fedora core 2.6.10-1.12-FC2

[linux-2.6.git] / include / linux / hardirq.h

diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 7e1aad3..eae45cc 100644 (file)
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -5,6 +5,40 @@
 #include <linux/smp_lock.h>
 #include <asm/hardirq.h>
 
+/*
+ * We put the hardirq and softirq counter into the preemption
+ * counter. The bitmask has the following meaning:
+ *
+ * - bits 0-7 are the preemption count (max preemption depth: 256)
+ * - bits 8-15 are the softirq count (max # of softirqs: 256)
+ *
+ * The hardirq count can be overridden per architecture, the default is:
+ *
+ * - bits 16-27 are the hardirq count (max # of hardirqs: 4096)
+ * - ( bit 28 is the PREEMPT_ACTIVE flag. )
+ *
+ * PREEMPT_MASK: 0x000000ff
+ * SOFTIRQ_MASK: 0x0000ff00
+ * HARDIRQ_MASK: 0x0fff0000
+ */
+#define PREEMPT_BITS   8
+#define SOFTIRQ_BITS   8
+
+#ifndef HARDIRQ_BITS
+#define HARDIRQ_BITS   12
+/*
+ * The hardirq mask has to be large enough to have space for potentially
+ * all IRQ sources in the system nesting on a single CPU.
+ */
+#if (1 << HARDIRQ_BITS) < NR_IRQS
+# error HARDIRQ_BITS is too low!
+#endif
+#endif
+
+#define PREEMPT_SHIFT  0
+#define SOFTIRQ_SHIFT  (PREEMPT_SHIFT + PREEMPT_BITS)
+#define HARDIRQ_SHIFT  (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
+
 #define __IRQ_MASK(x)  ((1UL << (x))-1)
 
 #define PREEMPT_MASK   (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
@@ -43,4 +77,12 @@ extern void synchronize_irq(unsigned int irq);
 # define synchronize_irq(irq)  barrier()
 #endif
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+#define nmi_enter()            (preempt_count() += HARDIRQ_OFFSET)
+#define nmi_exit()             (preempt_count() -= HARDIRQ_OFFSET)
+
+#define irq_enter()            (preempt_count() += HARDIRQ_OFFSET)
+extern void irq_exit(void);
+#endif
+
 #endif /* LINUX_HARDIRQ_H */