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perf lock: Fix parse_lock_type which only retrieve one lock flag

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`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: 9.313 [sec]

         9.313976 usecs/op
           107365 ops/sec
   contended   total wait     max wait     avg wait         type   caller

         176      1.65 ms     19.43 us      9.38 us        mutex   pipe_read+0x57
          34    180.14 us     10.93 us      5.30 us        mutex   pipe_write+0x50
           7     77.48 us     16.09 us     11.07 us        mutex   do_epoll_wait+0x24d
           7     74.70 us     13.50 us     10.67 us        mutex   do_epoll_wait+0x24d
           3     35.97 us     14.44 us     11.99 us     rwlock:W   ep_done_scan+0x2d
           3     35.00 us     12.23 us     11.66 us     rwlock:W   do_epoll_wait+0x255
           2     15.88 us     11.96 us      7.94 us     rwlock:W   do_epoll_wait+0x47c
           1     15.23 us     15.23 us     15.23 us     rwlock:W   do_epoll_wait+0x4d0
           1     14.26 us     14.26 us     14.26 us     rwlock:W   ep_done_scan+0x2d
           2     14.00 us      7.99 us      7.00 us        mutex   pipe_read+0x282
           1     12.29 us     12.29 us     12.29 us     rwlock:R   ep_poll_callback+0x35
           1     12.02 us     12.02 us     12.02 us     rwlock:W   do_epoll_ctl+0xb65
           1     10.25 us     10.25 us     10.25 us     rwlock:R   ep_poll_callback+0x35
           1      7.86 us      7.86 us      7.86 us        mutex   do_epoll_ctl+0x6c1
           1      5.04 us      5.04 us      5.04 us        mutex   do_epoll_ctl+0x3d4

[namhyung: Add a comment and rename to 'mutex:spin' for consistency

Fixes: d783ea8f62 ("perf lock contention: Simplify parse_lock_type()")
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Cc: nick.forrington@arm.com
Link: https://lore.kernel.org/r/20250116235838.2769691-1-ctshao@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
This commit is contained in:
Chun-Tse Shao 2025-01-16 15:58:14 -08:00 committed by Namhyung Kim
parent 83196dd349
commit 1be9264158
1 changed files with 41 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
tools/perf/builtin-lock.c
View File

@ -1484,8 +1484,8 @@ static const struct {
{ LCB_F_PERCPU | LCB_F_WRITE, "pcpu-sem:W", "percpu-rwsem" },
{ LCB_F_MUTEX, "mutex", "mutex" },
{ LCB_F_MUTEX | LCB_F_SPIN, "mutex", "mutex" },
/* alias for get_type_flag() */
{ LCB_F_MUTEX | LCB_F_SPIN, "mutex-spin", "mutex" },
/* alias for optimistic spinning only */
{ LCB_F_MUTEX | LCB_F_SPIN, "mutex:spin", "mutex-spin" },
};
static const char *get_type_str(unsigned int flags)
@ -1510,19 +1510,6 @@ static const char *get_type_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].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].str, str))
return lock_type_table[i].flags;
}
return UINT_MAX;
}
static void lock_filter_finish(void)
{
zfree(&filters.types);
@ -2254,29 +2241,58 @@ 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 `str` in `lock_type_table` if it contains ':'. */
if (strchr(tok, ':')) {
for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
if (!strcmp(lock_type_table[i].str, 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 `name` in `lock_type_table`.
* Single lock name could contain multiple flags.
*/
for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
if (!strcmp(lock_type_table[i].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)