From patchwork Tue Sep 26 12:54:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 13399229 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 D9720E7E62F for ; Tue, 26 Sep 2023 12:55:54 +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: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:In-Reply-To:References: List-Owner; bh=ayav/Qv9EJNE3wbNWTBs/55NYKmloJbvP73qyAGjAuU=; b=pIN8IF+awdAKmS oPJI2kITc0ePRb7N2FNehbVYyLhylVq0eq3Z5L+zdVx2aqKxUpIQOzQUW0h/JV/tHnUByl9PlwZh/ tYCcMPmZ+8kmF+prVIoPvxeKsE0C9pPM111Cd1Ow1y0pFUcoiLqiGmP2lKMMKC+Iinnxph4NGbf7n eEttkhu+k7Qv2TGG5ta+WIvPdhDYZNlXjCZ5qQTknqnJxRbHG7pm8+lZxbHXJhH3PvqSsrsy+ftoS FLVBaDDS8eRhPzsjV8R3AkHQVLuHlFzEe4ManM2i3iMkyVxaAxuULejX1eUyMlJ4w0f1LX5nxo7F8 Dt6CIV1HVxqvLBu007NQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1ql7b8-00GPB9-2m; Tue, 26 Sep 2023 12:55:30 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1ql7aw-00GP7K-0i for linux-arm-kernel@lists.infradead.org; Tue, 26 Sep 2023 12:55:20 +0000 From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1695732914; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=7FvZrIiPXhVv+mQ/7QFfcdtEraght5v1dBXqw6hDjnw=; b=cTNWeUBdnMV0Y93s5BR2fdARIZeBcNclkKLvv6ALRI60I/hUerYd3rRc/kexiuqsCYdA3R R55/x4ofQopU5USMw8vOxhodD+OyMVMLDtMZv0UZojyU07DdGCEX6vmfgu2yECnleNSQje acz/1i/SV+OJAXMS3UWcjqZjl7PlUY0PryYjk93U5cTK4xXjVzXkOOK7/XjNlM5dav0U6z +8uewhjFNOaxrhdEFmdeFMdZdm3jeOApH8uzXY7nBpeL+0qpxX6s/bTsr1DK51vz51JROz aBQhgjSnP+xiBLVWbRCMmLyZYkM7CcMdsa12nAfLPUPdrkZ6mqNlHnjXEIEUaQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1695732914; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=7FvZrIiPXhVv+mQ/7QFfcdtEraght5v1dBXqw6hDjnw=; b=nk5oGfOhUvip04mM3Lfja85cAfYZ+rbcihoQoKBNHnIGg7Le7HKEVv8IYWk3OKm4NBLgmh zdgs0PGrpyy8gBCA== To: linux-arm-kernel@lists.infradead.org, linux@armlinux.org.uk Cc: ardb@kernel.org, tglx@linutronix.de Subject: [PATCH v3 0/4] ARM: vfp: Introduce vfp_lock() for VFP locking. Date: Tue, 26 Sep 2023 14:54:58 +0200 Message-Id: <20230926125502.1127015-1-bigeasy@linutronix.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230926_055518_401157_D37806E5 X-CRM114-Status: UNSURE ( 5.83 ) 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 There was a bug report on PREEMPT_RT which made me look into VFP locking on ARM. The usage of local_bh_disable() to ensure exclusive access to the VFP unit is not working on PREEMPT_RT because the softirq context is preemptible. This series introduces vfp_lock() which does the right thing. v2…v3: - Repost with Ard's Reviewed-by tag. v1…v2: https://lore.kernel.org/all/20230628080516.798032-1-bigeasy@linutronix.de - Split the last patch into two patches (3 and 4 of this series). Suggested by Ard. v1: https://lore.kernel.org/all/20230615101656.1308942-1-bigeasy@linutronix.de Sebastian