[PATCH] fix kirq for clustered apic mode

Dave Hansen
2003-02-16T01:13:40Z

[-- Attachment #1: Type: text/plain, Size: 457 bytes --]

The new kirq patch assumes flat addressing APIC mode where apicid = (1
<< cpu). This isn't true for clustered mode.

- Change name/type of irq_balance_mask. The type of apicid seems to
be int.
- Change instance of (1<<cpu) to cpu_to_logical_apicid()
- Don't use target_cpu_mask, use min_loaded, and convert the real way

Tested on Summit, and plain SMP. Martin Bligh and I figured this out
together, and he agrees.
--
Dave Hansen
haveblue@us.ibm.com

[-- Attachment #2: kirq-apicid-fix-2.5.61-1.patch --]
[-- Type: text/plain, Size: 1946 bytes --]

diff -ru linux-2.5.61-clean/arch/i386/kernel/io_apic.c linux-2.5.61-irqdebug/arch/i386/kernel/io_apic.c
--- linux-2.5.61-clean/arch/i386/kernel/io_apic.c 2003-02-14 17:51:26.000000000 -0600
+++ linux-2.5.61-irqdebug/arch/i386/kernel/io_apic.c 2003-02-15 17:42:51.000000000 -0600
@@ -222,7 +222,7 @@
# endif

extern unsigned long irq_affinity [NR_IRQS];
-unsigned long __cacheline_aligned irq_balance_mask [NR_IRQS];
+int __cacheline_aligned pending_irq_balance_apicid [NR_IRQS];
static int irqbalance_disabled __initdata = 0;
static int physical_balance = 0;

@@ -441,7 +441,7 @@
Dprintk("irq = %d moved to cpu = %d\n", selected_irq, min_loaded);
/* mark for change destination */
spin_lock(&desc->lock);
- irq_balance_mask[selected_irq] = target_cpu_mask;
+ pending_irq_balance_apicid[selected_irq] = cpu_to_logical_apicid(min_loaded);
spin_unlock(&desc->lock);
/* Since we made a change, come back sooner to
* check for more variation.
@@ -500,7 +500,7 @@
if (cpu != new_cpu) {
irq_desc_t *desc = irq_desc + irq;
spin_lock(&desc->lock);
- irq_balance_mask[irq] = cpu_to_logical_apicid(new_cpu);
+ pending_irq_balance_apicid[irq] = cpu_to_logical_apicid(new_cpu);
spin_unlock(&desc->lock);
}
}
@@ -515,7 +515,7 @@

/* push everything to CPU 0 to give us a starting point. */
for (i = 0 ; i < NR_IRQS ; i++)
- irq_balance_mask[i] = 1 << 0;
+ pending_irq_balance_apicid[i] = cpu_to_logical_apicid(0);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
time_remaining = schedule_timeout(time_remaining);
@@ -580,9 +580,9 @@
static inline void move_irq(int irq)
{
/* note - we hold the desc->lock */
- if (unlikely(irq_balance_mask[irq])) {
- set_ioapic_affinity(irq, irq_balance_mask[irq]);
- irq_balance_mask[irq] = 0;
+ if (unlikely(pending_irq_balance_apicid[irq])) {
+ set_ioapic_affinity(irq, pending_irq_balance_apicid[irq]);
+ pending_irq_balance_apicid[irq] = 0;
}
}