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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_S390_JUMP_LABEL_H
#define _ASM_S390_JUMP_LABEL_H
#define HAVE_JUMP_LABEL_BATCH
#ifndef __ASSEMBLER__
#include <linux/types.h>
#include <linux/stringify.h>
#define JUMP_LABEL_NOP_SIZE 6
#ifdef CONFIG_CC_IS_CLANG
#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "i"
#elif __GNUC__ < 9
#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "X"
#else
#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "jdd"
#endif
#define ARCH_JUMP_TABLE_ENTRY(key, label, local_label) \
".pushsection __jump_table,\"aw\"\n" \
".balign 8\n" \
".long " local_label "-.," label "-.\n" \
".quad " key "-.\n" \
".popsection\n"
/*
* We use a brcl 0,<offset> instruction for jump labels so it
* can be easily distinguished from a hotpatch generated instruction.
*/
#define ARCH_STATIC_BRANCH_ASM(key, label) \
"0: brcl 0," label "\n" \
ARCH_JUMP_TABLE_ENTRY(key, label, "0b")
#define ARCH_STATIC_BRANCH_JUMP_ASM(key, label) \
"0: brcl 15," label "\n" \
ARCH_JUMP_TABLE_ENTRY(key, label, "0b")
static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
{
asm goto(ARCH_STATIC_BRANCH_ASM("%0+%1", "%l[label]")
: : JUMP_LABEL_STATIC_KEY_CONSTRAINT (key), "i" (branch) : : label);
return false;
label:
return true;
}
static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
{
asm goto(ARCH_STATIC_BRANCH_JUMP_ASM("%0+%1", "%l[label]")
: : JUMP_LABEL_STATIC_KEY_CONSTRAINT (key), "i" (branch) : : label);
return false;
label:
return true;
}
#endif /* __ASSEMBLER__ */
#endif
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