From patchwork Tue Feb 20 13:01:20 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 10230031 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0EFB6602DC for ; Tue, 20 Feb 2018 13:03:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F282D28658 for ; Tue, 20 Feb 2018 13:03:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E741528660; Tue, 20 Feb 2018 13:03:55 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 952D028658 for ; Tue, 20 Feb 2018 13:03:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=7EjiH3BxBZcltPohmYr/bzjGmqExtTYC59okwTC/T4A=; b=EqBPWxCbd6H7bCyCHy9Nx2DrAN FIGkhLbPNJ3+ynSltKL9Oq5X6BNuH2C7fmIh7+j9mngdo88J7PI1MN/XlhdIXM+oyylUEDcddnvbL Jzh3GhGZlR0jKn4lFF4asJAT6DJungWqnBAyndYeycXDztUZLMCqhhhyeFE7U73Zu//fKbeoqpJhU jQsmVG9DjY0UXkCaLCYxxJULBqI8209k/i5N6bmj1ou5hgl8LhVBiVjl7m/oZ4eJjUbEt6u4Y7vn4 LETRnFeZPiDOZQpqxU23sNtDns9kf9j45q2tiX4oC2ij1ax3BeMjdcAXFLf+nNEmojS2PCMabgNpg SkvmYpGw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1eo7aI-0006va-GX; Tue, 20 Feb 2018 13:03:50 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1eo7YB-0005p4-In; Tue, 20 Feb 2018 13:01:47 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E28A915BF; Tue, 20 Feb 2018 05:01:32 -0800 (PST) Received: from approximate.cambridge.arm.com (approximate.cambridge.arm.com [10.1.207.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 718DE3F318; Tue, 20 Feb 2018 05:01:31 -0800 (PST) From: Marc Zyngier To: Sandy Huang , =?UTF-8?q?Heiko=20St=C3=BCbner?= Subject: [PATCH 3/3] drm/rockchip: Don't use spin_lock_irqsave in interrupt context Date: Tue, 20 Feb 2018 13:01:20 +0000 Message-Id: <20180220130120.5254-4-marc.zyngier@arm.com> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180220130120.5254-1-marc.zyngier@arm.com> References: <20180220130120.5254-1-marc.zyngier@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180220_050139_724449_5CBCBE3A X-CRM114-Status: UNSURE ( 9.40 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+patchwork-linux-rockchip=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The rockchip DRM driver is quite careful to disable interrupts when taking a lock that is also taken in interrupt context, which is a good thing. What is a bit over the top is to use spin_lock_irqsave when already in interrupt context, as you cannot take another interrupt again, and disabling interrupt is just pure overhead. Switching to the non _irqsave version in interrupt context is more logical, and less heavy handed. Signed-off-by: Marc Zyngier --- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index f2bde1c76bbe..48d27f6fb16d 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -1160,15 +1160,14 @@ static void vop_handle_vblank(struct vop *vop) { struct drm_device *drm = vop->drm_dev; struct drm_crtc *crtc = &vop->crtc; - unsigned long flags; - spin_lock_irqsave(&drm->event_lock, flags); + spin_lock(&drm->event_lock); if (vop->event) { drm_crtc_send_vblank_event(crtc, vop->event); drm_crtc_vblank_put(crtc); vop->event = NULL; } - spin_unlock_irqrestore(&drm->event_lock, flags); + spin_unlock(&drm->event_lock); if (test_and_clear_bit(VOP_PENDING_FB_UNREF, &vop->pending)) drm_flip_work_commit(&vop->fb_unref_work, system_unbound_wq); @@ -1179,21 +1178,20 @@ static irqreturn_t vop_isr(int irq, void *data) struct vop *vop = data; struct drm_crtc *crtc = &vop->crtc; uint32_t active_irqs; - unsigned long flags; int ret = IRQ_NONE; /* * interrupt register has interrupt status, enable and clear bits, we * must hold irq_lock to avoid a race with enable/disable_vblank(). */ - spin_lock_irqsave(&vop->irq_lock, flags); + spin_lock(&vop->irq_lock); active_irqs = VOP_INTR_GET_TYPE(vop, status, INTR_MASK); /* Clear all active interrupt sources */ if (active_irqs) VOP_INTR_SET_TYPE(vop, clear, active_irqs, 1); - spin_unlock_irqrestore(&vop->irq_lock, flags); + spin_unlock(&vop->irq_lock); /* This is expected for vop iommu irqs, since the irq is shared */ if (!active_irqs)