From nobody Mon Apr 6 09:15:09 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B3A6C07E9D for ; Tue, 27 Sep 2022 02:28:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230253AbiI0C2t (ORCPT ); Mon, 26 Sep 2022 22:28:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230168AbiI0C2Y (ORCPT ); Mon, 26 Sep 2022 22:28:24 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DD2FA9C01; Mon, 26 Sep 2022 19:28:23 -0700 (PDT) Received: from kwepemi500012.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Mc3MV6nRfzHtfM; Tue, 27 Sep 2022 10:23:34 +0800 (CST) Received: from huawei.com (10.67.174.53) by kwepemi500012.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 27 Sep 2022 10:28:20 +0800 From: Liao Chang To: , , , , , , , , , , CC: , , , Subject: [PATCH 2/3] csky/kprobe: Optimize the performance of patching single-step slot Date: Tue, 27 Sep 2022 10:24:34 +0800 Message-ID: <20220927022435.129965-3-liaochang1@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220927022435.129965-1-liaochang1@huawei.com> References: <20220927022435.129965-1-liaochang1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.67.174.53] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemi500012.china.huawei.com (7.221.188.12) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Single-step slot would not be used until kprobe is enabled, that means no race condition occurs on it under SMP, hence it is safe to pacth ss slot without stopping machine. Acked-by: Masami Hiramatsu (Google) Signed-off-by: Liao Chang --- arch/csky/kernel/probes/kprobes.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/csky/kernel/probes/kprobes.c b/arch/csky/kernel/probes/kp= robes.c index 3c6e5c725d81..4feb5ce16264 100644 --- a/arch/csky/kernel/probes/kprobes.c +++ b/arch/csky/kernel/probes/kprobes.c @@ -57,7 +57,11 @@ static void __kprobes arch_prepare_ss_slot(struct kprobe= *p) =20 p->ainsn.api.restore =3D (unsigned long)p->addr + offset; =20 - patch_text(p->ainsn.api.insn, p->opcode); + memcpy(p->ainsn.api.insn, &p->opcode, offset); + dcache_wb_range((unsigned long)p->ainsn.api.insn, + (unsigned long)p->ainsn.api.insn + offset); + icache_inv_range((unsigned long)p->ainsn.api.insn, + (unsigned long)p->ainsn.api.insn + offset); } =20 static void __kprobes arch_prepare_simulate(struct kprobe *p) --=20 2.17.1