Commit 3124591f authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

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: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-6-andrii@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent b4ccf915

include/trace/events/bpf_test_run.h

+17 −0
Original line number Diff line number Diff line
@@ -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),

kernel/bpf/helpers.c

+1 −0
Original line number Diff line number Diff line
@@ -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 = {

net/bpf/test_run.c

+8 −0
Original line number Diff line number Diff line
@@ -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)