From patchwork Tue Sep 13 03:34:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Liao, Chang" X-Patchwork-Id: 12974304 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4F372C54EE9 for ; Tue, 13 Sep 2022 03:40:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=9+UGTecdu104re+kLogksAAqZGN99OR+gz/p4RNptwo=; b=SfP1ZOk4Slwx96 wSgCKnza7+FntBsTYYjai+Xk5OhbHXZsAjrthYF4epzMAd1wVmsZ5NqPChrt66GqwbzsY1C3hKJ1c sF/UVl534RsR1KstcUy/ZXJGxY1CqH1dqLBs2kvj3fu/jyEtXIFaM3BR7cDSNDeOXolbO2IbQ7VFQ D8qq2lKxnKhPAtLSFC2qYLV5IG5uBgL9+Ju7m1czHx5pCC2Z+VGW6+EgR2rfGjPyx4JRIUZ7tnfaY wJ7tN3GCr5ChpUpL3mkZWzEDCjmo9TWvi/RiETYC77a4Bdegno4BCMYlkeoF4yhKFMREBelIKWwYH /mwGTHxyd8xOmopW51lA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oXwks-00141F-NL; Tue, 13 Sep 2022 03:38:34 +0000 Received: from szxga03-in.huawei.com ([45.249.212.189]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oXwko-0013wy-EQ; Tue, 13 Sep 2022 03:38:32 +0000 Received: from kwepemi500012.china.huawei.com (unknown [172.30.72.53]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4MRTf16HnPzHntv; Tue, 13 Sep 2022 11:36:25 +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 15.1.2375.24; Tue, 13 Sep 2022 11:38:25 +0800 From: Liao Chang To: , , , , , , , , , , CC: , , , Subject: [PATCH V2 2/3] csky/kprobe: Optimize the performance of patching single-step slot Date: Tue, 13 Sep 2022 11:34:53 +0800 Message-ID: <20220913033454.104519-3-liaochang1@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220913033454.104519-1-liaochang1@huawei.com> References: <20220913033454.104519-1-liaochang1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.67.174.53] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemi500012.china.huawei.com (7.221.188.12) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220912_203830_706353_9C903955 X-CRM114-Status: UNSURE ( 7.75 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. 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/kprobes.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) p->ainsn.api.restore = (unsigned long)p->addr + offset; - 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); } static void __kprobes arch_prepare_simulate(struct kprobe *p)