From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754632AbaKZXVI (ORCPT ); Wed, 26 Nov 2014 18:21:08 -0500 Received: from terminus.zytor.com ([198.137.202.10]:59125 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752760AbaKZXVE (ORCPT ); Wed, 26 Nov 2014 18:21:04 -0500 Date: Wed, 26 Nov 2014 15:20:08 -0800 From: tip-bot for Jiang Liu Message-ID: Cc: mingo@kernel.org, rdunlap@infradead.org, bhelgaas@google.com, hpa@zytor.com, tony.luck@intel.com, rjw@rjwysocki.net, jiang.liu@linux.intel.com, grant.likely@linaro.org, konrad.wilk@oracle.com, bp@alien8.de, gregkh@linuxfoundation.org, tglx@linutronix.de, yinghai@kernel.org, joro@8bytes.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org, jroedel@suse.de Reply-To: benh@kernel.crashing.org, linux-kernel@vger.kernel.org, joro@8bytes.org, jroedel@suse.de, tglx@linutronix.de, yinghai@kernel.org, grant.likely@linaro.org, konrad.wilk@oracle.com, jiang.liu@linux.intel.com, tony.luck@intel.com, rjw@rjwysocki.net, gregkh@linuxfoundation.org, bp@alien8.de, mingo@kernel.org, hpa@zytor.com, bhelgaas@google.com, rdunlap@infradead.org In-Reply-To: <1416901802-24211-30-git-send-email-jiang.liu@linux.intel.com> References: <1416901802-24211-30-git-send-email-jiang.liu@linux.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/apic] x86, irq: Use cached IOAPIC entry instead of reading from hardware Git-Commit-ID: fda7c08b1349cc4c65f8a5240b10f7e9938604b8 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: fda7c08b1349cc4c65f8a5240b10f7e9938604b8 Gitweb: http://git.kernel.org/tip/fda7c08b1349cc4c65f8a5240b10f7e9938604b8 Author: Jiang Liu AuthorDate: Tue, 25 Nov 2014 15:49:53 +0800 Committer: Thomas Gleixner CommitDate: Wed, 26 Nov 2014 23:52:49 +0100 x86, irq: Use cached IOAPIC entry instead of reading from hardware Use cached IOAPIC entry instead of reading data from IOAPIC hardware registers to improve performance. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Tony Luck Cc: Joerg Roedel Cc: Greg Kroah-Hartman Cc: Bjorn Helgaas Cc: Benjamin Herrenschmidt Cc: Rafael J. Wysocki Cc: Randy Dunlap Cc: Yinghai Lu Cc: Borislav Petkov Cc: Grant Likely Link: http://lkml.kernel.org/r/1416901802-24211-30-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner Tested-by: Joerg Roedel --- arch/x86/kernel/apic/io_apic.c | 78 ++++++++++++------------------------------ 1 file changed, 21 insertions(+), 57 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index a915ee0..8a62933 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -69,8 +69,13 @@ int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity); /* - * Is the SiS APIC rmw bug present ? + * Is the SiS APIC rmw bug present ? * -1 = don't know, 0 = no, 1 = yes + * When doing a read-modify-write operation on IOAPIC registers, older SiS APIC + * requires we rewrite the index register again where the read already set up + * the index register. + * The code to make use of sis_apic_bug has been removed, but we don't want to + * loss this knowledge. */ int sis_apic_bug = -1; @@ -290,22 +295,6 @@ static void io_apic_write(unsigned int apic, unsigned int reg, writel(value, &io_apic->data); } -/* - * Re-write a value: to be used for read-modify-write - * cycles where the read already set up the index register. - * - * Older SiS APIC requires we rewrite the index register - */ -static void io_apic_modify(unsigned int apic, unsigned int reg, - unsigned int value) -{ - struct io_apic __iomem *io_apic = io_apic_base(apic); - - if (sis_apic_bug) - writel(reg, &io_apic->index); - writel(value, &io_apic->data); -} - union entry_union { struct { u32 w1, w2; }; struct IO_APIC_route_entry entry; @@ -442,29 +431,23 @@ static void __init replace_pin_at_irq_node(struct mp_chip_data *data, int node, add_pin_to_irq_node(data, node, newapic, newpin); } -static void __io_apic_modify_irq(struct irq_pin_list *entry, - int mask_and, int mask_or, - void (*final)(struct irq_pin_list *entry)) -{ - unsigned int reg, pin; - - pin = entry->pin; - reg = io_apic_read(entry->apic, 0x10 + pin * 2); - reg &= mask_and; - reg |= mask_or; - io_apic_modify(entry->apic, 0x10 + pin * 2, reg); - if (final) - final(entry); -} - static void io_apic_modify_irq(struct mp_chip_data *data, int mask_and, int mask_or, void (*final)(struct irq_pin_list *entry)) { + union entry_union eu; struct irq_pin_list *entry; - for_each_irq_pin(entry, data->irq_2_pin) - __io_apic_modify_irq(entry, mask_and, mask_or, final); + eu.entry = data->entry; + eu.w1 &= mask_and; + eu.w1 |= mask_or; + data->entry = eu.entry; + + for_each_irq_pin(entry, data->irq_2_pin) { + io_apic_write(entry->apic, 0x10 + 2 * entry->pin, eu.w1); + if (final) + final(entry); + } } static void io_apic_sync(struct irq_pin_list *entry) @@ -1729,28 +1712,6 @@ static unsigned int startup_ioapic_irq(struct irq_data *data) return was_pending; } -static void __target_IO_APIC_irq(unsigned int irq, struct irq_cfg *cfg, - struct mp_chip_data *data) -{ - int apic, pin; - struct irq_pin_list *entry; - u8 vector = cfg->vector; - unsigned int dest = SET_APIC_LOGICAL_ID(cfg->dest_apicid); - - for_each_irq_pin(entry, data->irq_2_pin) { - unsigned int reg; - - apic = entry->apic; - pin = entry->pin; - - io_apic_write(apic, 0x11 + pin*2, dest); - reg = io_apic_read(apic, 0x10 + pin*2); - reg &= ~IO_APIC_REDIR_VECTOR_MASK; - reg |= vector; - io_apic_modify(apic, 0x10 + pin*2, reg); - } -} - atomic_t irq_mis_count; #ifdef CONFIG_GENERIC_PENDING_IRQ @@ -1916,6 +1877,7 @@ static int ioapic_set_affinity(struct irq_data *irq_data, { struct irq_data *parent = irq_data->parent_data; struct mp_chip_data *data = irq_data->chip_data; + struct irq_pin_list *entry; struct irq_cfg *cfg; unsigned long flags; int ret; @@ -1926,7 +1888,9 @@ static int ioapic_set_affinity(struct irq_data *irq_data, cfg = irqd_cfg(irq_data); data->entry.dest = SET_APIC_LOGICAL_ID(cfg->dest_apicid); data->entry.vector = cfg->vector; - __target_IO_APIC_irq(irq_data->irq, cfg, irq_data->chip_data); + for_each_irq_pin(entry, data->irq_2_pin) + __ioapic_write_entry(entry->apic, entry->pin, + data->entry); } raw_spin_unlock_irqrestore(&ioapic_lock, flags);