[PATCH v4 1/3] perf lock: Fix parse_lock_type which only retrieve one lock flag

[PATCH v4 1/3] perf lock: Fix parse_lock_type which only retrieve one lock flag

[Chun-Tse Shao]

`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

Fixes: d783ea8f62c4 ("perf lock contention: Simplify parse_lock_type()")
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
---
 tools/perf/builtin-lock.c | 64 ++++++++++++++++++++++++---------------
 1 file changed, 39 insertions(+), 25 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 062e2b56a2ab..7e36bbe3cb80 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -1591,8 +1591,6 @@ 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" },
 };
 
 static const char *get_type_str(unsigned int flags)
@@ -1617,19 +1615,6 @@ 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);
@@ -2350,29 +2335,58 @@ 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)
-- 
2.47.0.338.g60cca15819-goog

[PATCH v4 2/3] perf lock: Fix the wrong name percpu-rwsem

[Chun-Tse Shao]

In `perf lock --help`, the name of `percpu-rwsem` should be
`pcpu-rwsem`. This patch fixes the naming in `lock_type_table`, and also
replaces the mismatched name `percpu-rwsem` before parsing it for
backward compatibility.

Tested `./perf lock con -ab -Y pcpu-sem` and `./perf lock con -ab -Y
percpu-rwsem`

Fixes: 4f701063bfa2 ("perf lock contention: Show lock type with address")
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
---
 tools/perf/builtin-lock.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 7e36bbe3cb80..264acfa648e4 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -1587,8 +1587,8 @@ static const struct {
 	{ LCB_F_RT,			"rt-mutex",	"rt-mutex" },
 	{ LCB_F_RT | LCB_F_READ,	"rwlock-rt:R",	"rwlock-rt" },
 	{ LCB_F_RT | LCB_F_WRITE,	"rwlock-rt:W",	"rwlock-rt" },
-	{ LCB_F_PERCPU | LCB_F_READ,	"pcpu-sem:R",	"percpu-rwsem" },
-	{ LCB_F_PERCPU | LCB_F_WRITE,	"pcpu-sem:W",	"percpu-rwsem" },
+	{ LCB_F_PERCPU | LCB_F_READ,	"pcpu-sem:R",	"pcpu-sem" },
+	{ LCB_F_PERCPU | LCB_F_WRITE,	"pcpu-sem:W",	"pcpu-sem" },
 	{ LCB_F_MUTEX,			"mutex",	"mutex" },
 	{ LCB_F_MUTEX | LCB_F_SPIN,	"mutex",	"mutex" },
 };
@@ -2365,7 +2365,11 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
 		/*
 		 * Otherwise `tok` is `name` in `lock_type_table`.
 		 * Single lock name could contain multiple flags.
+		 * By documentation, `percpu-rwmem` should be `pcpu-sem`.
+		 * For backward compatibility, we replace `percpu-rwmem` with `pcpu-sem`.
 		 */
+		if (!strcmp(tok, "percpu-rwsem"))
+			tok = (char *)"pcpu-sem";
 		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)) {
-- 
2.47.0.338.g60cca15819-goog

[PATCH v4 3/3] perf lock: Rename fields in lock_type_table

[Chun-Tse Shao]

`lock_type_table` contains `name` and `str` which can be confusing.
Rename them to `flags_name` and `lock_name` and add descriptions to
enhance understanding.
Tested by building perf for x86.

Signed-off-by: Chun-Tse Shao <ctshao@google.com>
---
 tools/perf/builtin-lock.c | 33 +++++++++++++++++++--------------
 1 file changed, 19 insertions(+), 14 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 264acfa648e4..991de468e0f1 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -1575,8 +1575,13 @@ static void sort_result(void)
 
 static const struct {
 	unsigned int flags;
-	const char *str;
-	const char *name;
+	/*
+	 * Name of the lock flags (access), with delimeter ':'.
+	 * For example, rwsem:R of rwsem:W.
+	 */
+	const char *flags_name;
+	/* Name of the lock (type), for example, rwlock or rwsem. */
+	const char *lock_name;
 } lock_type_table[] = {
 	{ 0,				"semaphore",	"semaphore" },
 	{ LCB_F_SPIN,			"spinlock",	"spinlock" },
@@ -1593,24 +1598,24 @@ static const struct {
 	{ LCB_F_MUTEX | LCB_F_SPIN,	"mutex",	"mutex" },
 };
 
-static const char *get_type_str(unsigned int flags)
+static const char *get_type_flags_name(unsigned int flags)
 {
 	flags &= LCB_F_MAX_FLAGS - 1;
 
 	for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
 		if (lock_type_table[i].flags == flags)
-			return lock_type_table[i].str;
+			return lock_type_table[i].flags_name;
 	}
 	return "unknown";
 }
 
-static const char *get_type_name(unsigned int flags)
+static const char *get_type_lock_name(unsigned int flags)
 {
 	flags &= LCB_F_MAX_FLAGS - 1;
 
 	for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
 		if (lock_type_table[i].flags == flags)
-			return lock_type_table[i].name;
+			return lock_type_table[i].lock_name;
 	}
 	return "unknown";
 }
@@ -1717,7 +1722,7 @@ static void print_lock_stat_stdio(struct lock_contention *con, struct lock_stat
 
 	switch (aggr_mode) {
 	case LOCK_AGGR_CALLER:
-		fprintf(lock_output, "  %10s   %s\n", get_type_str(st->flags), st->name);
+		fprintf(lock_output, "  %10s   %s\n", get_type_flags_name(st->flags), st->name);
 		break;
 	case LOCK_AGGR_TASK:
 		pid = st->addr;
@@ -1727,7 +1732,7 @@ static void print_lock_stat_stdio(struct lock_contention *con, struct lock_stat
 		break;
 	case LOCK_AGGR_ADDR:
 		fprintf(lock_output, "  %016llx   %s (%s)\n", (unsigned long long)st->addr,
-			st->name, get_type_name(st->flags));
+			st->name, get_type_lock_name(st->flags));
 		break;
 	case LOCK_AGGR_CGROUP:
 		fprintf(lock_output, "  %s\n", st->name);
@@ -1768,7 +1773,7 @@ static void print_lock_stat_csv(struct lock_contention *con, struct lock_stat *s
 
 	switch (aggr_mode) {
 	case LOCK_AGGR_CALLER:
-		fprintf(lock_output, "%s%s %s", get_type_str(st->flags), sep, st->name);
+		fprintf(lock_output, "%s%s %s", get_type_flags_name(st->flags), sep, st->name);
 		if (verbose <= 0)
 			fprintf(lock_output, "\n");
 		break;
@@ -1780,7 +1785,7 @@ static void print_lock_stat_csv(struct lock_contention *con, struct lock_stat *s
 		break;
 	case LOCK_AGGR_ADDR:
 		fprintf(lock_output, "%llx%s %s%s %s\n", (unsigned long long)st->addr, sep,
-			st->name, sep, get_type_name(st->flags));
+			st->name, sep, get_type_lock_name(st->flags));
 		break;
 	case LOCK_AGGR_CGROUP:
 		fprintf(lock_output, "%s\n",st->name);
@@ -2343,10 +2348,10 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
 	for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
 		bool found = false;
 
-		/* `tok` is `str` in `lock_type_table` if it contains ':'. */
+		/* `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].str, tok) &&
+				if (!strcmp(lock_type_table[i].flags_name, tok) &&
 				    add_lock_type(lock_type_table[i].flags)) {
 					found = true;
 					break;
@@ -2363,7 +2368,7 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
 		}
 
 		/*
-		 * Otherwise `tok` is `name` in `lock_type_table`.
+		 * 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 `percpu-rwmem` with `pcpu-sem`.
@@ -2371,7 +2376,7 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
 		if (!strcmp(tok, "percpu-rwsem"))
 			tok = (char *)"pcpu-sem";
 		for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) {
-			if (!strcmp(lock_type_table[i].name, tok)) {
+			if (!strcmp(lock_type_table[i].lock_name, tok)) {
 				if (add_lock_type(lock_type_table[i].flags)) {
 					found = true;
 				} else {
-- 
2.47.0.338.g60cca15819-goog

Re: [PATCH v4 1/3] perf lock: Fix parse_lock_type which only retrieve one lock flag

[Namhyung Kim]

On Mon, Dec 09, 2024 at 12:01:00PM -0800, Chun-Tse Shao wrote:
> `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
> 
> Fixes: d783ea8f62c4 ("perf lock contention: Simplify parse_lock_type()")
> Signed-off-by: Chun-Tse Shao <ctshao@google.com>

Reviewed-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> ---
>  tools/perf/builtin-lock.c | 64 ++++++++++++++++++++++++---------------
>  1 file changed, 39 insertions(+), 25 deletions(-)
> 
> diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
> index 062e2b56a2ab..7e36bbe3cb80 100644
> --- a/tools/perf/builtin-lock.c
> +++ b/tools/perf/builtin-lock.c
> @@ -1591,8 +1591,6 @@ 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" },
>  };
>  
>  static const char *get_type_str(unsigned int flags)
> @@ -1617,19 +1615,6 @@ 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);
> @@ -2350,29 +2335,58 @@ 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)
> -- 
> 2.47.0.338.g60cca15819-goog
> 

Re: [PATCH v4 2/3] perf lock: Fix the wrong name percpu-rwsem

[Namhyung Kim]

On Mon, Dec 09, 2024 at 12:01:01PM -0800, Chun-Tse Shao wrote:
> In `perf lock --help`, the name of `percpu-rwsem` should be
> `pcpu-rwsem`. This patch fixes the naming in `lock_type_table`, and also
> replaces the mismatched name `percpu-rwsem` before parsing it for
> backward compatibility.
> 
> Tested `./perf lock con -ab -Y pcpu-sem` and `./perf lock con -ab -Y
> percpu-rwsem`
> 
> Fixes: 4f701063bfa2 ("perf lock contention: Show lock type with address")
> Signed-off-by: Chun-Tse Shao <ctshao@google.com>
> ---
>  tools/perf/builtin-lock.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
> index 7e36bbe3cb80..264acfa648e4 100644
> --- a/tools/perf/builtin-lock.c
> +++ b/tools/perf/builtin-lock.c
> @@ -1587,8 +1587,8 @@ static const struct {
>  	{ LCB_F_RT,			"rt-mutex",	"rt-mutex" },
>  	{ LCB_F_RT | LCB_F_READ,	"rwlock-rt:R",	"rwlock-rt" },
>  	{ LCB_F_RT | LCB_F_WRITE,	"rwlock-rt:W",	"rwlock-rt" },
> -	{ LCB_F_PERCPU | LCB_F_READ,	"pcpu-sem:R",	"percpu-rwsem" },
> -	{ LCB_F_PERCPU | LCB_F_WRITE,	"pcpu-sem:W",	"percpu-rwsem" },
> +	{ LCB_F_PERCPU | LCB_F_READ,	"pcpu-sem:R",	"pcpu-sem" },
> +	{ LCB_F_PERCPU | LCB_F_WRITE,	"pcpu-sem:W",	"pcpu-sem" },

It'll change the output of perf lock con -l.


>  	{ LCB_F_MUTEX,			"mutex",	"mutex" },
>  	{ LCB_F_MUTEX | LCB_F_SPIN,	"mutex",	"mutex" },
>  };
> @@ -2365,7 +2365,11 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
>  		/*
>  		 * Otherwise `tok` is `name` in `lock_type_table`.
>  		 * Single lock name could contain multiple flags.
> +		 * By documentation, `percpu-rwmem` should be `pcpu-sem`.
> +		 * For backward compatibility, we replace `percpu-rwmem` with `pcpu-sem`.
>  		 */
> +		if (!strcmp(tok, "percpu-rwsem"))
> +			tok = (char *)"pcpu-sem";

I think you can do this in the other way around.

Thanks,
Namhyung


>  		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)) {
> -- 
> 2.47.0.338.g60cca15819-goog
> 

Re: [PATCH v4 2/3] perf lock: Fix the wrong name percpu-rwsem

[Chun-Tse Shao]

Thank you Namhyung! Please check my v5 patchset:
https://lore.kernel.org/all/20241210200847.1023139-1-ctshao@google.com/T/#t

On Mon, Dec 9, 2024 at 2:44 PM Namhyung Kim <namhyung@kernel.org> wrote:
>
> On Mon, Dec 09, 2024 at 12:01:01PM -0800, Chun-Tse Shao wrote:
> > In `perf lock --help`, the name of `percpu-rwsem` should be
> > `pcpu-rwsem`. This patch fixes the naming in `lock_type_table`, and also
> > replaces the mismatched name `percpu-rwsem` before parsing it for
> > backward compatibility.
> >
> > Tested `./perf lock con -ab -Y pcpu-sem` and `./perf lock con -ab -Y
> > percpu-rwsem`
> >
> > Fixes: 4f701063bfa2 ("perf lock contention: Show lock type with address")
> > Signed-off-by: Chun-Tse Shao <ctshao@google.com>
> > ---
> >  tools/perf/builtin-lock.c | 8 ++++++--
> >  1 file changed, 6 insertions(+), 2 deletions(-)
> >
> > diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
> > index 7e36bbe3cb80..264acfa648e4 100644
> > --- a/tools/perf/builtin-lock.c
> > +++ b/tools/perf/builtin-lock.c
> > @@ -1587,8 +1587,8 @@ static const struct {
> >       { LCB_F_RT,                     "rt-mutex",     "rt-mutex" },
> >       { LCB_F_RT | LCB_F_READ,        "rwlock-rt:R",  "rwlock-rt" },
> >       { LCB_F_RT | LCB_F_WRITE,       "rwlock-rt:W",  "rwlock-rt" },
> > -     { LCB_F_PERCPU | LCB_F_READ,    "pcpu-sem:R",   "percpu-rwsem" },
> > -     { LCB_F_PERCPU | LCB_F_WRITE,   "pcpu-sem:W",   "percpu-rwsem" },
> > +     { LCB_F_PERCPU | LCB_F_READ,    "pcpu-sem:R",   "pcpu-sem" },
> > +     { LCB_F_PERCPU | LCB_F_WRITE,   "pcpu-sem:W",   "pcpu-sem" },
>
> It'll change the output of perf lock con -l.
>
>
> >       { LCB_F_MUTEX,                  "mutex",        "mutex" },
> >       { LCB_F_MUTEX | LCB_F_SPIN,     "mutex",        "mutex" },
> >  };
> > @@ -2365,7 +2365,11 @@ static int parse_lock_type(const struct option *opt __maybe_unused, const char *
> >               /*
> >                * Otherwise `tok` is `name` in `lock_type_table`.
> >                * Single lock name could contain multiple flags.
> > +              * By documentation, `percpu-rwmem` should be `pcpu-sem`.
> > +              * For backward compatibility, we replace `percpu-rwmem` with `pcpu-sem`.
> >                */
> > +             if (!strcmp(tok, "percpu-rwsem"))
> > +                     tok = (char *)"pcpu-sem";
>
> I think you can do this in the other way around.
>
> Thanks,
> Namhyung
>
>
> >               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)) {
> > --
> > 2.47.0.338.g60cca15819-goog
> >