IRQ: allocate CPU masks dynamically

This includes delaying the initialization of dynamically created IRQs
until their actual first use and some further elimination of uses of
struct irq_cfg.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/xen/common/irq.c b/xen/common/irq.c
new file mode 100644
index 0000000000..83761505f0
--- /dev/null
+++ b/xen/common/irq.c
@@ -0,0 +1,28 @@
+#include <xen/config.h>
+#include <xen/irq.h>
+
+int init_one_irq_desc(struct irq_desc *desc)
+{
+    int err;
+
+    if (irq_desc_initialized(desc))
+        return 0;
+
+    if ( !alloc_cpumask_var(&desc->affinity) )
+        return -ENOMEM;
+
+    desc->status = IRQ_DISABLED;
+    desc->handler = &no_irq_type;
+    spin_lock_init(&desc->lock);
+    cpumask_setall(desc->affinity);
+    INIT_LIST_HEAD(&desc->rl_link);
+
+    err = arch_init_one_irq_desc(desc);
+    if ( err )
+    {
+        free_cpumask_var(desc->affinity);
+        desc->handler = NULL;
+    }
+
+    return err;
+}