2 files changed, 24 insertions, 2 deletions

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 4025e18765c4..59324e7b3d8e 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -787,6 +787,7 @@ int parse_events(struct perf_evlist *evlist, const char *str, int unset __used)
 
         parse_events__flush_buffer(buffer);
         parse_events__delete_buffer(buffer);
+        parse_events_lex_destroy();
 
         if (!ret) {
                 int entries = idx - evlist->nr_entries;
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 1fcf1bbc5458..331d28a08dcb 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -1,5 +1,6 @@
 
 %option prefix="parse_events_"
+%option stack
 
 %{
 #include <errno.h>
@@ -50,6 +51,8 @@ static int term(int type)
 
 %}
 
+%x mem
+
 num_dec         [0-9]+
 num_hex         0x[a-fA-F0-9]+
 num_raw_hex     [a-fA-F0-9]+
@@ -105,13 +108,12 @@ config2			{ return term(PARSE_EVENTS__TERM_TYPE_CONFIG2); }
 period                  { return term(PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD); }
 branch_type             { return term(PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE); }
 
-mem:                    { return PE_PREFIX_MEM; }
+mem:                    { BEGIN(mem); return PE_PREFIX_MEM; }
 r{num_raw_hex}          { return raw(); }
 {num_dec}               { return value(10); }
 {num_hex}               { return value(16); }
 
 {modifier_event}        { return str(PE_MODIFIER_EVENT); }
-{modifier_bp}           { return str(PE_MODIFIER_BP); }
 {name}                  { return str(PE_NAME); }
 "/"                     { return '/'; }
 -                       { return '-'; }
@@ -119,6 +121,25 @@ r{num_raw_hex}		{ return raw(); }
 :                       { return ':'; }
 =                       { return '='; }
 
+<mem>{
+{modifier_bp}           { return str(PE_MODIFIER_BP); }
+:                       { return ':'; }
+{num_dec}               { return value(10); }
+{num_hex}               { return value(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); }
+        /*
+         * We destroy the scanner after reaching EOF,
+         * but anyway just to be sure get back to INIT state.
+         */
+<<EOF>>                 { BEGIN(INITIAL); }
+}
+
 %%
 
 int parse_events_wrap(void)