From: Andrii Nakryiko <andriin@xxxxxx> [ Upstream commit a53ba15d81995868651dd28a85d8045aef3d4e20 ] Due to a quirky C syntax of declaring pointers to array or function prototype, existing __type() macro doesn't work with map key/value types that are array or function prototype. One has to create a typedef first and use it to specify key/value type for a BPF map. By using typeof(), pointer to type is now handled uniformly for all kinds of types. Convert one of self-tests as a demonstration. Signed-off-by: Andrii Nakryiko <andriin@xxxxxx> Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Link: https://lore.kernel.org/bpf/20191004040211.2434033-1-andriin@xxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/bpf/bpf_helpers.h | 2 +- tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c | 3 +-- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index 54a50699bbfda..9f77cbaac01c1 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -3,7 +3,7 @@ #define __BPF_HELPERS__ #define __uint(name, val) int (*name)[val] -#define __type(name, val) val *name +#define __type(name, val) typeof(val) *name /* helper macro to print out debug messages */ #define bpf_printk(fmt, ...) \ diff --git a/tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c b/tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c index f8ffa3f3d44bb..6cc4479ac9df6 100644 --- a/tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c +++ b/tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c @@ -47,12 +47,11 @@ struct { * issue and avoid complicated C programming massaging. * This is an acceptable workaround since there is one entry here. */ -typedef __u64 raw_stack_trace_t[2 * MAX_STACK_RAWTP]; struct { __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); __uint(max_entries, 1); __type(key, __u32); - __type(value, raw_stack_trace_t); + __type(value, __u64[2 * MAX_STACK_RAWTP]); } rawdata_map SEC(".maps"); SEC("raw_tracepoint/sys_enter") -- 2.20.1
