[PATCH 1/4] perf lock contention: Add lock_data.h for common data

From: Namhyung Kim
Date: Fri Dec 09 2022 - 14:07:43 EST


Accessing BPF maps should use the same data types. Add bpf_skel/lock_data.h
to define the common data structures. No functional changes.

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/bpf_lock_contention.c | 19 ++++--------
.../perf/util/bpf_skel/lock_contention.bpf.c | 17 ++---------
tools/perf/util/bpf_skel/lock_data.h | 30 +++++++++++++++++++
3 files changed, 38 insertions(+), 28 deletions(-)
create mode 100644 tools/perf/util/bpf_skel/lock_data.h

diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c
index f4ebb9a2e380..b6a8eb7164b3 100644
--- a/tools/perf/util/bpf_lock_contention.c
+++ b/tools/perf/util/bpf_lock_contention.c
@@ -12,17 +12,10 @@
#include <bpf/bpf.h>

#include "bpf_skel/lock_contention.skel.h"
+#include "bpf_skel/lock_data.h"

static struct lock_contention_bpf *skel;

-struct lock_contention_data {
- u64 total_time;
- u64 min_time;
- u64 max_time;
- u32 count;
- u32 flags;
-};
-
int lock_contention_prepare(struct lock_contention *con)
{
int i, fd;
@@ -110,8 +103,8 @@ int lock_contention_stop(void)
int lock_contention_read(struct lock_contention *con)
{
int fd, stack, err = 0;
- s32 prev_key, key;
- struct lock_contention_data data = {};
+ struct contention_key *prev_key, key;
+ struct contention_data data = {};
struct lock_stat *st = NULL;
struct machine *machine = con->machine;
u64 *stack_trace;
@@ -126,8 +119,8 @@ int lock_contention_read(struct lock_contention *con)
if (stack_trace == NULL)
return -1;

- prev_key = 0;
- while (!bpf_map_get_next_key(fd, &prev_key, &key)) {
+ prev_key = NULL;
+ while (!bpf_map_get_next_key(fd, prev_key, &key)) {
struct map *kmap;
struct symbol *sym;
int idx = 0;
@@ -184,7 +177,7 @@ int lock_contention_read(struct lock_contention *con)
}

hlist_add_head(&st->hash_entry, con->result);
- prev_key = key;
+ prev_key = &key;

/* we're fine now, reset the values */
st = NULL;
diff --git a/tools/perf/util/bpf_skel/lock_contention.bpf.c b/tools/perf/util/bpf_skel/lock_contention.bpf.c
index 9681cb59b0df..0f63cc28ccba 100644
--- a/tools/perf/util/bpf_skel/lock_contention.bpf.c
+++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c
@@ -5,24 +5,11 @@
#include <bpf/bpf_tracing.h>
#include <bpf/bpf_core_read.h>

-/* maximum stack trace depth */
-#define MAX_STACKS 8
+#include "lock_data.h"

/* default buffer size */
#define MAX_ENTRIES 10240

-struct contention_key {
- __s32 stack_id;
-};
-
-struct contention_data {
- __u64 total_time;
- __u64 min_time;
- __u64 max_time;
- __u32 count;
- __u32 flags;
-};
-
struct tstamp_data {
__u64 timestamp;
__u64 lock;
@@ -34,7 +21,7 @@ struct tstamp_data {
struct {
__uint(type, BPF_MAP_TYPE_STACK_TRACE);
__uint(key_size, sizeof(__u32));
- __uint(value_size, MAX_STACKS * sizeof(__u64));
+ __uint(value_size, sizeof(__u64));
__uint(max_entries, MAX_ENTRIES);
} stacks SEC(".maps");

diff --git a/tools/perf/util/bpf_skel/lock_data.h b/tools/perf/util/bpf_skel/lock_data.h
new file mode 100644
index 000000000000..dbdf4caedc4a
--- /dev/null
+++ b/tools/perf/util/bpf_skel/lock_data.h
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Data structures shared between BPF and tools. */
+#ifndef UTIL_BPF_SKEL_LOCK_DATA_H
+#define UTIL_BPF_SKEL_LOCK_DATA_H
+
+struct contention_key {
+ s32 stack_or_task_id;
+};
+
+#define TASK_COMM_LEN 16
+
+struct contention_task_data {
+ char comm[TASK_COMM_LEN];
+};
+
+struct contention_data {
+ u64 total_time;
+ u64 min_time;
+ u64 max_time;
+ u32 count;
+ u32 flags;
+};
+
+enum lock_aggr_mode {
+ LOCK_AGGR_ADDR = 0,
+ LOCK_AGGR_TASK,
+ LOCK_AGGR_CALLER,
+};
+
+#endif /* UTIL_BPF_SKEL_LOCK_DATA_H */
--
2.39.0.rc1.256.g54fd8350bd-goog