diff options
Diffstat (limited to 'tools/lib/bpf/bpf_helpers.h')
| -rw-r--r-- | tools/lib/bpf/bpf_helpers.h | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index cc2e51c64a54..9720dc0b4605 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -25,9 +25,16 @@ /* * Helper macro to place programs, maps, license in * different sections in elf_bpf file. Section names - * are interpreted by elf_bpf loader + * are interpreted by libbpf depending on the context (BPF programs, BPF maps, + * extern variables, etc). + * To allow use of SEC() with externs (e.g., for extern .maps declarations), + * make sure __attribute__((unused)) doesn't trigger compilation warning. */ -#define SEC(NAME) __attribute__((section(NAME), used)) +#define SEC(name) \ + _Pragma("GCC diagnostic push") \ + _Pragma("GCC diagnostic ignored \"-Wignored-attributes\"") \ + __attribute__((section(name), used)) \ + _Pragma("GCC diagnostic pop") \ /* Avoid 'linux/stddef.h' definition of '__always_inline'. */ #undef __always_inline @@ -40,6 +47,14 @@ #define __weak __attribute__((weak)) #endif +/* + * Use __hidden attribute to mark a non-static BPF subprogram effectively + * static for BPF verifier's verification algorithm purposes, allowing more + * extensive and permissive BPF verification process, taking into account + * subprogram's caller context. + */ +#define __hidden __attribute__((visibility("hidden"))) + /* When utilizing vmlinux.h with BPF CO-RE, user BPF programs can't include * any system-level headers (such as stddef.h, linux/version.h, etc), and * commonly-used macros like NULL and KERNEL_VERSION aren't available through @@ -51,7 +66,7 @@ #endif #ifndef KERNEL_VERSION -#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + ((c) > 255 ? 255 : (c)) +#define KERNEL_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + ((c) > 255 ? 255 : (c))) #endif /* |