mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-19 18:24:14 +08:00
ef64789413
The linker should not be adding holes to word size aligned pointers, but out of paranoia we are explicitly specifying that alignment. I have not seen any holes in the jump label section in practice. Signed-off-by: Jason Baron <jbaron@redhat.com> LKML-Reference: <e119fbd060c9452c56063ea6148ba1070e7434cc.1300299760.git.jbaron@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
43 lines
753 B
C
43 lines
753 B
C
#ifndef _ASM_X86_JUMP_LABEL_H
|
|
#define _ASM_X86_JUMP_LABEL_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/types.h>
|
|
#include <asm/nops.h>
|
|
#include <asm/asm.h>
|
|
|
|
#define JUMP_LABEL_NOP_SIZE 5
|
|
|
|
#define JUMP_LABEL_INITIAL_NOP ".byte 0xe9 \n\t .long 0\n\t"
|
|
|
|
static __always_inline bool arch_static_branch(struct jump_label_key *key)
|
|
{
|
|
asm goto("1:"
|
|
JUMP_LABEL_INITIAL_NOP
|
|
".pushsection __jump_table, \"aw\" \n\t"
|
|
_ASM_ALIGN "\n\t"
|
|
_ASM_PTR "1b, %l[l_yes], %c0 \n\t"
|
|
".popsection \n\t"
|
|
: : "i" (key) : : l_yes);
|
|
return false;
|
|
l_yes:
|
|
return true;
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#ifdef CONFIG_X86_64
|
|
typedef u64 jump_label_t;
|
|
#else
|
|
typedef u32 jump_label_t;
|
|
#endif
|
|
|
|
struct jump_entry {
|
|
jump_label_t code;
|
|
jump_label_t target;
|
|
jump_label_t key;
|
|
};
|
|
|
|
#endif
|