From mboxrd@z Thu Jan 1 00:00:00 1970 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 DA470C6FD1D for ; Wed, 15 Mar 2023 23:44:34 +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:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=CtKzer35A4jCc2Uc4ko0iN4qNbulaLFAlJsLHu8wzio=; b=u9daK5wBuy9b/f WECVGPnAO/XZwKcvMUDiKHNNC7lGBFiNcdmeiodYagwXihWW+S88ugokuBrifqryksOA0i7/e83x0 w5WFrFPjVDC8eS1aG1T3xLHRbwHjY1ylb5StdS6lVZmRqYeRS2eI6knWvqg05Zfu6sxRkJyX1EYCf kXnwyHlTAWBERAbDTyeQPEMtE3GsstExBNnhZYNAsqsSqdcWZ6drQ75Xe2lSu6oy1T3wHFUWQ9gVI ycMHgjBjOzPhHfAGNVtEjEsnlZI7WQWaiKmdjZBZfZ5evjWOgJkbkqP4m2ITzISVn/wA6/yP6hAuV o7uH3mZDdA5erPVSD9bg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pcamV-00Ekmk-2y; Wed, 15 Mar 2023 23:43:43 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pcamS-00EkmC-1T for linux-arm-kernel@lists.infradead.org; Wed, 15 Mar 2023 23:43:41 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 07F6D61E8D; Wed, 15 Mar 2023 23:43:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9067C433D2; Wed, 15 Mar 2023 23:43:37 +0000 (UTC) Date: Wed, 15 Mar 2023 19:43:34 -0400 From: Steven Rostedt To: Florent Revest Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, catalin.marinas@arm.com, will@kernel.org, mhiramat@kernel.org, mark.rutland@arm.com, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, kpsingh@kernel.org, jolsa@kernel.org, xukuohai@huaweicloud.com, lihuafei1@huawei.com Subject: Re: [PATCH v2 04/10] ftrace: Store direct called addresses in their ops Message-ID: <20230315194334.58eb56ab@gandalf.local.home> In-Reply-To: <20230207182135.2671106-5-revest@chromium.org> References: <20230207182135.2671106-1-revest@chromium.org> <20230207182135.2671106-5-revest@chromium.org> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230315_164340_533751_06268ECD X-CRM114-Status: GOOD ( 12.89 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, 7 Feb 2023 19:21:29 +0100 Florent Revest wrote: > @@ -5445,6 +5445,7 @@ __modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr) > /* Enable the tmp_ops to have the same functions as the direct ops */ > ftrace_ops_init(&tmp_ops); > tmp_ops.func_hash = ops->func_hash; > + tmp_ops.direct_call = addr; > > err = register_ftrace_function_nolock(&tmp_ops); > if (err) > @@ -5466,6 +5467,7 @@ __modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr) > entry->direct = addr; > } > } > + WRITE_ONCE(ops->direct_call, addr); I'm curious about the use of WRITE_ONCE(). It should not go outside the mutex barrier. -- Steve > > mutex_unlock(&ftrace_lock); > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel