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-rw-r--r--arch/sparc/include/asm/pil.h31
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/pil.h b/arch/sparc/include/asm/pil.h
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+++ b/arch/sparc/include/asm/pil.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#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==PIL_NORMAL_MAX.
+ *
+ * Finally, in order to handle profiling events even when a
+ * local_irq_disable() is in progress, we only disable up to level 14
+ * interrupts. Profile counter overflow interrupts arrive at level
+ * 15.
+ */
+#define PIL_SMP_CALL_FUNC 1
+#define PIL_SMP_RECEIVE_SIGNAL 2
+#define PIL_SMP_CAPTURE 3
+#define PIL_DEVICE_IRQ 5
+#define PIL_SMP_CALL_FUNC_SNGL 6
+#define PIL_DEFERRED_PCR_WORK 7
+#define PIL_KGDB_CAPTURE 8
+#define PIL_NORMAL_MAX 14
+#define PIL_NMI 15
+
+#endif /* !(_SPARC64_PIL_H) */