Commit 67fe4591 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

selftests/bpf: add arg:ctx cases to test_global_funcs tests 



Add a few extra cases of global funcs with context arguments. This time
rely on "arg:ctx" decl_tag (__arg_ctx macro), but put it next to
"classic" cases where context argument has to be of an exact type that
BPF verifier expects (e.g., bpf_user_pt_regs_t for kprobe/uprobe).

Colocating all these cases separately from other global func args that
rely on arg:xxx decl tags (in verifier_global_subprogs.c) allows for
simpler backwards compatibility testing on old kernels. All the cases in
test_global_func_ctx_args.c are supposed to work on older kernels, which
was manually validated during development.

Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240104013847.3875810-9-andrii@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 2f38fe68

tools/testing/selftests/bpf/progs/test_global_func_ctx_args.c

+49 −0
Original line number Diff line number Diff line
@@ -102,3 +102,52 @@ int perf_event_ctx(void *ctx) 
{

	return perf_event_ctx_subprog(ctx);

}



/* this global subprog can be now called from many types of entry progs, each

 * with different context type

 */

__weak int subprog_ctx_tag(void *ctx __arg_ctx)

{

	return bpf_get_stack(ctx, stack, sizeof(stack), 0);

}



struct my_struct { int x; };



__weak int subprog_multi_ctx_tags(void *ctx1 __arg_ctx,

				  struct my_struct *mem,

				  void *ctx2 __arg_ctx)

{

	if (!mem)

		return 0;



	return bpf_get_stack(ctx1, stack, sizeof(stack), 0) +

	       mem->x +

	       bpf_get_stack(ctx2, stack, sizeof(stack), 0);

}



SEC("?raw_tp")

__success __log_level(2)

int arg_tag_ctx_raw_tp(void *ctx)

{

	struct my_struct x = { .x = 123 };



	return subprog_ctx_tag(ctx) + subprog_multi_ctx_tags(ctx, &x, ctx);

}



SEC("?perf_event")

__success __log_level(2)

int arg_tag_ctx_perf(void *ctx)

{

	struct my_struct x = { .x = 123 };



	return subprog_ctx_tag(ctx) + subprog_multi_ctx_tags(ctx, &x, ctx);

}



SEC("?kprobe")

__success __log_level(2)

int arg_tag_ctx_kprobe(void *ctx)

{

	struct my_struct x = { .x = 123 };



	return subprog_ctx_tag(ctx) + subprog_multi_ctx_tags(ctx, &x, ctx);

}