[PATCH v2] KVM: Optimize kvm_arch_vcpu_ioctl_run function

Tianjia Zhang
2020-04-16T05:11:18Z

In earlier versions of kvm, 'kvm_run' is an independent structure
and is not included in the vcpu structure. At present, 'kvm_run'
is already included in the vcpu structure, so the parameter
'kvm_run' is redundant.

This patch simplify the function definition, removes the extra
'kvm_run' parameter, and extract it from the 'kvm_vcpu' structure
if necessary.

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
---

v2 change:
remove 'kvm_run' parameter and extract it from 'kvm_vcpu'

arch/mips/kvm/mips.c | 3 ++-
arch/powerpc/kvm/powerpc.c | 3 ++-
arch/s390/kvm/kvm-s390.c | 3 ++-
arch/x86/kvm/x86.c | 11 ++++++-----
include/linux/kvm_host.h | 2 +-
virt/kvm/arm/arm.c | 6 +++---
virt/kvm/kvm_main.c | 2 +-
7 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 8f05dd0a0f4e..ec24adf4857e 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -439,8 +439,9 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
return -ENOIOCTLCMD;
}

-int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
+ struct kvm_run *run = vcpu->run;
int r = -EINTR;

vcpu_load(vcpu);
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index e15166b0a16d..7e24691e138a 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -1764,8 +1764,9 @@ int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg)
return r;
}

-int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
+ struct kvm_run *run = vcpu->run;
int r;

vcpu_load(vcpu);
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 19a81024fe16..443af3ead739 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4333,8 +4333,9 @@ static void store_regs(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
store_regs_fmt2(vcpu, kvm_run);
}

-int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
+ struct kvm_run *kvm_run = vcpu->run;
int rc;

if (kvm_run->immediate_exit)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3bf2ecafd027..a0338e86c90f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8707,8 +8707,9 @@ static void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
trace_kvm_fpu(0);
}

-int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
+ struct kvm_run *kvm_run = vcpu->run;
int r;

vcpu_load(vcpu);
@@ -8726,18 +8727,18 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
r = -EAGAIN;
if (signal_pending(current)) {
r = -EINTR;
- vcpu->run->exit_reason = KVM_EXIT_INTR;
+ kvm_run->exit_reason = KVM_EXIT_INTR;
++vcpu->stat.signal_exits;
}
goto out;
}

- if (vcpu->run->kvm_valid_regs & ~KVM_SYNC_X86_VALID_FIELDS) {
+ if (kvm_run->kvm_valid_regs & ~KVM_SYNC_X86_VALID_FIELDS) {
r = -EINVAL;
goto out;
}

- if (vcpu->run->kvm_dirty_regs) {
+ if (kvm_run->kvm_dirty_regs) {
r = sync_regs(vcpu);
if (r != 0)
goto out;
@@ -8767,7 +8768,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)

out:
kvm_put_guest_fpu(vcpu);
- if (vcpu->run->kvm_valid_regs)
+ if (kvm_run->kvm_valid_regs)
store_regs(vcpu);
post_kvm_run_save(vcpu);
kvm_sigset_deactivate(vcpu);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 6d58beb65454..1e17ef719595 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -866,7 +866,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state);
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
struct kvm_guest_debug *dbg);
-int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run);
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu);

int kvm_arch_init(void *opaque);
void kvm_arch_exit(void);
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 48d0ec44ad77..f5390ac2165b 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -639,7 +639,6 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu)
/**
* kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
* @vcpu: The VCPU pointer
- * @run: The kvm_run structure pointer used for userspace state exchange
*
* This function is called through the VCPU_RUN ioctl called from user space. It
* will execute VM code in a loop until the time slice for the process is used
@@ -647,8 +646,9 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu)
* return with return value 0 and with the kvm_run structure filled in with the
* required data for the requested emulation.
*/
-int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
+ struct kvm_run *run = vcpu->run;
int ret;

if (unlikely(!kvm_vcpu_initialized(vcpu)))
@@ -659,7 +659,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
return ret;

if (run->exit_reason == KVM_EXIT_MMIO) {
- ret = kvm_handle_mmio_return(vcpu, vcpu->run);
+ ret = kvm_handle_mmio_return(vcpu, run);
if (ret)
return ret;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 74bdb7bf3295..e18faea89146 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3135,7 +3135,7 @@ static long kvm_vcpu_ioctl(struct file *filp,
synchronize_rcu();
put_pid(oldpid);
}
- r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
+ r = kvm_arch_vcpu_ioctl_run(vcpu);
trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
break;
}
--
2.17.1