Messages in this thread Patch in this message | | | From | Kaixu Xia <> | Subject | [PATCH V3 2/2] bpf: control all the perf events stored in PERF_EVENT_ARRAY maps | Date | Fri, 16 Oct 2015 07:42:13 +0000 |
| |
This patch implements the function that controlling all the perf events stored in PERF_EVENT_ARRAY maps by setting the parameter 'index' to maps max_entries.
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com> --- kernel/trace/bpf_trace.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 3175600..4b385863 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -229,13 +229,30 @@ static u64 bpf_perf_event_dump_control(u64 r1, u64 index, u64 flag, u64 r4, u64 struct bpf_map *map = (struct bpf_map *) (unsigned long) r1; struct bpf_array *array = container_of(map, struct bpf_array, map); struct perf_event *event; + int i; - if (unlikely(index >= array->map.max_entries)) + if (unlikely(index > array->map.max_entries)) return -E2BIG; if (flag & BIT_FLAG_CHECK) return -EINVAL; + if (index == array->map.max_entries) { + bool dump_control = flag & BIT_DUMP_CTL; + + for (i = 0; i < array->map.max_entries; i++) { + event = (struct perf_event *)array->ptrs[i]; + if (!event) + continue; + + if (dump_control) + atomic_dec_if_positive(&event->dump_enable); + else + atomic_inc_unless_negative(&event->dump_enable); + } + return 0; + } + event = (struct perf_event *)array->ptrs[index]; if (!event) return -ENOENT; @@ -244,7 +261,6 @@ static u64 bpf_perf_event_dump_control(u64 r1, u64 index, u64 flag, u64 r4, u64 atomic_dec_if_positive(&event->dump_enable); else atomic_inc_unless_negative(&event->dump_enable); - return 0; } -- 1.8.3.4
| |