From: Eduard Zingerman Date: Sat, 21 Jan 2023 00:22:37 +0000 (+0530) Subject: selftests/bpf: convenience macro for use with 'asm volatile' blocks X-Git-Tag: v6.3-rc1~162^2~189^2~16^2~4 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=91b875a5e43b3a8dec4fbdca067c8860004b5f0e;p=tomoyo%2Ftomoyo-test1.git selftests/bpf: convenience macro for use with 'asm volatile' blocks A set of macros useful for writing naked BPF functions using inline assembly. E.g. as follows: struct map_struct { ... } map SEC(".maps"); SEC(...) __naked int foo_test(void) { asm volatile( "r0 = 0;" "*(u64*)(r10 - 8) = r0;" "r1 = %[map] ll;" "r2 = r10;" "r2 += -8;" "call %[bpf_map_lookup_elem];" "r0 = 0;" "exit;" : : __imm(bpf_map_lookup_elem), __imm_addr(map) : __clobber_all); } Acked-by: Andrii Nakryiko Acked-by: Yonghong Song Signed-off-by: Eduard Zingerman [ Kartikeya: Add acks, include __clobber_common from Andrii ] Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20230121002241.2113993-9-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- diff --git a/tools/testing/selftests/bpf/progs/bpf_misc.h b/tools/testing/selftests/bpf/progs/bpf_misc.h index 4a01ea9113bf..2d7b89b447b2 100644 --- a/tools/testing/selftests/bpf/progs/bpf_misc.h +++ b/tools/testing/selftests/bpf/progs/bpf_misc.h @@ -7,6 +7,13 @@ #define __success __attribute__((btf_decl_tag("comment:test_expect_success"))) #define __log_level(lvl) __attribute__((btf_decl_tag("comment:test_log_level="#lvl))) +/* Convenience macro for use with 'asm volatile' blocks */ +#define __naked __attribute__((naked)) +#define __clobber_all "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "memory" +#define __clobber_common "r0", "r1", "r2", "r3", "r4", "r5", "memory" +#define __imm(name) [name]"i"(name) +#define __imm_addr(name) [name]"i"(&name) + #if defined(__TARGET_ARCH_x86) #define SYSCALL_WRAPPER 1 #define SYS_PREFIX "__x64_"