Commit e71a5be1 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge
Browse files

x86/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: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: default avatarJason Baron <jbaron@redhat.com>
Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
parent 61f42183

arch/x86/kernel/jump_label.c

+17 −3
Original line number Diff line number Diff line
@@ -24,8 +24,9 @@ union jump_code_union { 
	} __attribute__((packed));

};



void arch_jump_label_transform(struct jump_entry *entry,

			       enum jump_label_type type)

static void __jump_label_transform(struct jump_entry *entry,

				   enum jump_label_type type,

				   void *(*poker)(void *, const void *, size_t))

{

	union jump_code_union code;
@@ -35,11 +36,24 @@ void arch_jump_label_transform(struct jump_entry *entry, 
				(entry->code + JUMP_LABEL_NOP_SIZE);

	} else

		memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE);



	(*poker)((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE);

}



void arch_jump_label_transform(struct jump_entry *entry,

			       enum jump_label_type type)

{

	get_online_cpus();

	mutex_lock(&text_mutex);

	text_poke_smp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE);

	__jump_label_transform(entry, type, text_poke_smp);

	mutex_unlock(&text_mutex);

	put_online_cpus();

}



void arch_jump_label_transform_static(struct jump_entry *entry,

				      enum jump_label_type type)

{

	__jump_label_transform(entry, type, text_poke_early);

}



#endif