[patch 2/2] [PATCH] fio: fix s390 nop

[ehrhardt@linux.vnet.ibm.com]

[-- Attachment #1: fix-s390-nop.diff --]
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From: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>

When trying to run rate limited fio runs we encountered that the current
definition of a nop uses a privileged instruction which is not even a nop,
but a yield call to the hipervisor.
That leads to a SIGILL as it is privileged.

To solve that issue replace it with a nop, the assembler will take care
of it (likely to become a BCR 0,0)

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
---

[diffstat]
 arch/arch-s390.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

[diff]
--- a/arch/arch-s390.h
+++ b/arch/arch-s390.h
@@ -18,7 +18,7 @@
 #define __NR_sys_vmsplice	309
 #endif
 
-#define nop		asm volatile ("diag 0,0,68" : : : "memory")
+#define nop		asm volatile("nop" : : : "memory")
 #define read_barrier()	asm volatile("bcr 15,0" : : : "memory")
 #define write_barrier()	asm volatile("bcr 15,0" : : : "memory")