,
-				    int dirfd, char *name)
+				    int dirfd, const char *name)
 {
 	char path[PATH_MAX];
 	int fd;
@@ -450,8 +450,9 @@ static bool perf_pmu_merge_alias(struct perf_pmu_alias *newalias,
 	return false;
 }
 
-static int __perf_pmu__new_alias(struct list_head *list, int dirfd, char *name,
-				 char *desc, char *val, const struct pmu_event *pe)
+static int perf_pmu__new_alias(struct list_head *list, int dirfd, const char *name,
+				const char *desc, const char *val, FILE *val_fd,
+				const struct pmu_event *pe)
 {
 	struct parse_events_term *term;
 	struct perf_pmu_alias *alias;
@@ -480,7 +481,7 @@ static int __perf_pmu__new_alias(struct list_head *list, int dirfd, char *name,
 	alias->snapshot = false;
 	alias->deprecated = deprecated;
 
-	ret = parse_events_terms(&alias->terms, val);
+	ret = parse_events_terms(&alias->terms, val, val_fd);
 	if (ret) {
 		pr_err("Cannot parse alias %s: %d\n", val, ret);
 		free(alias);
@@ -537,23 +538,6 @@ static int __perf_pmu__new_alias(struct list_head *list, int dirfd, char *name,
 	return 0;
 }
 
-static int perf_pmu__new_alias(struct list_head *list, int dirfd, char *name, FILE *file)
-{
-	char buf[256];
-	int ret;
-
-	ret = fread(buf, 1, sizeof(buf), file);
-	if (ret == 0)
-		return -EINVAL;
-
-	buf[ret] = 0;
-
-	/* Remove trailing newline from sysfs file */
-	strim(buf);
-
-	return __perf_pmu__new_alias(list, dirfd, name, NULL, buf, NULL);
-}
-
 static inline bool pmu_alias_info_file(char *name)
 {
 	size_t len;
@@ -609,7 +593,8 @@ static int pmu_aliases_parse(int dirfd, struct list_head *head)
 			continue;
 		}
 
-		if (perf_pmu__new_alias(head, dirfd, name, file) < 0)
+		if (perf_pmu__new_alias(head, dirfd, name, /*desc=*/ NULL,
+					/*val=*/ NULL, file, /*pe=*/ NULL) < 0)
 			pr_debug("Cannot set up %s\n", name);
 		fclose(file);
 	}
@@ -862,7 +847,7 @@ static int pmu_add_cpu_aliases_map_callback(const struct pmu_event *pe,
 	struct list_head *head = vdata;
 
 	/* need type casts to override 'const' */
-	__perf_pmu__new_alias(head, -1, (char *)pe->name, (char *)pe->desc, (char *)pe->event, pe);
+	perf_pmu__new_alias(head, -1, pe->name, pe->desc, pe->event, /*val_fd=*/ NULL, pe);
 	return 0;
 }
 
@@ -903,11 +888,12 @@ static int pmu_add_sys_aliases_iter_fn(const struct pmu_event *pe,
 
 	if (!strcmp(pmu->id, pe->compat) &&
 	    pmu_uncore_alias_match(pe->pmu, pmu->name)) {
-		__perf_pmu__new_alias(idata->head, -1,
-				      (char *)pe->name,
-				      (char *)pe->desc,
-				      (char *)pe->event,
-				      pe);
+		perf_pmu__new_alias(idata->head, -1,
+				pe->name,
+				pe->desc,
+				pe->event,
+				/*val_fd=*/ NULL,
+				pe);
 	}
 
 	return 0;
-- 
2.42.0.rc1.204.g551eb34607-goog


  parent reply	other threads:[~2023-08-23 10:15 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-23  8:08 [PATCH v1 00/25] Lazily load PMU data Ian Rogers
2023-08-23  8:08 ` [PATCH v1 01/25] perf script ibs: Remove unused include Ian Rogers
2023-08-23  8:08 ` [PATCH v1 02/25] perf pmu: Avoid a path name copy Ian Rogers
2023-08-23  8:08 ` [PATCH v1 03/25] perf pmu: Move perf_pmu__set_format to pmu.y Ian Rogers
2023-08-23  8:08 ` [PATCH v1 04/25] perf pmu: Reduce scope of perf_pmu_error Ian Rogers
2023-08-23  8:08 ` [PATCH v1 05/25] perf pmu: Avoid passing format list to perf_pmu__config_terms Ian Rogers
2023-08-23  8:08 ` [PATCH v1 06/25] perf pmu: Avoid passing format list to perf_pmu__format_type Ian Rogers
2023-08-23  8:08 ` [PATCH v1 07/25] perf pmu: Avoid passing format list to perf_pmu__format_bits Ian Rogers
2023-08-23  8:08 ` [PATCH v1 08/25] perf pmu: Pass PMU rather than aliases and format Ian Rogers
2023-08-23  8:08 ` [PATCH v1 09/25] perf pmu: Make the loading of formats lazy Ian Rogers
2023-08-23 11:54   ` Arnaldo Carvalho de Melo
2023-08-24  2:23     ` Ian Rogers
2023-08-23  8:08 ` [PATCH v1 10/25] perf pmu: Abstract alias/event struct Ian Rogers
2023-08-23  8:08 ` [PATCH v1 11/25] perf pmu-events: Add extra underscore to function names Ian Rogers
2023-08-23  8:08 ` [PATCH v1 12/25] perf jevents: Group events by PMU Ian Rogers
2023-08-23  8:08 ` [PATCH v1 13/25] perf parse-events: Improve error message for double setting Ian Rogers
2023-08-23  8:08 ` [PATCH v1 14/25] perf s390 s390_cpumcfdg_dump: Don't scan all PMUs Ian Rogers
2023-08-23  8:08 ` [PATCH v1 15/25] perf pmu-events: Reduce processed events by passing PMU Ian Rogers
2023-08-23  8:08 ` [PATCH v1 16/25] perf pmu-events: Add pmu_events_table__find_event Ian Rogers
2023-08-23  8:08 ` Ian Rogers [this message]
2023-08-23  8:08 ` [PATCH v1 18/25] perf pmu: Prefer passing pmu to aliases list Ian Rogers
2023-08-23  8:08 ` [PATCH v1 19/25] perf pmu: Merge json events with sysfs at load time Ian Rogers
2023-08-23  8:08 ` [PATCH v1 20/25] perf pmu: Cache json events table Ian Rogers
2023-08-23  8:08 ` [PATCH v1 21/25] perf pmu: Lazily add json events Ian Rogers
2023-08-23  8:08 ` [PATCH v1 22/25] perf pmu: Scan type early to fail an invalid PMU quickly Ian Rogers
2023-08-23  8:08 ` [PATCH v1 23/25] perf pmu: Be lazy about loading event info files from sysfs Ian Rogers
2023-08-23  8:08 ` [PATCH v1 24/25] perf pmu: Lazily load sysfs aliases Ian Rogers
2023-08-23  8:08 ` [PATCH v1 25/25] perf jevents: Sort strings in the big C string to reduce faults Ian Rogers
2023-08-23  8:12 ` [PATCH v1 00/25] Lazily load PMU data Ian Rogers
2023-08-23 15:56 ` Arnaldo Carvalho de Melo
     [not found]   ` <CAP-5=fXYDMo6GgSaLuC3YMNr66yAXLMyZoAOMpdgmMb=xazCOw@mail.gmail.com>
2023-08-23 17:11     ` Arnaldo Carvalho de Melo
2023-08-23 17:40       ` Ian Rogers

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230823080828.1460376-18-irogers@google.com \
    --to=irogers@google.com \
    --cc=acme@kernel.org \
    --cc=adrian.hunter@intel.com \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=cuigaosheng1@huawei.com \
    --cc=james.clark@arm.com \
    --cc=john.g.garry@oracle.com \
    --cc=jolsa@kernel.org \
    --cc=kan.liang@linux.intel.com \
    --cc=kjain@linux.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-perf-users@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=peterz@infradead.org \
    --cc=ravi.bangoria@amd.com \
    --cc=renyu.zj@linux.alibaba.com \
    --cc=robh@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).