Merge branch 'linus' into x86/xen

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/sparc/include/asm/pil.h b/arch/sparc/include/asm/pil.h
new file mode 100644
index 000000000000..71819bb943fc
--- /dev/null
+++ b/arch/sparc/include/asm/pil.h
@@ -0,0 +1,22 @@
+#ifndef _SPARC64_PIL_H
+#define _SPARC64_PIL_H
+
+/* To avoid some locking problems, we hard allocate certain PILs
+ * for SMP cross call messages that must do a etrap/rtrap.
+ *
+ * A local_irq_disable() does not block the cross call delivery, so
+ * when SMP locking is an issue we reschedule the event into a PIL
+ * interrupt which is blocked by local_irq_disable().
+ *
+ * In fact any XCALL which has to etrap/rtrap has a problem because
+ * it is difficult to prevent rtrap from running BH's, and that would
+ * need to be done if the XCALL arrived while %pil==15.
+ */
+#define PIL_SMP_CALL_FUNC       1
+#define PIL_SMP_RECEIVE_SIGNAL  2
+#define PIL_SMP_CAPTURE         3
+#define PIL_SMP_CTX_NEW_VERSION 4
+#define PIL_DEVICE_IRQ          5
+#define PIL_SMP_CALL_FUNC_SNGL  6
+
+#endif /* !(_SPARC64_PIL_H) */