summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/jump_label.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/include/asm/jump_label.h')
-rw-r--r--arch/x86/include/asm/jump_label.h91
1 files changed, 29 insertions, 62 deletions
diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
index 06c3cc22a058..05b16299588d 100644
--- a/arch/x86/include/asm/jump_label.h
+++ b/arch/x86/include/asm/jump_label.h
@@ -4,31 +4,37 @@
#define HAVE_JUMP_LABEL_BATCH
-#define JUMP_LABEL_NOP_SIZE 5
-
-#ifdef CONFIG_X86_64
-# define STATIC_KEY_INIT_NOP P6_NOP5_ATOMIC
-#else
-# define STATIC_KEY_INIT_NOP GENERIC_NOP5_ATOMIC
-#endif
-
#include <asm/asm.h>
#include <asm/nops.h>
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
#include <linux/stringify.h>
#include <linux/types.h>
-static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
+#define JUMP_TABLE_ENTRY(key, label) \
+ ".pushsection __jump_table, \"aw\" \n\t" \
+ _ASM_ALIGN "\n\t" \
+ ANNOTATE_DATA_SPECIAL "\n" \
+ ".long 1b - . \n\t" \
+ ".long " label " - . \n\t" \
+ _ASM_PTR " " key " - . \n\t" \
+ ".popsection \n\t"
+
+/* This macro is also expanded on the Rust side. */
+#ifdef CONFIG_HAVE_JUMP_LABEL_HACK
+#define ARCH_STATIC_BRANCH_ASM(key, label) \
+ "1: jmp " label " # objtool NOPs this \n\t" \
+ JUMP_TABLE_ENTRY(key " + 2", label)
+#else /* !CONFIG_HAVE_JUMP_LABEL_HACK */
+#define ARCH_STATIC_BRANCH_ASM(key, label) \
+ "1: .byte " __stringify(BYTES_NOP5) "\n\t" \
+ JUMP_TABLE_ENTRY(key, label)
+#endif /* CONFIG_HAVE_JUMP_LABEL_HACK */
+
+static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch)
{
- asm_volatile_goto("1:"
- ".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t"
- ".pushsection __jump_table, \"aw\" \n\t"
- _ASM_ALIGN "\n\t"
- ".long 1b - ., %l[l_yes] - . \n\t"
- _ASM_PTR "%c0 + %c1 - .\n\t"
- ".popsection \n\t"
+ asm goto(ARCH_STATIC_BRANCH_ASM("%c0 + %c1", "%l[l_yes]")
: : "i" (key), "i" (branch) : : l_yes);
return false;
@@ -36,16 +42,11 @@ l_yes:
return true;
}
-static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
+static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch)
{
- asm_volatile_goto("1:"
- ".byte 0xe9\n\t .long %l[l_yes] - 2f\n\t"
- "2:\n\t"
- ".pushsection __jump_table, \"aw\" \n\t"
- _ASM_ALIGN "\n\t"
- ".long 1b - ., %l[l_yes] - . \n\t"
- _ASM_PTR "%c0 + %c1 - .\n\t"
- ".popsection \n\t"
+ asm goto("1:"
+ "jmp %l[l_yes]\n\t"
+ JUMP_TABLE_ENTRY("%c0 + %c1", "%l[l_yes]")
: : "i" (key), "i" (branch) : : l_yes);
return false;
@@ -53,42 +54,8 @@ l_yes:
return true;
}
-#else /* __ASSEMBLY__ */
-
-.macro STATIC_JUMP_IF_TRUE target, key, def
-.Lstatic_jump_\@:
- .if \def
- /* Equivalent to "jmp.d32 \target" */
- .byte 0xe9
- .long \target - .Lstatic_jump_after_\@
-.Lstatic_jump_after_\@:
- .else
- .byte STATIC_KEY_INIT_NOP
- .endif
- .pushsection __jump_table, "aw"
- _ASM_ALIGN
- .long .Lstatic_jump_\@ - ., \target - .
- _ASM_PTR \key - .
- .popsection
-.endm
-
-.macro STATIC_JUMP_IF_FALSE target, key, def
-.Lstatic_jump_\@:
- .if \def
- .byte STATIC_KEY_INIT_NOP
- .else
- /* Equivalent to "jmp.d32 \target" */
- .byte 0xe9
- .long \target - .Lstatic_jump_after_\@
-.Lstatic_jump_after_\@:
- .endif
- .pushsection __jump_table, "aw"
- _ASM_ALIGN
- .long .Lstatic_jump_\@ - ., \target - .
- _ASM_PTR \key + 1 - .
- .popsection
-.endm
+extern int arch_jump_entry_size(struct jump_entry *entry);
-#endif /* __ASSEMBLY__ */
+#endif /* __ASSEMBLER__ */
#endif