bpf, perf: split bpf_perf_event_output

Split the bpf_perf_event_output() helper as a preparation into
two parts. The new bpf_perf_event_output() will prepare the raw
record itself and test for unknown flags from BPF trace context,
where the __bpf_perf_event_output() does the core work. The
latter will be reused later on from bpf_event_output() directly.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Borkmann 2016-07-14 18:08:04 +02:00 committed by David S. Miller
parent 7e3f977edd
commit 8e7a3920ac

View File

@ -233,26 +233,17 @@ static const struct bpf_func_proto bpf_perf_event_read_proto = {
.arg2_type = ARG_ANYTHING,
};
static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size)
static __always_inline u64
__bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
u64 flags, struct perf_raw_record *raw)
{
struct pt_regs *regs = (struct pt_regs *) (long) r1;
struct bpf_map *map = (struct bpf_map *) (long) r2;
struct bpf_array *array = container_of(map, struct bpf_array, map);
unsigned int cpu = smp_processor_id();
u64 index = flags & BPF_F_INDEX_MASK;
void *data = (void *) (long) r4;
struct perf_sample_data sample_data;
struct bpf_event_entry *ee;
struct perf_event *event;
struct perf_raw_record raw = {
.frag = {
.size = size,
.data = data,
},
};
if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
return -EINVAL;
if (index == BPF_F_CURRENT_CPU)
index = cpu;
if (unlikely(index >= array->map.max_entries))
@ -271,11 +262,29 @@ static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size)
return -EOPNOTSUPP;
perf_sample_data_init(&sample_data, 0, 0);
sample_data.raw = &raw;
sample_data.raw = raw;
perf_event_output(event, &sample_data, regs);
return 0;
}
static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size)
{
struct pt_regs *regs = (struct pt_regs *)(long) r1;
struct bpf_map *map = (struct bpf_map *)(long) r2;
void *data = (void *)(long) r4;
struct perf_raw_record raw = {
.frag = {
.size = size,
.data = data,
},
};
if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
return -EINVAL;
return __bpf_perf_event_output(regs, map, flags, &raw);
}
static const struct bpf_func_proto bpf_perf_event_output_proto = {
.func = bpf_perf_event_output,
.gpl_only = true,