xen: Infrastructure to allow irqs to share vector maps

Laying the groundwork for per-device vector maps.  This generic
code allows any irq to point to a vector map; all irqs sharing the
same vector map will avoid sharing vectors.

Signed-off-by: George Dunlap <george.dunlap@eu.citrix.com>

diff --git a/xen/arch/x86/io_apic.c b/xen/arch/x86/io_apic.c
index 908915a4dbd7f9676bf3f44f55e797ba5fc1d65e..258f341c25c7010d89b7a216399c682c6fc681dc 100644 (file)
--- a/xen/arch/x86/io_apic.c
+++ b/xen/arch/x86/io_apic.c
@@ -449,6 +449,11 @@ fastcall void smp_irq_move_cleanup_interrupt(struct cpu_user_regs *regs)
                  irq, vector, smp_processor_id());
 
         __get_cpu_var(vector_irq)[vector] = -1;
+        if ( cfg->used_vectors )
+        {
+            ASSERT(test_bit(vector, cfg->used_vectors));
+            clear_bit(vector, cfg->used_vectors);
+        }
         cfg->move_cleanup_count--;
 unlock:
         spin_unlock(&desc->lock);

diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index 7c5a8b64048430e98891fb7b9daaca31b1161751..f02ab0c9cffa2862b03724a108cf4bad72d03118 100644 (file)
--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -108,6 +108,8 @@ static int __init __bind_irq_vector(int irq, int vector, cpumask_t cpu_mask)
         per_cpu(vector_irq, cpu)[vector] = irq;
     cfg->vector = vector;
     cfg->cpu_mask = online_mask;
+    if ( cfg->used_vectors )
+        set_bit(vector, cfg->used_vectors);
     irq_status[irq] = IRQ_USED;
     if (IO_APIC_IRQ(irq))
         irq_vector[irq] = vector;
@@ -172,6 +174,7 @@ static void dynamic_irq_cleanup(unsigned int irq)
     desc->depth   = 1;
     desc->msi_desc = NULL;
     desc->handler = &no_irq_type;
+    desc->chip_data->used_vectors=NULL;
     cpus_setall(desc->affinity);
     spin_unlock_irqrestore(&desc->lock, flags);
 
@@ -200,6 +203,9 @@ static void __clear_irq_vector(int irq)
     for_each_cpu_mask(cpu, tmp_mask)
         per_cpu(vector_irq, cpu)[vector] = -1;
 
+    if ( cfg->used_vectors )
+        clear_bit(vector, cfg->used_vectors);
+
     cfg->vector = IRQ_VECTOR_UNASSIGNED;
     cpus_clear(cfg->cpu_mask);
     init_one_irq_status(irq);
@@ -277,6 +283,7 @@ static void __init init_one_irq_cfg(struct irq_cfg *cfg)
     cfg->vector = IRQ_VECTOR_UNASSIGNED;
     cpus_clear(cfg->cpu_mask);
     cpus_clear(cfg->old_cpu_mask);
+    cfg->used_vectors = NULL;
 }
 
 int __init init_irq_data(void)
@@ -402,6 +409,10 @@ next:
         if (test_bit(vector, used_vectors))
             goto next;
 
+        if (cfg->used_vectors
+            && test_bit(vector, cfg->used_vectors) )
+            goto next;
+
         for_each_cpu_mask(new_cpu, tmp_mask)
             if (per_cpu(vector_irq, new_cpu)[vector] != -1)
                 goto next;
@@ -417,6 +428,11 @@ next:
             per_cpu(vector_irq, new_cpu)[vector] = irq;
         cfg->vector = vector;
         cpus_copy(cfg->cpu_mask, tmp_mask);
+        if ( cfg->used_vectors )
+        {
+            ASSERT(!test_bit(vector, cfg->used_vectors));
+            set_bit(vector, cfg->used_vectors);
+        }
 
         irq_status[irq] = IRQ_USED;
             if (IO_APIC_IRQ(irq))

diff --git a/xen/include/asm-x86/irq.h b/xen/include/asm-x86/irq.h
index bf62e8bcc5354158c184df289434c8880fcb2574..da0b2b99d51fd674ea10f4abf91e55513c735298 100644 (file)
--- a/xen/include/asm-x86/irq.h
+++ b/xen/include/asm-x86/irq.h
@@ -24,11 +24,16 @@
 #define irq_to_desc(irq)    (&irq_desc[irq])
 #define irq_cfg(irq)        (&irq_cfg[irq])
 
+typedef struct {
+    DECLARE_BITMAP(_bits,NR_VECTORS);
+} vmask_t;
+
 struct irq_cfg {
         int  vector;
         cpumask_t cpu_mask;
         cpumask_t old_cpu_mask;
         unsigned move_cleanup_count;
+        vmask_t *used_vectors;
         u8 move_in_progress : 1;
 };