[PATCH v5 net-next 21/29] tracing: allow eBPF programs to call ktime_get_ns() and get_current()
From: Alexei Starovoitov <hidden>
Date: 2014-08-24 20:25:51
Also in:
linux-api, lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [security & lsm] (security audit and enforcement using bpf), bpf [tracing], the rest, tracing · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, KP Singh, Matt Bobrowski, Song Liu, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Signed-off-by: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org> --- include/uapi/linux/bpf.h | 2 ++ kernel/trace/bpf_trace.c | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 5adaad826471..e866a2fcba8b 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h@@ -416,6 +416,8 @@ enum bpf_func_id { BPF_FUNC_memcmp, /* int bpf_memcmp(void *unsafe_ptr, void *safe_ptr, int size) */ BPF_FUNC_dump_stack, /* void bpf_dump_stack(void) */ BPF_FUNC_printk, /* int bpf_printk(const char *fmt, int fmt_size, ...) */ + BPF_FUNC_ktime_get_ns, /* u64 bpf_ktime_get_ns(void) */ + BPF_FUNC_get_current, /* struct task_struct *bpf_get_current(void) */ __BPF_FUNC_MAX_ID, };
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index ff98be5a24d6..a98e13e1131b 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c@@ -114,6 +114,16 @@ static u64 bpf_printk(u64 r1, u64 fmt_size, u64 r3, u64 r4, u64 r5) mod_l[2] ? r5 : (u32) r5); } +static u64 bpf_ktime_get_ns(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + return ktime_get_ns(); +} + +static u64 bpf_get_current(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + return (u64) (long) current; +} + static struct bpf_func_proto tracing_filter_funcs[] = { #define FETCH(SIZE) \ [BPF_FUNC_fetch_##SIZE] = { \
@@ -169,6 +179,16 @@ static struct bpf_func_proto tracing_filter_funcs[] = { .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, }, + [BPF_FUNC_ktime_get_ns] = { + .func = bpf_ktime_get_ns, + .gpl_only = true, + .ret_type = RET_INTEGER, + }, + [BPF_FUNC_get_current] = { + .func = bpf_get_current, + .gpl_only = true, + .ret_type = RET_INTEGER, + }, }; static const struct bpf_func_proto *tracing_filter_func_proto(enum bpf_func_id func_id)
--
1.7.9.5