perf pmu: Make parser reentrant

By default bison uses global state for compatibility with yacc. Make
the parser reentrant so that it may be used in asynchronous and
multithreaded situations.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Gaosheng Cui <cuigaosheng1@huawei.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230406065224.2553640-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 78a407b42ad19909f78ccb9c75956390bd6784f9..96ef317bac413e89febc4d7e55f3a585b30a339e 100644 (file)
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -24,6 +24,8 @@
 #include "evsel.h"
 #include "pmu.h"
 #include "pmus.h"
+#include "pmu-bison.h"
+#include "pmu-flex.h"
 #include "parse-events.h"
 #include "print-events.h"
 #include "header.h"
@@ -57,9 +59,6 @@ struct perf_pmu_format {
        struct list_head list;
 };
 
-int perf_pmu_parse(struct list_head *list, char *name);
-extern FILE *perf_pmu_in;
-
 static bool hybrid_scanned;
 
 static struct perf_pmu *perf_pmu__find2(int dirfd, const char *name);
@@ -81,6 +80,8 @@ int perf_pmu__format_parse(int dirfd, struct list_head *head)
        while (!ret && (evt_ent = readdir(format_dir))) {
                char *name = evt_ent->d_name;
                int fd;
+               void *scanner;
+               FILE *file;
 
                if (!strcmp(name, ".") || !strcmp(name, ".."))
                        continue;
@@ -91,9 +92,22 @@ int perf_pmu__format_parse(int dirfd, struct list_head *head)
                if (fd < 0)
                        break;
 
-               perf_pmu_in = fdopen(fd, "r");
-               ret = perf_pmu_parse(head, name);
-               fclose(perf_pmu_in);
+               file = fdopen(fd, "r");
+               if (!file) {
+                       close(fd);
+                       break;
+               }
+
+               ret = perf_pmu_lex_init(&scanner);
+               if (ret) {
+                       fclose(file);
+                       break;
+               }
+
+               perf_pmu_set_in(file, scanner);
+               ret = perf_pmu_parse(head, name, scanner);
+               perf_pmu_lex_destroy(scanner);
+               fclose(file);
        }
 
        closedir(format_dir);

diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index 32c3a75bca0e1edacda8e49d228c70df6c442475..d53618c65c9244a9a5cdad70008aeae2b0b5688b 100644 (file)
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -206,7 +206,7 @@ int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms,
                          struct perf_pmu_info *info);
 struct list_head *perf_pmu__alias(struct perf_pmu *pmu,
                                  struct list_head *head_terms);
-void perf_pmu_error(struct list_head *list, char *name, char const *msg);
+void perf_pmu_error(struct list_head *list, char *name, void *scanner, char const *msg);
 
 int perf_pmu__new_format(struct list_head *list, char *name,
                         int config, unsigned long *bits);

diff --git a/tools/perf/util/pmu.l b/tools/perf/util/pmu.l
index 58b4926cfaca906dab6f6f85bd7f359c943f166d..67b247be693b1f1fdb5e18d2bec043c5cf315245 100644 (file)
--- a/tools/perf/util/pmu.l
+++ b/tools/perf/util/pmu.l
@@ -1,4 +1,6 @@
 %option prefix="perf_pmu_"
+%option reentrant
+%option bison-bridge
 
 %{
 #include <stdlib.h>
@@ -6,16 +8,21 @@
 #include "pmu.h"
 #include "pmu-bison.h"
 
-static int value(int base)
+char *perf_pmu_get_text(yyscan_t yyscanner);
+YYSTYPE *perf_pmu_get_lval(yyscan_t yyscanner);
+
+static int value(yyscan_t scanner, int base)
 {
+       YYSTYPE *yylval = perf_pmu_get_lval(scanner);
+       char *text = perf_pmu_get_text(scanner);
        long num;
 
        errno = 0;
-       num = strtoul(perf_pmu_text, NULL, base);
+       num = strtoul(text, NULL, base);
        if (errno)
                return PP_ERROR;
 
-       perf_pmu_lval.num = num;
+       yylval->num = num;
        return PP_VALUE;
 }
 
@@ -25,7 +32,7 @@ num_dec         [0-9]+
 
 %%
 
-{num_dec}      { return value(10); }
+{num_dec}      { return value(yyscanner, 10); }
 config         { return PP_CONFIG; }
 -              { return '-'; }
 :              { return ':'; }
@@ -35,7 +42,7 @@ config                { return PP_CONFIG; }
 
 %%
 
-int perf_pmu_wrap(void)
+int perf_pmu_wrap(void *scanner __maybe_unused)
 {
        return 1;
 }

diff --git a/tools/perf/util/pmu.y b/tools/perf/util/pmu.y
index e675d79a0274f7e8e24d65540b62443a9a4ec049..dff4e892ac4d87f1245b484d31469637b9bae540 100644 (file)
--- a/tools/perf/util/pmu.y
+++ b/tools/perf/util/pmu.y
@@ -1,6 +1,8 @@
-
+%define api.pure full
 %parse-param {struct list_head *format}
 %parse-param {char *name}
+%parse-param {void *scanner}
+%lex-param {void* scanner}
 
 %{
 
@@ -78,6 +80,7 @@ PP_VALUE
 
 void perf_pmu_error(struct list_head *list __maybe_unused,
                    char *name __maybe_unused,
+                   void *scanner __maybe_unused,
                    char const *msg __maybe_unused)
 {
 }