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| author |   Martin KaFai Lau <kafai@fb.com> | 2020-11-12 13:13:13 -0800 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2020-11-12 18:39:28 -0800 |
| commit | 8e4597c627fb48f361e2a5b012202cb1b6cbcd5e (patch) | |
| tree | feab62b4fd4006ab7d2536ec40b8aa923506eb9e /kernel | |
| parent | bpf: Rename some functions in bpf_sk_storage (diff) | |
| download | linux-dev-8e4597c627fb48f361e2a5b012202cb1b6cbcd5e.tar.xz linux-dev-8e4597c627fb48f361e2a5b012202cb1b6cbcd5e.zip | |
bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP
This patch enables the FENTRY/FEXIT/RAW_TP tracing program to use
the bpf_sk_storage_(get|delete) helper, so those tracing programs
can access the sk's bpf_local_storage and the later selftest
will show some examples.
The bpf_sk_storage is currently used in bpf-tcp-cc, tc,
cg sockops...etc which is running either in softirq or
task context.
This patch adds bpf_sk_storage_get_tracing_proto and
bpf_sk_storage_delete_tracing_proto. They will check
in runtime that the helpers can only be called when serving
softirq or running in a task context. That should enable
most common tracing use cases on sk.
During the load time, the new tracing_allowed() function
will ensure the tracing prog using the bpf_sk_storage_(get|delete)
helper is not tracing any bpf_sk_storage*() function itself.
The sk is passed as "void *" when calling into bpf_local_storage.
This patch only allows tracing a kernel function.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201112211313.2587383-1-kafai@fb.com
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index e4515b0f62a8..cfce60ad1cb5 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -16,6 +16,7 @@ #include <linux/syscalls.h> #include <linux/error-injection.h> #include <linux/btf_ids.h> +#include <net/bpf_sk_storage.h> #include <uapi/linux/bpf.h> #include <uapi/linux/btf.h> @@ -1735,6 +1736,10 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_skc_to_tcp_request_sock_proto; case BPF_FUNC_skc_to_udp6_sock: return &bpf_skc_to_udp6_sock_proto; + case BPF_FUNC_sk_storage_get: + return &bpf_sk_storage_get_tracing_proto; + case BPF_FUNC_sk_storage_delete: + return &bpf_sk_storage_delete_tracing_proto; #endif case BPF_FUNC_seq_printf: return prog->expected_attach_type == BPF_TRACE_ITER ? |