From 8e7a3920ac277dd4e690c0e70c9750176e3acb83 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Thu, 14 Jul 2016 18:08:04 +0200 Subject: [PATCH] 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 Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/trace/bpf_trace.c | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 35ab1b2b041b..c35883a9bc11 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -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, -- 2.20.1