Commit 5720aab2 authored Dec 01, 2022 by Heiko Carstens Committed by Alexander Gordeev Dec 06, 2022

s390/nmi: use vector instruction macros instead of byte patterns



Use vector instruction macros instead of byte patterns to increase
readability. The generated code is nearly identical:

- 1e8:  e7 0f 10 00 00 36       vlm     %v0,%v15,0(%r1)
- 1ee:  e7 0f 11 00 0c 36       vlm     %v16,%v31,256(%r1)
+ 1e8:  e7 0f 10 00 30 36       vlm     %v0,%v15,0(%r1),3
+ 1ee:  e7 0f 11 00 3c 36       vlm     %v16,%v31,256(%r1),3

By using the VLM macro the alignment hint is automatically specified
too. Even though from a performance perspective it doesn't matter at
all for the machine check code, this shows yet another benefit when
using the macros.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

parent 706f2ada

arch/s390/kernel/nmi.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -19,7 +19,7 @@
		#include <linux/time.h>
		#include <linux/module.h>
		#include <linux/sched/signal.h>

		#include <linux/kvm_host.h>
		#include <linux/export.h>
		#include <asm/lowcore.h>
		#include <asm/smp.h>
		@@ -31,8 +31,7 @@
		#include <asm/ctl_reg.h>
		#include <asm/asm-offsets.h>
		#include <asm/pai.h>

		#include <linux/kvm_host.h>
		#include <asm/vx-insn.h>

		struct mcck_struct {
		unsigned int kill_task : 1;
		@@ -293,8 +292,8 @@ static int notrace s390_validate_registers(union mci mci, int umode)
		__ctl_load(cr0.val, 0, 0);
		asm volatile(
		" la 1,%0\n"
		" .word 0xe70f,0x1000,0x0036\n" /* vlm 0,15,0(1) */
		" .word 0xe70f,0x1100,0x0c36\n" /* vlm 16,31,256(1) */
		" VLM 0,15,0,1\n"
		" VLM 16,31,256,1\n"
		:
		: "Q" ((struct vx_array )mcesa->vector_save_area)
		: "1");