bitkeeper revision 1.952 (40c8935a3XSRdQfnx5RoO7XgaggvOQ)

Towards x86_64 support. Merged a bunch of the existing x86_64 stuff
back into a generic 'x86' architecture. Aim is to share as much
as possible between 32- and 64-bit worlds.

1 files changed, 40 insertions, 0 deletions

diff --git a/xen/arch/x86/flushtlb.c b/xen/arch/x86/flushtlb.c
new file mode 100644
index 0000000000..c53f52161c
--- /dev/null
+++ b/xen/arch/x86/flushtlb.c
@@ -0,0 +1,40 @@
+/******************************************************************************
+ * flushtlb.c
+ * 
+ * TLB flushes are timestamped using a global virtual 'clock' which ticks
+ * on any TLB flush on any processor.
+ * 
+ * Copyright (c) 2003, K A Fraser
+ */
+
+#include <xen/config.h>
+#include <xen/sched.h>
+#include <xen/interrupt.h>
+#include <asm/flushtlb.h>
+
+u32 tlbflush_clock;
+u32 tlbflush_time[NR_CPUS];
+
+void tlb_clocktick(void)
+{
+    u32 y, ny;
+
+    /* Tick the clock. 'y' contains the current time after the tick. */
+    ny = tlbflush_clock;
+    do {
+#ifdef CONFIG_SMP
+        if ( unlikely(((y = ny+1) & TLBCLOCK_EPOCH_MASK) == 0) )
+        {
+            raise_softirq(NEW_TLBFLUSH_CLOCK_PERIOD_SOFTIRQ);
+            y = tlbflush_clock;
+            break;
+        }
+#else
+        y = ny+1;
+#endif
+    }
+    while ( unlikely((ny = cmpxchg(&tlbflush_clock, y-1, y)) != y-1) );
+
+    /* Update this CPU's timestamp to new time. */
+    tlbflush_time[smp_processor_id()] = y;
+}