Commit 5da2fd26 authored by Jiang Liu's avatar Jiang Liu Committed by Thomas Gleixner

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: default avatarJiang 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.comSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 35ef9c94
......@@ -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();
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment