From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Wed, 5 Jun 2013 07:25:34 +0000 (+0200)
Subject: s390/pgtable: make pgste lock an explicit barrier
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a8f6e7f7953d1baa05a346bf7cee44f1d022c63d;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git

s390/pgtable: make pgste lock an explicit barrier

Getting and Releasing the pgste lock has lock semantics. Make the
code an explicit barrier.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index f9a0a70dc936..e8b6e5b8932c 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -623,7 +623,7 @@ static inline pgste_t pgste_get_lock(pte_t *ptep)
 		"	csg	%0,%1,%2\n"
 		"	jl	0b\n"
 		: "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE])
-		: "Q" (ptep[PTRS_PER_PTE]) : "cc");
+		: "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory");
 #endif
 	return __pgste(new);
 }
@@ -635,7 +635,8 @@ static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
 		"	nihh	%1,0xff7f\n"	/* clear RCP_PCL_BIT */
 		"	stg	%1,%0\n"
 		: "=Q" (ptep[PTRS_PER_PTE])
-		: "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE]) : "cc");
+		: "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE])
+		: "cc", "memory");
 	preempt_enable();
 #endif
 }