* instead of just grabbing them. Thus setups with different IRQ numbers
* shouldn't result in any weird surprises, and installing new handlers
* should be easier.
+ *
+ * Copyright (C) Ashok Raj<ashok.raj@intel.com>, Intel Corporation 2004
+ *
+ * 4/14/2004: Added code to handle cpu migration and do safe irq
+ * migration without lossing interrupts for iosapic
+ * architecture.
*/
/*
#include <linux/timex.h>
#include <linux/slab.h>
#include <linux/random.h>
+#include <linux/cpu.h>
#include <linux/ctype.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
+#include <linux/notifier.h>
#include <asm/atomic.h>
+#include <asm/cpu.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/uaccess.h>
#include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
#include <asm/delay.h>
#include <asm/irq.h>
-
/*
* Linux has a controller-independent x86 interrupt architecture.
* every controller has a 'controller-template', that is used
}
};
+/*
+ * This is updated when the user sets irq affinity via /proc
+ */
+cpumask_t __cacheline_aligned pending_irq_cpumask[NR_IRQS];
+
#ifdef CONFIG_IA64_GENERIC
irq_desc_t * __ia64_irq_desc (unsigned int irq)
{
static int irq_affinity_read_proc (char *page, char **start, off_t off,
int count, int *eof, void *data)
{
- int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]);
+ int len = sprintf(page, "%s", irq_redir[(long)data] ? "r " : "");
+
+ len += cpumask_scnprintf(page+len, count, irq_affinity[(long)data]);
if (count - len < 2)
return -EINVAL;
len += sprintf(page + len, "\n");
int rlen;
int prelen;
irq_desc_t *desc = irq_descp(irq);
+ unsigned long flags;
if (!desc->handler->set_affinity)
return -EIO;
if (cpus_empty(tmp))
return -EINVAL;
- desc->handler->set_affinity(irq, new_value);
+ spin_lock_irqsave(&desc->lock, flags);
+ pending_irq_cpumask[irq] = new_value;
+ spin_unlock_irqrestore(&desc->lock, flags);
+
return full_count;
}
#endif /* CONFIG_SMP */
+#ifdef CONFIG_HOTPLUG_CPU
+unsigned int vectors_in_migration[NR_IRQS];
+
+/*
+ * Since cpu_online_map is already updated, we just need to check for
+ * affinity that has zeros
+ */
+static void migrate_irqs(void)
+{
+ cpumask_t mask;
+ irq_desc_t *desc;
+ int irq, new_cpu;
+
+ for (irq=0; irq < NR_IRQS; irq++) {
+ desc = irq_descp(irq);
+
+ /*
+ * No handling for now.
+ * TBD: Implement a disable function so we can now
+ * tell CPU not to respond to these local intr sources.
+ * such as ITV,CPEI,MCA etc.
+ */
+ if (desc->status == IRQ_PER_CPU)
+ continue;
+
+ cpus_and(mask, irq_affinity[irq], cpu_online_map);
+ if (any_online_cpu(mask) == NR_CPUS) {
+ /*
+ * Save it for phase 2 processing
+ */
+ vectors_in_migration[irq] = irq;
+
+ new_cpu = any_online_cpu(cpu_online_map);
+ mask = cpumask_of_cpu(new_cpu);
+
+ /*
+ * Al three are essential, currently WARN_ON.. maybe panic?
+ */
+ if (desc->handler && desc->handler->disable &&
+ desc->handler->enable && desc->handler->set_affinity) {
+ desc->handler->disable(irq);
+ desc->handler->set_affinity(irq, mask);
+ desc->handler->enable(irq);
+ } else {
+ WARN_ON((!(desc->handler) || !(desc->handler->disable) ||
+ !(desc->handler->enable) ||
+ !(desc->handler->set_affinity)));
+ }
+ }
+ }
+}
+
+void fixup_irqs(void)
+{
+ unsigned int irq;
+ extern void ia64_process_pending_intr(void);
+
+ ia64_set_itv(1<<16);
+ /*
+ * Phase 1: Locate irq's bound to this cpu and
+ * relocate them for cpu removal.
+ */
+ migrate_irqs();
+
+ /*
+ * Phase 2: Perform interrupt processing for all entries reported in
+ * local APIC.
+ */
+ ia64_process_pending_intr();
+
+ /*
+ * Phase 3: Now handle any interrupts not captured in local APIC.
+ * This is to account for cases that device interrupted during the time the
+ * rte was being disabled and re-programmed.
+ */
+ for (irq=0; irq < NR_IRQS; irq++) {
+ if (vectors_in_migration[irq]) {
+ vectors_in_migration[irq]=0;
+ do_IRQ(irq, NULL);
+ }
+ }
+
+ /*
+ * Now let processor die. We do irq disable and max_xtp() to
+ * ensure there is no more interrupts routed to this processor.
+ * But the local timer interrupt can have 1 pending which we
+ * take care in timer_interrupt().
+ */
+ max_xtp();
+ local_irq_disable();
+}
+#endif
+
static int prof_cpu_mask_read_proc (char *page, char **start, off_t off,
int count, int *eof, void *data)
{