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 43843C3DA7F for ; Wed, 31 Jul 2024 08:25:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9Ohyf01z+RQdbQQcz4+PP/EvJqHgnb9g8adgwYo0As8=; b=RrkHp4jMGxsKv/tCQxAeH2j6ng Q2MMphfM4AzdD5+y0M+C6PkJTT43aTmRxEC1LITS9Azz/C9dyozvrT68i3vtaQV7LJS43JBgLYsHA i2OFtgnvQo4MxbHmyThpqj3ATP8aHawQ8SRxnDuuhXwjCvsHOOsxrM70sWQ+1a86xDA091S4SXCUE d5h74Hc3Rvts9Hclpxi6JPZy+Z/8NrL+uJgK7gAoSMoManFQkQDLZkOeiMs5vV/daeqcuRoKn/0Hc sOGuj1ddLGajRKTAuqxF3zTfmZyfuP+jpZW+Zci3It9CkCKpXzCEGkU0rbYF+Qc7/B4csT2xyAZ8b y8rjcsdA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZ4eL-00000000JBB-3Ujd; Wed, 31 Jul 2024 08:25:33 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:32c8:5054:ff:fe00:142]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZ4dt-00000000J5b-0DUP for linux-arm-kernel@lists.infradead.org; Wed, 31 Jul 2024 08:25:06 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=9Ohyf01z+RQdbQQcz4+PP/EvJqHgnb9g8adgwYo0As8=; b=qPifwyiAX5xb8gnHPkVc5vS3zC RT5FqN29h0hS/WprOebZI85qTmsYpZaejB9WhdNcrwsxSdYSJI0QSgn2INPKdKdll53n/D1YAhdp8 gwB2L4KmKY1xgxqUw+DJ2n5FVvb+qSSkZFLMGPWkQFvae7FOhuJ0HUyIkjxge3H449D1fgYrLkdO4 XleptULGrZfO7P0MubCgGChxybTVRcZosZ38IqC1HpZvA4NJ/mZ22b0cWuwO02B1KRbG8Rojx/M61 rXNVMvDS9pXywgSmJRZoVVoyGQuVvbtasj9zj2WHEi8PNcwwiyrVkT/9QLe5vv86DSBxfEcuziJz0 ZDG1+22g==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:60238) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1sZ4dO-0008GX-0p; Wed, 31 Jul 2024 09:24:34 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1sZ4dM-00063s-9V; Wed, 31 Jul 2024 09:24:32 +0100 Date: Wed, 31 Jul 2024 09:24:32 +0100 From: "Russell King (Oracle)" To: Jinjie Ruan Cc: arnd@arndb.de, afd@ti.com, akpm@linux-foundation.org, linus.walleij@linaro.org, eric.devolder@oracle.com, robh@kernel.org, vincent.whitchurch@axis.com, bhe@redhat.com, nico@fluxnic.net, ardb@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: [PATCH] ARM: support PREEMPT_DYNAMIC Message-ID: References: <20240620090028.729373-1-ruanjinjie@huawei.com> <79a3de7c-21da-12ce-8372-9c9029c237ac@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <79a3de7c-21da-12ce-8372-9c9029c237ac@huawei.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240731_012505_116868_B409F961 X-CRM114-Status: UNSURE ( 9.97 ) 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 On Wed, Jul 31, 2024 at 10:07:53AM +0800, Jinjie Ruan wrote: > > #ifdef CONFIG_PREEMPTION > > +#ifdef CONFIG_PREEMPT_DYNAMIC > > + bl need_irq_preemption > > + cmp r0, #0 > > + beq 2f > > +#endif Depending on the interrupt rate, this can be regarded as a fast path, it would be nice if we could find a way to use static branches in assembly code. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!