s390/jump-label: add arch_jump_label_transform_static()

This allows jump-label entries to be cheaply updated on code which is
not yet live.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jan Glauber <jang@linux.vnet.ibm.com>
This commit is contained in:
Jeremy Fitzhardinge 2011-09-29 10:58:46 -07:00
parent 20284aa77c
commit 61f42183fd

View File

@ -18,26 +18,15 @@ struct insn {
} __packed;
struct insn_args {
unsigned long *target;
struct insn *insn;
ssize_t size;
struct jump_entry *entry;
enum jump_label_type type;
};
static int __arch_jump_label_transform(void *data)
static void __jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
struct insn_args *args = data;
int rc;
rc = probe_kernel_write(args->target, args->insn, args->size);
WARN_ON_ONCE(rc < 0);
return 0;
}
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
struct insn_args args;
struct insn insn;
int rc;
if (type == JUMP_LABEL_ENABLE) {
/* brcl 15,offset */
@ -49,11 +38,33 @@ void arch_jump_label_transform(struct jump_entry *entry,
insn.offset = 0;
}
args.target = (void *) entry->code;
args.insn = &insn;
args.size = JUMP_LABEL_NOP_SIZE;
rc = probe_kernel_write((void *)entry->code, &insn, JUMP_LABEL_NOP_SIZE);
WARN_ON_ONCE(rc < 0);
}
stop_machine(__arch_jump_label_transform, &args, NULL);
static int __sm_arch_jump_label_transform(void *data)
{
struct insn_args *args = data;
__jump_label_transform(args->entry, args->type);
return 0;
}
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
struct insn_args args;
args.entry = entry;
args.type = type;
stop_machine(__sm_arch_jump_label_transform, &args, NULL);
}
void arch_jump_label_transform_static(struct jump_entry *entry,
enum jump_label_type type)
{
__jump_label_transform(entry, type);
}
#endif