bpf: add bpf_modify_return_test_tp() kfunc triggering tracepoint

Add a simple bpf_modify_return_test_tp() kfunc, available to all program
types, that is useful for various testing and benchmarking scenarios, as
it allows to trigger most tracing BPF program types from BPF side,
allowing to do complex testing and benchmarking scenarios.

It is also attachable to for fmod_ret programs, making it a good and
simple way to trigger fmod_ret program under test/benchmark.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Andrii Nakryiko 2024-03-26 09:21:50 -07:00 committed by Alexei Starovoitov
parent b4ccf9158f
commit 3124591f68
3 changed files with 26 additions and 0 deletions

View File

@ -7,6 +7,23 @@
#include <linux/tracepoint.h>
TRACE_EVENT(bpf_trigger_tp,
TP_PROTO(int nonce),
TP_ARGS(nonce),
TP_STRUCT__entry(
__field(int, nonce)
),
TP_fast_assign(
__entry->nonce = nonce;
),
TP_printk("nonce %d", __entry->nonce)
);
DECLARE_EVENT_CLASS(bpf_test_finish,
TP_PROTO(int *err),

View File

@ -2625,6 +2625,7 @@ BTF_ID_FLAGS(func, bpf_dynptr_is_null)
BTF_ID_FLAGS(func, bpf_dynptr_is_rdonly)
BTF_ID_FLAGS(func, bpf_dynptr_size)
BTF_ID_FLAGS(func, bpf_dynptr_clone)
BTF_ID_FLAGS(func, bpf_modify_return_test_tp)
BTF_KFUNCS_END(common_btf_ids)
static const struct btf_kfunc_id_set common_kfunc_set = {

View File

@ -575,6 +575,13 @@ __bpf_kfunc int bpf_modify_return_test2(int a, int *b, short c, int d,
return a + *b + c + d + (long)e + f + g;
}
__bpf_kfunc int bpf_modify_return_test_tp(int nonce)
{
trace_bpf_trigger_tp(nonce);
return nonce;
}
int noinline bpf_fentry_shadow_test(int a)
{
return a + 1;
@ -622,6 +629,7 @@ __bpf_kfunc_end_defs();
BTF_KFUNCS_START(bpf_test_modify_return_ids)
BTF_ID_FLAGS(func, bpf_modify_return_test)
BTF_ID_FLAGS(func, bpf_modify_return_test2)
BTF_ID_FLAGS(func, bpf_modify_return_test_tp)
BTF_ID_FLAGS(func, bpf_fentry_test1, KF_SLEEPABLE)
BTF_KFUNCS_END(bpf_test_modify_return_ids)