x86: Make jump_label use int3-based patching (51b2c07b) · Commits · 戴 / test

Make jump labels use text_poke_bp() for text patching instead of text_poke_smp(), avoiding the need for stop_machine(). Reviewed-by:

arch/x86/kernel/jump_label.c

+14 −2

Original line number	Diff line number	Diff line
		@@ -37,7 +37,19 @@ static void __jump_label_transform(struct jump_entry *entry,
		} else
		memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE);

		/*
		* Make text_poke_bp() a default fallback poker.
		*
		* At the time the change is being done, just ignore whether we
		* are doing nop -> jump or jump -> nop transition, and assume
		* always nop being the 'currently valid' instruction
		*
		*/
		if (poker)
		(poker)((void )entry->code, &code, JUMP_LABEL_NOP_SIZE);
		else
		text_poke_bp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE,
		(void *)entry->code + JUMP_LABEL_NOP_SIZE);
		}

		void arch_jump_label_transform(struct jump_entry *entry,
		@@ -45,7 +57,7 @@ void arch_jump_label_transform(struct jump_entry *entry,
		{
		get_online_cpus();
		mutex_lock(&text_mutex);
		__jump_label_transform(entry, type, text_poke_smp);
		__jump_label_transform(entry, type, NULL);
		mutex_unlock(&text_mutex);
		put_online_cpus();
		}