X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=include%2Flinux%2Fhardirq.h;h=7803014f3a11bae4f353e7b042c0e1835997c7be;hb=9f8b17e643fe6aa505629658445849397bda4e4f;hp=114ae583cca9a28480ba684c342a54b97bf46686;hpb=0c97f524fc16004602f97ba19c36acdcc0fb9688;p=linux-2.6-omap-h63xx.git

diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 114ae583cca..7803014f3a1 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -3,6 +3,7 @@
 
 #include <linux/preempt.h>
 #include <linux/smp_lock.h>
+#include <linux/lockdep.h>
 #include <asm/hardirq.h>
 #include <asm/system.h>
 
@@ -27,11 +28,16 @@
 
 #ifndef HARDIRQ_BITS
 #define HARDIRQ_BITS	12
+
+#ifndef MAX_HARDIRQS_PER_CPU
+#define MAX_HARDIRQS_PER_CPU NR_IRQS
+#endif
+
 /*
  * 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
+#if (1 << HARDIRQ_BITS) < MAX_HARDIRQS_PER_CPU
 # error HARDIRQ_BITS is too low!
 #endif
 #endif
@@ -86,9 +92,6 @@ extern void synchronize_irq(unsigned int irq);
 # define synchronize_irq(irq)	barrier()
 #endif
 
-#define nmi_enter()		irq_enter()
-#define nmi_exit()		sub_preempt_count(HARDIRQ_OFFSET)
-
 struct task_struct;
 
 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
@@ -97,12 +100,40 @@ static inline void account_system_vtime(struct task_struct *tsk)
 }
 #endif
 
-#define irq_enter()					\
+/*
+ * It is safe to do non-atomic ops on ->hardirq_context,
+ * because NMI handlers may not preempt and the ops are
+ * always balanced, so the interrupted value of ->hardirq_context
+ * will always be restored.
+ */
+#define __irq_enter()					\
 	do {						\
 		account_system_vtime(current);		\
 		add_preempt_count(HARDIRQ_OFFSET);	\
+		trace_hardirq_enter();			\
+	} while (0)
+
+/*
+ * Enter irq context (on NO_HZ, update jiffies):
+ */
+extern void irq_enter(void);
+
+/*
+ * Exit irq context without processing softirqs:
+ */
+#define __irq_exit()					\
+	do {						\
+		trace_hardirq_exit();			\
+		account_system_vtime(current);		\
+		sub_preempt_count(HARDIRQ_OFFSET);	\
 	} while (0)
 
+/*
+ * Exit irq context and process softirqs if needed:
+ */
 extern void irq_exit(void);
 
+#define nmi_enter()		do { lockdep_off(); __irq_enter(); } while (0)
+#define nmi_exit()		do { __irq_exit(); lockdep_on(); } while (0)
+
 #endif /* LINUX_HARDIRQ_H */