2 files changed, 30 insertions, 9 deletions

diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 5b7e736f3b49..028a2b95936c 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -249,3 +249,32 @@ time_init (void)
          */
         set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec);
 }
+
+#define SMALLUSECS 100
+
+void
+udelay (unsigned long usecs)
+{
+        unsigned long start;
+        unsigned long cycles;
+        unsigned long smallusecs;
+
+        /*
+         * Execute the non-preemptible delay loop (because the ITC might
+         * not be synchronized between CPUS) in relatively short time
+         * chunks, allowing preemption between the chunks.
+         */
+        while (usecs > 0) {
+                smallusecs = (usecs > SMALLUSECS) ? SMALLUSECS : usecs;
+                preempt_disable();
+                cycles = smallusecs*local_cpu_data->cyc_per_usec;
+                start = ia64_get_itc();
+
+                while (ia64_get_itc() - start < cycles)
+                        cpu_relax();
+
+                preempt_enable();
+                usecs -= smallusecs;
+        }
+}
+EXPORT_SYMBOL(udelay);
diff --git a/include/asm-ia64/delay.h b/include/asm-ia64/delay.h
index 57182d6f2b9a..bba702076391 100644
--- a/include/asm-ia64/delay.h
+++ b/include/asm-ia64/delay.h
@@ -84,14 +84,6 @@ __delay (unsigned long loops)
         ia64_delay_loop (loops - 1);
 }
 
-static __inline__ void
-udelay (unsigned long usecs)
-{
-        unsigned long start = ia64_get_itc();
-        unsigned long cycles = usecs*local_cpu_data->cyc_per_usec;
-
-        while (ia64_get_itc() - start < cycles)
-                cpu_relax();
-}
+extern void udelay (unsigned long usecs);
 
 #endif /* _ASM_IA64_DELAY_H */