summaryrefslogtreecommitdiffstats
path: root/include/asm-alpha/hardirq.h
diff options
context:
space:
mode:
authorRalf Baechle <ralf@linux-mips.org>1998-05-07 02:55:41 +0000
committerRalf Baechle <ralf@linux-mips.org>1998-05-07 02:55:41 +0000
commitdcec8a13bf565e47942a1751a9cec21bec5648fe (patch)
tree548b69625b18cc2e88c3e68d0923be546c9ebb03 /include/asm-alpha/hardirq.h
parent2e0f55e79c49509b7ff70ff1a10e1e9e90a3dfd4 (diff)
o Merge with Linux 2.1.99.
o Fix ancient bug in the ELF loader making ldd crash. o Fix ancient bug in the keyboard code for SGI, SNI and Jazz.
Diffstat (limited to 'include/asm-alpha/hardirq.h')
-rw-r--r--include/asm-alpha/hardirq.h60
1 files changed, 59 insertions, 1 deletions
diff --git a/include/asm-alpha/hardirq.h b/include/asm-alpha/hardirq.h
index 733216be9..556e744d2 100644
--- a/include/asm-alpha/hardirq.h
+++ b/include/asm-alpha/hardirq.h
@@ -17,7 +17,65 @@ extern unsigned int local_irq_count[NR_CPUS];
#else
-#error No habla alpha SMP
+/* initially just a straight copy if the i386 code */
+
+#include <asm/atomic.h>
+#include <asm/spinlock.h>
+#include <asm/system.h>
+#include <asm/smp.h>
+
+extern unsigned char global_irq_holder;
+extern spinlock_t global_irq_lock;
+extern atomic_t global_irq_count;
+
+static inline void release_irqlock(int cpu)
+{
+ /* if we didn't own the irq lock, just ignore.. */
+ if (global_irq_holder == (unsigned char) cpu) {
+ global_irq_holder = NO_PROC_ID;
+ spin_unlock(&global_irq_lock);
+ }
+}
+
+/* Ordering of the counter bumps is _deadly_ important. */
+static inline void hardirq_enter(int cpu)
+{
+ ++local_irq_count[cpu];
+ atomic_inc(&global_irq_count);
+}
+
+static inline void hardirq_exit(int cpu)
+{
+ atomic_dec(&global_irq_count);
+ --local_irq_count[cpu];
+}
+
+static inline int hardirq_trylock(int cpu)
+{
+ unsigned long flags;
+ int ret = 1;
+
+ __save_and_cli(flags);
+ if ((atomic_add_return(1, &global_irq_count) != 1) ||
+ (global_irq_lock.lock != 0)) {
+ atomic_dec(&global_irq_count);
+ __restore_flags(flags);
+ ret = 0;
+ } else {
+ ++local_irq_count[cpu];
+ __sti();
+ }
+ return ret;
+}
+
+#define hardirq_endlock(cpu) \
+ do { \
+ __cli(); \
+ hardirq_exit(cpu); \
+ __sti(); \
+ } while (0)
+
+extern void synchronize_irq(void);
#endif /* __SMP__ */
#endif /* _ALPHA_HARDIRQ_H */