@@ -157,7 +157,8 @@ CONTENTION OPTIONS
-M::
--map-nr-entries=<value>::
- Maximum number of BPF map entries (default: 10240).
+ Maximum number of BPF map entries (default: 16384).
+ This will be aligned to a power of 2.
--max-stack=<value>::
Maximum stack depth when collecting lock contention (default: 8).
@@ -60,7 +60,7 @@ static bool show_thread_stats;
static bool show_lock_addrs;
static bool show_lock_owner;
static bool use_bpf;
-static unsigned long bpf_map_entries = 10240;
+static unsigned long bpf_map_entries = MAX_ENTRIES;
static int max_stack_depth = CONTENTION_STACK_DEPTH;
static int stack_skip = CONTENTION_STACK_SKIP;
static int print_nr_entries = INT_MAX / 2;
@@ -7,9 +7,6 @@
#include "lock_data.h"
-/* default buffer size */
-#define MAX_ENTRIES 10240
-
/* for collect_lock_syms(). 4096 was rejected by the verifier */
#define MAX_CPUS 1024
@@ -63,7 +60,7 @@ struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(key_size, sizeof(__u64));
__uint(value_size, sizeof(__u32));
- __uint(max_entries, 16384);
+ __uint(max_entries, MAX_ENTRIES);
} lock_syms SEC(".maps");
struct {
@@ -15,6 +15,9 @@ struct contention_task_data {
char comm[TASK_COMM_LEN];
};
+/* default buffer size */
+#define MAX_ENTRIES 16384
+
/*
* Upper bits of the flags in the contention_data are used to identify
* some well-known locks which do not have symbols (non-global locks).
The BPF hash map will align the map size to a power of 2. So 10k would be 16k anyway. Let's have the actual size to avoid confusions. Signed-off-by: Namhyung Kim <namhyung@kernel.org> --- tools/perf/Documentation/perf-lock.txt | 3 ++- tools/perf/builtin-lock.c | 2 +- tools/perf/util/bpf_skel/lock_contention.bpf.c | 5 +---- tools/perf/util/bpf_skel/lock_data.h | 3 +++ 4 files changed, 7 insertions(+), 6 deletions(-)