[SRU][B][D][Patch 2/2] s390: add alignment hints to vector load and store

frank.heimes at canonical.com frank.heimes at canonical.com
Mon Jul 22 18:24:34 UTC 2019


From: Martin Schwidefsky <schwidefsky at de.ibm.com>

BugLink: https://bugs.launchpad.net/bugs/1836857

The z14 introduced alignment hints to increase the performance of
vector loads and stores. The kernel uses an implicit alignmenet
of 8 bytes for the vector registers, set the alignment hint to 3.

Reviewed-by: Christian Borntraeger <borntraeger at de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky at de.ibm.com>
(cherry picked from commit 142c52d7bce45d335f48d53fdbf428bb15cf3924)
Signed-off-by: Frank Heimes <frank.heimes at canonical.com>
---
 arch/s390/include/asm/vx-insn.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/s390/include/asm/vx-insn.h b/arch/s390/include/asm/vx-insn.h
index 266a723..0c05a67 100644
--- a/arch/s390/include/asm/vx-insn.h
+++ b/arch/s390/include/asm/vx-insn.h
@@ -363,23 +363,23 @@
 .endm
 
 /* VECTOR LOAD MULTIPLE */
-.macro	VLM	vfrom, vto, disp, base
+.macro	VLM	vfrom, vto, disp, base, hint=3
 	VX_NUM	v1, \vfrom
 	VX_NUM	v3, \vto
 	GR_NUM	b2, \base	    /* Base register */
 	.word	0xE700 | ((v1&15) << 4) | (v3&15)
 	.word	(b2 << 12) | (\disp)
-	MRXBOPC	0, 0x36, v1, v3
+	MRXBOPC	\hint, 0x36, v1, v3
 .endm
 
 /* VECTOR STORE MULTIPLE */
-.macro	VSTM	vfrom, vto, disp, base
+.macro	VSTM	vfrom, vto, disp, base, hint=3
 	VX_NUM	v1, \vfrom
 	VX_NUM	v3, \vto
 	GR_NUM	b2, \base	    /* Base register */
 	.word	0xE700 | ((v1&15) << 4) | (v3&15)
 	.word	(b2 << 12) | (\disp)
-	MRXBOPC	0, 0x3E, v1, v3
+	MRXBOPC	\hint, 0x3E, v1, v3
 .endm
 
 /* VECTOR PERMUTE */
-- 
2.7.4




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