linux_dsm_epyc7002/arch/s390/include/asm/jump_label.h
Jan Glauber 5373db886b jump label: Add s390 support
Implement the architecture backend for jump label support on s390.

For a shared kernel booted from a NSS silently disable jump labels
because the NSS is read-only. Therefore jump labels will be disabled
in a shared kernel and can't be activated.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
LKML-Reference: <6935d2c41ce111e1719176ed4bbd3dbe4de80855.1300299760.git.jbaron@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-04-04 13:43:16 -04:00

38 lines
669 B
C

#ifndef _ASM_S390_JUMP_LABEL_H
#define _ASM_S390_JUMP_LABEL_H
#include <linux/types.h>
#define JUMP_LABEL_NOP_SIZE 6
#ifdef CONFIG_64BIT
#define ASM_PTR ".quad"
#define ASM_ALIGN ".balign 8"
#else
#define ASM_PTR ".long"
#define ASM_ALIGN ".balign 4"
#endif
static __always_inline bool arch_static_branch(struct jump_label_key *key)
{
asm goto("0: brcl 0,0\n"
".pushsection __jump_table, \"aw\"\n"
ASM_ALIGN "\n"
ASM_PTR " 0b, %l[label], %0\n"
".popsection\n"
: : "X" (key) : : label);
return false;
label:
return true;
}
typedef unsigned long jump_label_t;
struct jump_entry {
jump_label_t code;
jump_label_t target;
jump_label_t key;
};
#endif