The functions bpf_perf_event_sample_enable/disable() can set the
flag sample_disable to enable/disable output trace data on samples.
Signed-off-by: Kaixu Xia <xiaka...@huawei.com>
---
include/linux/bpf.h | 2 ++
include/uapi/linux/bpf.h | 2 ++
kernel/bpf/verifier.c | 4 +++-
kernel/trace/bpf_trace.c | 34 ++++++++++++++++++++++++++++++++++
4 files changed, 41 insertions(+), 1 deletion(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 25e073d..09148ff 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -192,6 +192,8 @@ extern const struct bpf_func_proto
bpf_map_update_elem_proto;
extern const struct bpf_func_proto bpf_map_delete_elem_proto;
extern const struct bpf_func_proto bpf_perf_event_read_proto;
+extern const struct bpf_func_proto bpf_perf_event_sample_enable_proto;
+extern const struct bpf_func_proto bpf_perf_event_sample_disable_proto;
extern const struct bpf_func_proto bpf_get_prandom_u32_proto;
extern const struct bpf_func_proto bpf_get_smp_processor_id_proto;
extern const struct bpf_func_proto bpf_tail_call_proto;
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 92a48e2..5229c550 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -272,6 +272,8 @@ enum bpf_func_id {
BPF_FUNC_skb_get_tunnel_key,
BPF_FUNC_skb_set_tunnel_key,
BPF_FUNC_perf_event_read, /* u64 bpf_perf_event_read(&map, index)
*/
+ BPF_FUNC_perf_event_sample_enable, /* u64
bpf_perf_event_enable(&map) */
+ BPF_FUNC_perf_event_sample_disable, /* u64
bpf_perf_event_disable(&map) */
__BPF_FUNC_MAX_ID,
};
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b074b23..6428daf 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -244,6 +244,8 @@ static const struct {
} func_limit[] = {
{BPF_MAP_TYPE_PROG_ARRAY, BPF_FUNC_tail_call},
{BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_read},
+ {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_sample_enable},
+ {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_sample_disable},
};
static void print_verifier_state(struct verifier_env *env)
@@ -860,7 +862,7 @@ static int check_map_func_compatibility(struct bpf_map
*map, int func_id)
* don't allow any other map type to be passed into
* the special func;
*/
- if (bool_map != bool_func)
+ if (bool_func && bool_map != bool_func)
return -EINVAL;
}
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 0fe96c7..abe943a 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -215,6 +215,36 @@ const struct bpf_func_proto bpf_perf_event_read_proto = {
.arg2_type = ARG_ANYTHING,
};
+static u64 bpf_perf_event_sample_enable(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+
+ atomic_set(&map->perf_sample_disable, 0);
+ return 0;
+}
+
+const struct bpf_func_proto bpf_perf_event_sample_enable_proto = {
+ .func = bpf_perf_event_sample_enable,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+};
+
+static u64 bpf_perf_event_sample_disable(u64 r1, u64 r2, u64 r3, u64 r4, u64
r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+
+ atomic_set(&map->perf_sample_disable, 1);
+ return 0;
+}
+
+const struct bpf_func_proto bpf_perf_event_sample_disable_proto = {
+ .func = bpf_perf_event_sample_disable,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+};
+
static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id
func_id)
{
switch (func_id) {
@@ -242,6 +272,10 @@ static const struct bpf_func_proto
*kprobe_prog_func_proto(enum bpf_func_id func
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_perf_event_read:
return &bpf_perf_event_read_proto;
+ case BPF_FUNC_perf_event_sample_enable:
+ return &bpf_perf_event_sample_enable_proto;
+ case BPF_FUNC_perf_event_sample_disable:
+ return &bpf_perf_event_sample_disable_proto;
default:
return NULL;
}
--
1.8.3.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
