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KVM: s390: use switch vs jump table in intercept.c 

Instead of having huge jump tables for function selection,
let's use normal switch/case statements for the instruction
handlers in intercept.c We can now also get rid of
intercept_handler_t.

This allows the compiler to make the right decision depending
on the situation (e.g. avoid jump-tables for thunks).

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
hifive-unleashed-5.1
Christian Borntraeger 2018-02-06 10:19:28 +00:00
parent 6db4263fec
commit cb7485da3e
2 changed files with 29 additions and 24 deletions
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51
arch/s390/kvm/intercept.c
View File

@ -22,22 +22,6 @@
#include "trace.h"
#include "trace-s390.h"
static const intercept_handler_t instruction_handlers[256] = {
[0x01] = kvm_s390_handle_01,
[0x82] = kvm_s390_handle_lpsw,
[0x83] = kvm_s390_handle_diag,
[0xaa] = kvm_s390_handle_aa,
[0xae] = kvm_s390_handle_sigp,
[0xb2] = kvm_s390_handle_b2,
[0xb6] = kvm_s390_handle_stctl,
[0xb7] = kvm_s390_handle_lctl,
[0xb9] = kvm_s390_handle_b9,
[0xe3] = kvm_s390_handle_e3,
[0xe5] = kvm_s390_handle_e5,
[0xeb] = kvm_s390_handle_eb,
};
u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu)
{
struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
@ -129,16 +113,39 @@ static int handle_validity(struct kvm_vcpu *vcpu)
static int handle_instruction(struct kvm_vcpu *vcpu)
{
intercept_handler_t handler;
vcpu->stat.exit_instruction++;
trace_kvm_s390_intercept_instruction(vcpu,
vcpu->arch.sie_block->ipa,
vcpu->arch.sie_block->ipb);
handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8];
if (handler)
return handler(vcpu);
return -EOPNOTSUPP;
switch (vcpu->arch.sie_block->ipa >> 8) {
case 0x01:
return kvm_s390_handle_01(vcpu);
case 0x82:
return kvm_s390_handle_lpsw(vcpu);
case 0x83:
return kvm_s390_handle_diag(vcpu);
case 0xaa:
return kvm_s390_handle_aa(vcpu);
case 0xae:
return kvm_s390_handle_sigp(vcpu);
case 0xb2:
return kvm_s390_handle_b2(vcpu);
case 0xb6:
return kvm_s390_handle_stctl(vcpu);
case 0xb7:
return kvm_s390_handle_lctl(vcpu);
case 0xb9:
return kvm_s390_handle_b9(vcpu);
case 0xe3:
return kvm_s390_handle_e3(vcpu);
case 0xe5:
return kvm_s390_handle_e5(vcpu);
case 0xeb:
return kvm_s390_handle_eb(vcpu);
default:
return -EOPNOTSUPP;
}
}
static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu)

2
arch/s390/kvm/kvm-s390.h
View File

@ -19,8 +19,6 @@
#include <asm/processor.h>
#include <asm/sclp.h>
typedef int (*intercept_handler_t)(struct kvm_vcpu *vcpu);
/* Transactional Memory Execution related macros */
#define IS_TE_ENABLED(vcpu) ((vcpu->arch.sie_block->ecb & ECB_TE))
#define TDB_FORMAT1 1