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| author | Jiang Liu <jiang.liu@linux.intel.com> | 2014-11-02 14:04:29 +0800 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2014-12-16 14:08:15 +0100 |
| commit | 5da2fd26193433006255d534b3a01eae37e58428 (patch) | |
| tree | fcdb10ab31f9290cd53e61d081a829ded689df12 /arch/x86/kernel | |
| parent | 35ef9c941c93f72bb49fe01396fc963ab80105bd (diff) | |
| download | linux-5da2fd26193433006255d534b3a01eae37e58428.tar.bz2 | |
x86, irq, ACPI: Introduce a mutex to protect IOAPIC operations from hotplug
We are going to support ACPI based IOAPIC hotplug, so introduce a mutex
to protect IOAPIC data structures from IOAPIC hotplug. We choose to
serialize in ACPI instead of in the IOAPIC core because:
1) currently we only plan to support ACPI based IOAPIC hotplug
2) it's much more cleaner and easier
3) It does't affect IOAPIC discovered by devicetree, SFI and mpparse.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Link: http://lkml.kernel.org/r/1414908273-7552-15-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/acpi/boot.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 6ddeba31bd98..2d76f022adc2 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -76,6 +76,19 @@ int acpi_fix_pin2_polarity __initdata; static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE; #endif +/* + * Locks related to IOAPIC hotplug + * Hotplug side: + * ->device_hotplug_lock + * ->acpi_ioapic_lock + * ->ioapic_lock + * Interrupt mapping side: + * ->acpi_ioapic_lock + * ->ioapic_mutex + * ->ioapic_lock + */ +static DEFINE_MUTEX(acpi_ioapic_lock); + /* -------------------------------------------------------------------------- Boot-time Configuration -------------------------------------------------------------------------- */ @@ -609,8 +622,10 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp) if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) { *irqp = gsi; } else { + mutex_lock(&acpi_ioapic_lock); irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC | IOAPIC_MAP_CHECK); + mutex_unlock(&acpi_ioapic_lock); if (irq < 0) return -1; *irqp = irq; @@ -650,7 +665,9 @@ static int acpi_register_gsi_ioapic(struct device *dev, u32 gsi, int irq = gsi; #ifdef CONFIG_X86_IO_APIC + mutex_lock(&acpi_ioapic_lock); irq = mp_register_gsi(dev, gsi, trigger, polarity); + mutex_unlock(&acpi_ioapic_lock); #endif return irq; @@ -659,7 +676,9 @@ static int acpi_register_gsi_ioapic(struct device *dev, u32 gsi, static void acpi_unregister_gsi_ioapic(u32 gsi) { #ifdef CONFIG_X86_IO_APIC + mutex_lock(&acpi_ioapic_lock); mp_unregister_gsi(gsi); + mutex_unlock(&acpi_ioapic_lock); #endif } @@ -1187,7 +1206,9 @@ static void __init acpi_process_madt(void) /* * Parse MADT IO-APIC entries */ + mutex_lock(&acpi_ioapic_lock); error = acpi_parse_madt_ioapic_entries(); + mutex_unlock(&acpi_ioapic_lock); if (!error) { acpi_set_irq_model_ioapic(); |