[for-next,v3,05/12] x86/domain: factor out pv_vcpu_initialise

Commit Message

Wei Liu April 26, 2017, 3:54 p.m. UTC

Move PV specific vcpu initialisation code to said function, but leave
the only line needed by idle domain in vcpu_initialise.

Use pv_vcpu_destroy in error path to simplify code. It is safe to do so
because the destruction function accepts partially initialised vcpu
struct.

Signed-off-by: Wei Liu <[e-mail]>
---
v3: address Jan's comments

Cc: Jan Beulich <[e-mail]>
Cc: Andrew Cooper <[e-mail]>
---
 xen/arch/x86/domain.c | 99 ++++++++++++++++++++++++++-------------------------
 1 file changed, 50 insertions(+), 49 deletions(-)

Comments

Jan Beulich April 28, 2017, 8:41 a.m. UTC | #1

>>> On 26.04.17 at 17:54, <[e-mail]> wrote:
> Move PV specific vcpu initialisation code to said function, but leave
> the only line needed by idle domain in vcpu_initialise.
> 
> Use pv_vcpu_destroy in error path to simplify code. It is safe to do so
> because the destruction function accepts partially initialised vcpu
> struct.
> 
> Signed-off-by: Wei Liu <[e-mail]>

Reviewed-by: Jan Beulich <[e-mail]>

Patch

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index bdf51785e6..cea80803a5 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -400,6 +400,50 @@  static void pv_destroy_gdt_ldt_l1tab(struct vcpu *v)
                               1U << GDT_LDT_VCPU_SHIFT);
 }
 
+static void pv_vcpu_destroy(struct vcpu *v);
+static int pv_vcpu_initialise(struct vcpu *v)
+{
+    struct domain *d = v->domain;
+    int rc;
+
+    ASSERT(!is_idle_domain(d));
+
+    spin_lock_init(&v->arch.pv_vcpu.shadow_ldt_lock);
+
+    rc = pv_create_gdt_ldt_l1tab(v);
+    if ( rc )
+        return rc;
+
+    BUILD_BUG_ON(NR_VECTORS * sizeof(*v->arch.pv_vcpu.trap_ctxt) >
+                 PAGE_SIZE);
+    v->arch.pv_vcpu.trap_ctxt = xzalloc_array(struct trap_info,
+                                              NR_VECTORS);
+    if ( !v->arch.pv_vcpu.trap_ctxt )
+    {
+        rc = -ENOMEM;
+        goto done;
+    }
+
+    /* PV guests by default have a 100Hz ticker. */
+    v->periodic_period = MILLISECS(10);
+
+    v->arch.pv_vcpu.ctrlreg[4] = real_cr4_to_pv_guest_cr4(mmu_cr4_features);
+
+    if ( is_pv_32bit_domain(d) )
+    {
+        if ( (rc = setup_compat_arg_xlat(v)) )
+            goto done;
+
+        if ( (rc = setup_compat_l4(v)) )
+            goto done;
+    }
+
+ done:
+    if ( rc )
+        pv_vcpu_destroy(v);
+    return rc;
+}
+
 int vcpu_initialise(struct vcpu *v)
 {
     struct domain *d = v->domain;
@@ -426,61 +470,18 @@  int vcpu_initialise(struct vcpu *v)
     spin_lock_init(&v->arch.vpmu.vpmu_lock);
 
     if ( is_hvm_domain(d) )
-    {
         rc = hvm_vcpu_initialise(v);
-        goto done;
-    }
-
-
-    spin_lock_init(&v->arch.pv_vcpu.shadow_ldt_lock);
-
-    if ( !is_idle_domain(d) )
-    {
-        rc = pv_create_gdt_ldt_l1tab(v);
-        if ( rc )
-            goto done;
-
-        BUILD_BUG_ON(NR_VECTORS * sizeof(*v->arch.pv_vcpu.trap_ctxt) >
-                     PAGE_SIZE);
-        v->arch.pv_vcpu.trap_ctxt = xzalloc_array(struct trap_info,
-                                                  NR_VECTORS);
-        if ( !v->arch.pv_vcpu.trap_ctxt )
-        {
-            pv_destroy_gdt_ldt_l1tab(v);
-            rc = -ENOMEM;
-            goto done;
-        }
-
-        /* PV guests by default have a 100Hz ticker. */
-        v->periodic_period = MILLISECS(10);
-    }
+    else if ( !is_idle_domain(d) )
+        rc = pv_vcpu_initialise(v);
     else
-        v->arch.cr3 = __pa(idle_pg_table);
-
-    v->arch.pv_vcpu.ctrlreg[4] = real_cr4_to_pv_guest_cr4(mmu_cr4_features);
-
-    if ( is_pv_32bit_domain(d) )
     {
-        if ( (rc = setup_compat_arg_xlat(v)) )
-            goto done;
-
-        if ( (rc = setup_compat_l4(v)) )
-        {
-            free_compat_arg_xlat(v);
-            goto done;
-        }
+        /* Idle domain */
+        v->arch.cr3 = __pa(idle_pg_table);
+        rc = 0;
     }
- done:
+
     if ( rc )
-    {
         vcpu_destroy_fpu(v);
-
-        if ( is_pv_domain(d) )
-        {
-            pv_destroy_gdt_ldt_l1tab(v);
-            xfree(v->arch.pv_vcpu.trap_ctxt);
-        }
-    }
     else if ( !is_idle_domain(v->domain) )
         vpmu_initialise(v);