Commit-ID: 51b2c07b22261f19188d9a9071943d60a067481c Gitweb: http://git.kernel.org/tip/51b2c07b22261f19188d9a9071943d60a067481c Author: Jiri Kosina <jkos...@suse.cz> AuthorDate: Fri, 12 Jul 2013 11:22:09 +0200 Committer: H. Peter Anvin <h...@linux.intel.com> CommitDate: Tue, 16 Jul 2013 17:55:37 -0700
x86: Make jump_label use int3-based patching Make jump labels use text_poke_bp() for text patching instead of text_poke_smp(), avoiding the need for stop_machine(). Reviewed-by: Steven Rostedt <rost...@goodmis.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> Signed-off-by: Jiri Kosina <jkos...@suse.cz> Link: http://lkml.kernel.org/r/alpine.lnx.2.00.1307121120250.29...@pobox.suse.cz Signed-off-by: H. Peter Anvin <h...@linux.intel.com> --- arch/x86/kernel/jump_label.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c index 2889b3d..460f5d9 100644 --- a/arch/x86/kernel/jump_label.c +++ b/arch/x86/kernel/jump_label.c @@ -37,7 +37,19 @@ static void __jump_label_transform(struct jump_entry *entry, } else memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE); - (*poker)((void *)entry->code, &code, 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(); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
