bpf, x64: clean up retpoline emission slightly

Make the RETPOLINE_{RA,ED}X_BPF_JIT() a bit more readable by
cleaning up the macro, aligning comments and spacing.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 2cd344d1a6e5a653e4099d7bc4f4bc9a47fe4390..2f700a1db851ea3ad907a81a8b595dcba213d773 100644 (file)
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -301,9 +301,9 @@ do {                                                                        \
  *    jmp *%edx for x86_32
  */
 #ifdef CONFIG_RETPOLINE
-#ifdef CONFIG_X86_64
-# define RETPOLINE_RAX_BPF_JIT_SIZE    17
-# define RETPOLINE_RAX_BPF_JIT()                               \
+# ifdef CONFIG_X86_64
+#  define RETPOLINE_RAX_BPF_JIT_SIZE   17
+#  define RETPOLINE_RAX_BPF_JIT()                              \
 do {                                                           \
        EMIT1_off32(0xE8, 7);    /* callq do_rop */             \
        /* spec_trap: */                                        \
@@ -314,8 +314,8 @@ do {                                                                \
        EMIT4(0x48, 0x89, 0x04, 0x24); /* mov %rax,(%rsp) */    \
        EMIT1(0xC3);             /* retq */                     \
 } while (0)
-#else
-# define RETPOLINE_EDX_BPF_JIT()                               \
+# else /* !CONFIG_X86_64 */
+#  define RETPOLINE_EDX_BPF_JIT()                              \
 do {                                                           \
        EMIT1_off32(0xE8, 7);    /* call do_rop */              \
        /* spec_trap: */                                        \
@@ -326,17 +326,16 @@ do {                                                              \
        EMIT3(0x89, 0x14, 0x24); /* mov %edx,(%esp) */          \
        EMIT1(0xC3);             /* ret */                      \
 } while (0)
-#endif
+# endif
 #else /* !CONFIG_RETPOLINE */
-
-#ifdef CONFIG_X86_64
-# define RETPOLINE_RAX_BPF_JIT_SIZE    2
-# define RETPOLINE_RAX_BPF_JIT()                               \
-       EMIT2(0xFF, 0xE0);       /* jmp *%rax */
-#else
-# define RETPOLINE_EDX_BPF_JIT()                               \
-       EMIT2(0xFF, 0xE2) /* jmp *%edx */
-#endif
+# ifdef CONFIG_X86_64
+#  define RETPOLINE_RAX_BPF_JIT_SIZE   2
+#  define RETPOLINE_RAX_BPF_JIT()                              \
+       EMIT2(0xFF, 0xE0);       /* jmp *%rax */
+# else /* !CONFIG_X86_64 */
+#  define RETPOLINE_EDX_BPF_JIT()                              \
+       EMIT2(0xFF, 0xE2)        /* jmp *%edx */
+# endif
 #endif
 
 #endif /* _ASM_X86_NOSPEC_BRANCH_H_ */