X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-powerpc%2Fdelay.h;h=f9200a65c632b9421d02b16106feded2eb3eb4eb;hb=refs%2Fheads%2Fvserver;hp=057a6095547483e36f96b3ba243ae79a13b5fd36;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/include/asm-powerpc/delay.h b/include/asm-powerpc/delay.h
index 057a60955..f9200a65c 100644
--- a/include/asm-powerpc/delay.h
+++ b/include/asm-powerpc/delay.h
@@ -17,5 +17,18 @@
 extern void __delay(unsigned long loops);
 extern void udelay(unsigned long usecs);
 
+/*
+ * On shared processor machines the generic implementation of mdelay can
+ * result in large errors. While each iteration of the loop inside mdelay
+ * is supposed to take 1ms, the hypervisor could sleep our partition for
+ * longer (eg 10ms). With the right timing these errors can add up.
+ *
+ * Since there is no 32bit overflow issue on 64bit kernels, just call
+ * udelay directly.
+ */
+#ifdef CONFIG_PPC64
+#define mdelay(n)	udelay((n) * 1000)
+#endif
+
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_DELAY_H */