[PATCH v3 2/2] perf lock: Fix parse_lock_type which only retrieve one lock flag

[Chun-Tse Shao <ctshao@google.com>]

`parse_lock_type` can only add the first lock flag in `lock_type_table`
given input `str`. For example, for `Y rwlock`, it only adds `rwlock:R`
into this perf session. Another example is for `-Y mutex`, it only adds
the mutex without `LCB_F_SPIN` flag. The patch fixes this issue, makes
sure both `rwlock:R` and `rwlock:W` will be added with `-Y rwlock`, and
so on.

Testing:
  $ ./perf lock con -ab -Y mutex,rwlock -- perf bench sched pipe
  # Running 'sched/pipe' benchmark:
  # Executed 1000000 pipe operations between two processes

       Total time: 8.425 [sec]

         8.425402 usecs/op
           118688 ops/sec
   contended   total wait     max wait     avg wait         type   caller

         194      1.68 ms     44.16 us      8.66 us        mutex   pipe_read+0x57
          10    423.03 us     44.27 us     42.30 us     rwlock:W   do_exit+0x365
          54    254.67 us     58.87 us      4.72 us        mutex   pipe_write+0x50
          21    146.64 us     11.54 us      6.98 us        mutex   pipe_read+0x282
          10    141.27 us     20.62 us     14.13 us     rwlock:W   release_task+0x6f
           5     58.92 us     16.37 us     11.78 us        mutex   do_epoll_wait+0x24d
           3     29.81 us     17.66 us      9.94 us        mutex   do_epoll_ctl+0x6c1
           4     26.82 us     11.02 us      6.70 us        mutex   do_epoll_wait+0x24d
           2     18.32 us     12.49 us      9.16 us     rwlock:W   do_epoll_wait+0x255
           1     11.34 us     11.34 us     11.34 us     rwlock:W   ep_done_scan+0x2d
           1     11.02 us     11.02 us     11.02 us     rwlock:R   mm_update_next_owner+0x4e
           1     10.60 us     10.60 us     10.60 us     rwlock:W   do_epoll_ctl+0xb65
           1      9.90 us      9.90 us      9.90 us     rwlock:W   do_exit+0x365

Fixes: d783ea8f62c4 ("perf lock contention: Simplify parse_lock_type()")
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
---
 tools/perf/builtin-lock.c | 68 ++++++++++++++++++++++++++-------------
 1 file changed, 45 insertions(+), 23 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index c528aff1c9d5..c1870c287580 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -1622,19 +1622,6 @@ static const char *get_type_lock_name(unsigned int flags)
 	return "unknown";
 }
 
-static unsigned int get_type_flag(const char *str)
-{
-	for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
-		if (!strcmp(lock_type_table[i].flags_name, str))
-			return lock_type_table[i].flags;
-	}
-	for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
-		if (!strcmp(lock_type_table[i].lock_name, str))
-			return lock_type_table[i].flags;
-	}
-	return UINT_MAX;
-}
-
 static void lock_filter_finish(void)
 {
 	zfree(&filters.types);
@@ -2356,29 +2343,64 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
 			   int unset __maybe_unused)
 {
 	char *s, *tmp, *tok;
-	int ret = 0;
 
 	s = strdup(str);
 	if (s == NULL)
 		return -1;
 
 	for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
-		unsigned int flags = get_type_flag(tok);
+		bool found = false;
 
-		if (flags == -1U) {
-			pr_err("Unknown lock flags: %s\n", tok);
-			ret = -1;
-			break;
+		/* `tok` is a flags name if it contains ':'. */
+		if (strchr(tok, ':')) {
+			for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
+				if (!strcmp(lock_type_table[i].flags_name, tok) &&
+				    add_lock_type(lock_type_table[i].flags)) {
+					found = true;
+					break;
+				}
+			}
+
+			if (!found) {
+				pr_err("Unknown lock flags name: %s\n", tok);
+				free(s);
+				return -1;
+			}
+
+			continue;
 		}
 
-		if (!add_lock_type(flags)) {
-			ret = -1;
-			break;
+		/*
+		 * Otherwise `tok` is a lock name.
+		 * Single lock name could contain multiple flags.
+		 */
+		/*
+		 * By documentation, `percpu-rwmem` should be `pcpu-sem`.
+		 * For backward compatibility, we replace `pcpu-sem` with `percpu-rwmem`.
+		 */
+		if (!strcmp(tok, "pcpu-sem"))
+			tok = (char *)"percpu-rwsem";
+
+		for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
+			if (!strcmp(lock_type_table[i].lock_name, tok)) {
+				if (add_lock_type(lock_type_table[i].flags)) {
+					found = true;
+				} else {
+					free(s);
+					return -1;
+				}
+			}
+		}
+
+		if (!found) {
+			pr_err("Unknown lock name: %s\n", tok);
+			free(s);
+			return -1;
 		}
 	}
 
 	free(s);
-	return ret;
+	return 0;
 }
 
 static bool add_lock_addr(unsigned long addr)
-- 
2.47.0.338.g60cca15819-goog