From patchwork Wed Nov 26 16:23:26 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Thompson X-Patchwork-Id: 5386701 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id F252DC11AD for ; Wed, 26 Nov 2014 16:30:58 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1D134201FB for ; Wed, 26 Nov 2014 16:30:58 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 39B6B201CD for ; Wed, 26 Nov 2014 16:30:57 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XtfRr-0001AJ-Cr; Wed, 26 Nov 2014 16:28:11 +0000 Received: from mail-wi0-f169.google.com ([209.85.212.169]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XtfOF-00068N-Ux for linux-arm-kernel@lists.infradead.org; Wed, 26 Nov 2014 16:24:29 +0000 Received: by mail-wi0-f169.google.com with SMTP id r20so15973144wiv.0 for ; Wed, 26 Nov 2014 08:24:05 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=4QCPEEtO4A1jSa4uotPOU/OLE4NeWW/xoKt5HS6g1lo=; b=YpN18pkzT9eaBjFcGaUtetzY7GukVJLx4Bg3ejfBNbGFyA/N3SRgqJ0LYvFF3P6ddf UM/Lg5/V4XvN3mq5pJDHscJeeU423LHJkbZxe9PBUFmkJ5kjte46jir9P09QWSx9i89Y IkXjV0WRxHaMxky9Hotddf858s87XgwPCxNrNAl33TSO2qW5tMcgogRM9XPNAX6gw2lR WKymqXxru2/gnztp0EC2fBRfIJfnc86Mg4TTe6zh3huuV2u2sF7UypRmujMjJheozTh/ G4m1ZUSlJmAG9BZ2RaadJnThOhiJ0W80adJOI98ch/B6kMH8K4cE2U5fzPCJdERmYdQC 8Fqg== X-Gm-Message-State: ALoCoQn/xGytLu4Y56pAsDhtWH1H5oHB2iKIkrWNhCbokwjgXUE5yh0apaSVf7ydv5/Io8eyB3dA X-Received: by 10.194.61.115 with SMTP id o19mr52019575wjr.12.1417019045009; Wed, 26 Nov 2014 08:24:05 -0800 (PST) Received: from sundance.lan (cpc4-aztw19-0-0-cust157.18-1.cable.virginm.net. [82.33.25.158]) by mx.google.com with ESMTPSA id pl6sm7869071wic.22.2014.11.26.08.24.02 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 26 Nov 2014 08:24:04 -0800 (PST) From: Daniel Thompson To: Thomas Gleixner , Jason Cooper Subject: [PATCH 3.18-rc4 v10 2/6] irqchip: gic: Optimize locking in gic_raise_softirq Date: Wed, 26 Nov 2014 16:23:26 +0000 Message-Id: <1417019010-9220-3-git-send-email-daniel.thompson@linaro.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1417019010-9220-1-git-send-email-daniel.thompson@linaro.org> References: <1415968543-29469-1-git-send-email-daniel.thompson@linaro.org> <1417019010-9220-1-git-send-email-daniel.thompson@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141126_082428_176381_3180E680 X-CRM114-Status: GOOD ( 12.84 ) X-Spam-Score: -0.7 (/) Cc: Daniel Thompson , linaro-kernel@lists.linaro.org, Russell King , patches@linaro.org, Marc Zyngier , Stephen Boyd , linux-kernel@vger.kernel.org, Daniel Drake , Dmitry Pervushin , Dirk Behme , John Stultz , Tim Sander , Sumit Semwal , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_LOW, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently gic_raise_softirq() unconditionally takes and releases a lock whose only purpose is to synchronize with the b.L switcher. Remove this lock if the b.L switcher is not compiled in. Signed-off-by: Daniel Thompson Cc: Thomas Gleixner Cc: Jason Cooper Cc: Russell King Cc: Marc Zyngier --- drivers/irqchip/irq-gic.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c index 94d77118efa8..e875da93f24a 100644 --- a/drivers/irqchip/irq-gic.c +++ b/drivers/irqchip/irq-gic.c @@ -76,8 +76,23 @@ static DEFINE_RAW_SPINLOCK(irq_controller_lock); * This lock is used by the big.LITTLE migration code to ensure no IPIs * can be pended on the old core after the map has been updated. */ +#ifdef CONFIG_BL_SWITCHER static DEFINE_RAW_SPINLOCK(cpu_map_migration_lock); +static inline void bl_migration_lock(unsigned long *flags) +{ + raw_spin_lock_irqsave(&cpu_map_migration_lock, *flags); +} + +static inline void bl_migration_unlock(unsigned long flags) +{ + raw_spin_unlock_irqrestore(&cpu_map_migration_lock, flags); +} +#else +static inline void bl_migration_lock(unsigned long *flags) {} +static inline void bl_migration_unlock(unsigned long flags) {} +#endif + /* * The GIC mapping of CPU interfaces does not necessarily match * the logical CPU numbering. Let's use a mapping as returned @@ -630,7 +645,7 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) int cpu; unsigned long flags, map = 0; - raw_spin_lock_irqsave(&cpu_map_migration_lock, flags); + bl_migration_lock(&flags); /* Convert our logical CPU mask into a physical one. */ for_each_cpu(cpu, mask) @@ -645,7 +660,7 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) /* this always happens on GIC0 */ writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT); - raw_spin_unlock_irqrestore(&cpu_map_migration_lock, flags); + bl_migration_unlock(flags); } #endif