[PATCH 2/5] perf, tool: Make the event parser reentrantable

[Jiri Olsa <jolsa@redhat.com>]

Making the event parser reentrantable by creating separate
scanner for each parsing. The scanner is passed to the bison
as and argument to the lexer.

Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
---
 tools/perf/util/parse-events.c |   35 ++++++++----
 tools/perf/util/parse-events.h |    2 +-
 tools/perf/util/parse-events.l |  116 +++++++++++++++++++++++-----------------
 tools/perf/util/parse-events.y |    9 ++-
 4 files changed, 98 insertions(+), 64 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 25e5479..64d936b 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -11,6 +11,7 @@
 #include "cache.h"
 #include "header.h"
 #include "debugfs.h"
+#include "parse-events-bison.h"
 #include "parse-events-flex.h"
 #include "pmu.h"
 
@@ -26,7 +27,7 @@ struct event_symbol {
 #ifdef PARSER_DEBUG
 extern int parse_events_debug;
 #endif
-int parse_events_parse(void *data);
+int parse_events_parse(void *data, void *scanner);
 
 #define CHW(x) .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_##x
 #define CSW(x) .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_##x
@@ -792,26 +793,38 @@ int parse_events_modifier(struct list_head *list, char *str)
 	return 0;
 }
 
-int parse_events(struct perf_evlist *evlist, const char *str, int unset __used)
+static int parse_events__scanner(const char *str, void *data)
 {
-	struct parse_events_data__events data = {
-		.list = LIST_HEAD_INIT(data.list),
-		.idx  = evlist->nr_entries,
-	};
 	YY_BUFFER_STATE buffer;
+	void *scanner;
 	int ret;
 
-	buffer = parse_events__scan_string(str);
+	ret = parse_events_lex_init(&scanner);
+	if (ret)
+		return ret;
+
+	buffer = parse_events__scan_string(str, scanner);
 
 #ifdef PARSER_DEBUG
 	parse_events_debug = 1;
 #endif
-	ret = parse_events_parse(&data);
+	ret = parse_events_parse(data, scanner);
+
+	parse_events__flush_buffer(buffer, scanner);
+	parse_events__delete_buffer(buffer, scanner);
+	parse_events_lex_destroy(scanner);
+	return ret;
+}
 
-	parse_events__flush_buffer(buffer);
-	parse_events__delete_buffer(buffer);
-	parse_events_lex_destroy();
+int parse_events(struct perf_evlist *evlist, const char *str, int unset __used)
+{
+	struct parse_events_data__events data = {
+		.list = LIST_HEAD_INIT(data.list),
+		.idx  = evlist->nr_entries,
+	};
+	int ret;
 
+	ret = parse_events__scanner(str, &data);
 	if (!ret) {
 		int entries = data.idx - evlist->nr_entries;
 		perf_evlist__splice_list_tail(evlist, &data.list, entries);
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index dc3c83a..fa2b19b 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -88,7 +88,7 @@ int parse_events_add_pmu(struct list_head **list, int *idx,
 			 char *pmu , struct list_head *head_config);
 void parse_events_update_lists(struct list_head *list_event,
 			       struct list_head *list_all);
-void parse_events_error(void *data, char const *msg);
+void parse_events_error(void *data, void *scanner, char const *msg);
 int parse_events__test(void);
 
 void print_events(const char *event_glob);
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 618a8e7..329794e 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -1,4 +1,6 @@
 
+%option reentrant
+%option bison-bridge
 %option prefix="parse_events_"
 %option stack
 
@@ -8,7 +10,10 @@
 #include "parse-events-bison.h"
 #include "parse-events.h"
 
-static int __value(char *str, int base, int token)
+char *parse_events_get_text(yyscan_t yyscanner);
+YYSTYPE *parse_events_get_lval(yyscan_t yyscanner);
+
+static int __value(YYSTYPE *yylval, char *str, int base, int token)
 {
 	long num;
 
@@ -17,35 +22,48 @@ static int __value(char *str, int base, int token)
 	if (errno)
 		return PE_ERROR;
 
-	parse_events_lval.num = num;
+	yylval->num = num;
 	return token;
 }
 
-static int value(int base)
+static int value(yyscan_t scanner, int base)
 {
-	return __value(parse_events_text, base, PE_VALUE);
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+	char *text = parse_events_get_text(scanner);
+
+	return __value(yylval, text, base, PE_VALUE);
 }
 
-static int raw(void)
+static int raw(yyscan_t scanner)
 {
-	return __value(parse_events_text + 1, 16, PE_RAW);
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+	char *text = parse_events_get_text(scanner);
+
+	return __value(yylval, text + 1, 16, PE_RAW);
 }
 
-static int str(int token)
+static int str(yyscan_t scanner, int token)
 {
-	parse_events_lval.str = strdup(parse_events_text);
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+	char *text = parse_events_get_text(scanner);
+
+	yylval->str = strdup(text);
 	return token;
 }
 
-static int sym(int type, int config)
+static int sym(yyscan_t scanner, int type, int config)
 {
-	parse_events_lval.num = (type << 16) + config;
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+
+	yylval->num = (type << 16) + config;
 	return PE_VALUE_SYM;
 }
 
-static int term(int type)
+static int term(yyscan_t scanner, int type)
 {
-	parse_events_lval.num = type;
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+
+	yylval->num = type;
 	return PE_TERM;
 }
 
@@ -61,25 +79,25 @@ modifier_event	[ukhpGH]{1,8}
 modifier_bp	[rwx]
 
 %%
-cpu-cycles|cycles				{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_CPU_CYCLES); }
-stalled-cycles-frontend|idle-cycles-frontend	{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); }
-stalled-cycles-backend|idle-cycles-backend	{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); }
-instructions					{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_INSTRUCTIONS); }
-cache-references				{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_CACHE_REFERENCES); }
-cache-misses					{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_CACHE_MISSES); }
-branch-instructions|branches			{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); }
-branch-misses					{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_BRANCH_MISSES); }
-bus-cycles					{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_BUS_CYCLES); }
-ref-cycles					{ return sym(PERF_TYPE_HARDWARE, PERF_COUNT_HW_REF_CPU_CYCLES); }
-cpu-clock					{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CPU_CLOCK); }
-task-clock					{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_TASK_CLOCK); }
-page-faults|faults				{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS); }
-minor-faults					{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS_MIN); }
-major-faults					{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS_MAJ); }
-context-switches|cs				{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CONTEXT_SWITCHES); }
-cpu-migrations|migrations			{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CPU_MIGRATIONS); }
-alignment-faults				{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_ALIGNMENT_FAULTS); }
-emulation-faults				{ return sym(PERF_TYPE_SOFTWARE, PERF_COUNT_SW_EMULATION_FAULTS); }
+cpu-cycles|cycles				{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_CPU_CYCLES); }
+stalled-cycles-frontend|idle-cycles-frontend	{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); }
+stalled-cycles-backend|idle-cycles-backend	{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); }
+instructions					{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_INSTRUCTIONS); }
+cache-references				{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_CACHE_REFERENCES); }
+cache-misses					{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_CACHE_MISSES); }
+branch-instructions|branches			{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); }
+branch-misses					{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_BRANCH_MISSES); }
+bus-cycles					{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_BUS_CYCLES); }
+ref-cycles					{ return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_REF_CPU_CYCLES); }
+cpu-clock					{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CPU_CLOCK); }
+task-clock					{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_TASK_CLOCK); }
+page-faults|faults				{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS); }
+minor-faults					{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS_MIN); }
+major-faults					{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS_MAJ); }
+context-switches|cs				{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CONTEXT_SWITCHES); }
+cpu-migrations|migrations			{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CPU_MIGRATIONS); }
+alignment-faults				{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_ALIGNMENT_FAULTS); }
+emulation-faults				{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_EMULATION_FAULTS); }
 
 L1-dcache|l1-d|l1d|L1-data		|
 L1-icache|l1-i|l1i|L1-instruction	|
@@ -87,14 +105,14 @@ LLC|L2					|
 dTLB|d-tlb|Data-TLB			|
 iTLB|i-tlb|Instruction-TLB		|
 branch|branches|bpu|btb|bpc		|
-node					{ return str(PE_NAME_CACHE_TYPE); }
+node					{ return str(yyscanner, PE_NAME_CACHE_TYPE); }
 
 load|loads|read				|
 store|stores|write			|
 prefetch|prefetches			|
 speculative-read|speculative-load	|
 refs|Reference|ops|access		|
-misses|miss				{ return str(PE_NAME_CACHE_OP_RESULT); }
+misses|miss				{ return str(yyscanner, PE_NAME_CACHE_OP_RESULT); }
 
 	/*
 	 * These are event config hardcoded term names to be specified
@@ -102,20 +120,20 @@ misses|miss				{ return str(PE_NAME_CACHE_OP_RESULT); }
 	 * so we can put them here directly. In case the we have a conflict
 	 * in future, this needs to go into '//' condition block.
 	 */
-config			{ return term(PARSE_EVENTS__TERM_TYPE_CONFIG); }
-config1			{ return term(PARSE_EVENTS__TERM_TYPE_CONFIG1); }
-config2			{ return term(PARSE_EVENTS__TERM_TYPE_CONFIG2); }
-name			{ return term(PARSE_EVENTS__TERM_TYPE_NAME); }
-period			{ return term(PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD); }
-branch_type		{ return term(PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE); }
+config			{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_CONFIG); }
+config1			{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_CONFIG1); }
+config2			{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_CONFIG2); }
+name			{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NAME); }
+period			{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD); }
+branch_type		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE); }
 
 mem:			{ BEGIN(mem); return PE_PREFIX_MEM; }
-r{num_raw_hex}		{ return raw(); }
-{num_dec}		{ return value(10); }
-{num_hex}		{ return value(16); }
+r{num_raw_hex}		{ return raw(yyscanner); }
+{num_dec}		{ return value(yyscanner, 10); }
+{num_hex}		{ return value(yyscanner, 16); }
 
-{modifier_event}	{ return str(PE_MODIFIER_EVENT); }
-{name}			{ return str(PE_NAME); }
+{modifier_event}	{ return str(yyscanner, PE_MODIFIER_EVENT); }
+{name}			{ return str(yyscanner, PE_NAME); }
 "/"			{ return '/'; }
 -			{ return '-'; }
 ,			{ return ','; }
@@ -123,17 +141,17 @@ r{num_raw_hex}		{ return raw(); }
 =			{ return '='; }
 
 <mem>{
-{modifier_bp}		{ return str(PE_MODIFIER_BP); }
+{modifier_bp}		{ return str(yyscanner, PE_MODIFIER_BP); }
 :			{ return ':'; }
-{num_dec}		{ return value(10); }
-{num_hex}		{ return value(16); }
+{num_dec}		{ return value(yyscanner, 10); }
+{num_hex}		{ return value(yyscanner, 16); }
 	/*
 	 * We need to separate 'mem:' scanner part, in order to get specific
 	 * modifier bits parsed out. Otherwise we would need to handle PE_NAME
 	 * and we'd need to parse it manually. During the escape from <mem>
 	 * state we need to put the escaping char back, so we dont miss it.
 	 */
-.			{ unput(*parse_events_text); BEGIN(INITIAL); }
+.			{ unput(*yytext); BEGIN(INITIAL); }
 	/*
 	 * We destroy the scanner after reaching EOF,
 	 * but anyway just to be sure get back to INIT state.
@@ -143,7 +161,7 @@ r{num_raw_hex}		{ return raw(); }
 
 %%
 
-int parse_events_wrap(void)
+int parse_events_wrap(void *scanner __used)
 {
 	return 1;
 }
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index e533bf7..2a93d5c 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -1,6 +1,8 @@
-
+%pure-parser
 %name-prefix "parse_events_"
 %parse-param {void *_data}
+%parse-param {void *scanner}
+%lex-param {void* scanner}
 
 %{
 
@@ -11,8 +13,9 @@
 #include "types.h"
 #include "util.h"
 #include "parse-events.h"
+#include "parse-events-bison.h"
 
-extern int parse_events_lex (void);
+extern int parse_events_lex (YYSTYPE* lvalp, void* scanner);
 
 #define ABORT_ON(val) \
 do { \
@@ -286,7 +289,7 @@ sep_slash_dc: '/' | ':' |
 
 %%
 
-void parse_events_error(void *data __used,
+void parse_events_error(void *data __used, void *scanner __used,
 			char const *msg __used)
 {
 }
-- 
1.7.7.6