[PATCH v4 02/28] x86/xstate: drop xstate_offsets[] and xstate_sizes[]

[Jan Beulich <jbeulich@xxxxxxxx>]

They're redundant with respective fields from the raw CPUID policy; no
need to keep two copies of the same data.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
v4: Re-base.

--- a/xen/arch/x86/include/asm/xstate.h
+++ b/xen/arch/x86/include/asm/xstate.h
@@ -45,8 +45,9 @@ extern uint32_t mxcsr_mask;
 
 extern u64 xfeature_mask;
 extern u64 xstate_align;
-extern unsigned int *xstate_offsets;
-extern unsigned int *xstate_sizes;
+
+#define xstate_offset(n) (raw_cpu_policy.xstate.comp[n].offset)
+#define xstate_size(n)   (raw_cpu_policy.xstate.comp[n].size)
 
 /* extended state save area */
 struct __attribute__((aligned (64))) xsave_struct
--- a/xen/arch/x86/xstate.c
+++ b/xen/arch/x86/xstate.c
@@ -28,8 +28,6 @@ static u32 __read_mostly xsave_cntxt_siz
 /* A 64-bit bitmask of the XSAVE/XRSTOR features supported by processor. */
 u64 __read_mostly xfeature_mask;
 
-unsigned int *__read_mostly xstate_offsets;
-unsigned int *__read_mostly xstate_sizes;
 u64 __read_mostly xstate_align;
 static unsigned int __read_mostly xstate_features;
 
@@ -103,34 +101,18 @@ static int setup_xstate_features(bool bs
     unsigned int leaf, eax, ebx, ecx, edx;
 
     if ( bsp )
-    {
         xstate_features = flsl(xfeature_mask);
-        xstate_offsets = xzalloc_array(unsigned int, xstate_features);
-        if ( !xstate_offsets )
-            return -ENOMEM;
-
-        xstate_sizes = xzalloc_array(unsigned int, xstate_features);
-        if ( !xstate_sizes )
-            return -ENOMEM;
-    }
 
     for ( leaf = 2; leaf < xstate_features; leaf++ )
     {
-        if ( bsp )
-        {
-            cpuid_count(XSTATE_CPUID, leaf, &xstate_sizes[leaf],
-                        &xstate_offsets[leaf], &ecx, &edx);
-            if ( ecx & XSTATE_ALIGN64 )
-                __set_bit(leaf, &xstate_align);
-        }
+        cpuid_count(0xd, leaf, &eax, &ebx, &ecx, &edx);
+        BUG_ON(eax != xstate_size(leaf));
+        BUG_ON(ebx != xstate_offset(leaf));
+
+        if ( bsp && (ecx & XSTATE_ALIGN64) )
+            __set_bit(leaf, &xstate_align);
         else
-        {
-            cpuid_count(XSTATE_CPUID, leaf, &eax,
-                        &ebx, &ecx, &edx);
-            BUG_ON(eax != xstate_sizes[leaf]);
-            BUG_ON(ebx != xstate_offsets[leaf]);
             BUG_ON(!(ecx & XSTATE_ALIGN64) != !test_bit(leaf, &xstate_align));
-        }
     }
 
     return 0;
@@ -160,7 +142,7 @@ static void setup_xstate_comp(uint16_t *
             if ( test_bit(i, &xstate_align) )
                 offset = ROUNDUP(offset, 64);
             comp_offsets[i] = offset;
-            offset += xstate_sizes[i];
+            offset += xstate_size(i);
         }
     }
     ASSERT(offset <= xsave_cntxt_size);
@@ -223,10 +205,10 @@ void expand_xsave_states(const struct vc
          * comp_offsets[] information, something is very broken.
          */
         BUG_ON(!comp_offsets[index]);
-        BUG_ON((xstate_offsets[index] + xstate_sizes[index]) > size);
+        BUG_ON((xstate_offset(index) + xstate_size(index)) > size);
 
-        memcpy(dest + xstate_offsets[index], src + comp_offsets[index],
-               xstate_sizes[index]);
+        memcpy(dest + xstate_offset(index), src + comp_offsets[index],
+               xstate_size(index));
 
         valid &= ~feature;
     }
@@ -292,10 +274,10 @@ void compress_xsave_states(struct vcpu *
          * comp_offset[] information, something is very broken.
          */
         BUG_ON(!comp_offsets[index]);
-        BUG_ON((xstate_offsets[index] + xstate_sizes[index]) > size);
+        BUG_ON((xstate_offset(index) + xstate_size(index)) > size);
 
-        memcpy(dest + comp_offsets[index], src + xstate_offsets[index],
-               xstate_sizes[index]);
+        memcpy(dest + comp_offsets[index], src + xstate_offset(index),
+               xstate_size(index));
 
         valid &= ~feature;
     }
@@ -538,8 +520,8 @@ int xstate_alloc_save_area(struct vcpu *
         unsigned int i;
 
         for ( size = 0, i = 2; i < xstate_features; ++i )
-            if ( size < xstate_sizes[i] )
-                size = xstate_sizes[i];
+            if ( size < xstate_size(i) )
+                size = xstate_size(i);
         size += XSTATE_AREA_MIN_SIZE;
     }
 
@@ -592,9 +574,9 @@ int xstate_update_save_area(struct vcpu
     for ( size = old = XSTATE_AREA_MIN_SIZE, i = 2; i < xstate_features; ++i )
     {
         if ( xcr0_max & (1ul << i) )
-            size = max(size, xstate_offsets[i] + xstate_sizes[i]);
+            size = max(size, xstate_offset(i) + xstate_size(i));
         if ( v->arch.xcr0_accum & (1ul << i) )
-            old = max(old, xstate_offsets[i] + xstate_sizes[i]);
+            old = max(old, xstate_offset(i) + xstate_size(i));
     }
 
     save_area = _xvrealloc(v->arch.xsave_area, size, __alignof(*save_area));
@@ -1082,7 +1064,7 @@ uint64_t read_bndcfgu(void)
               : "=m" (*xstate)
               : "a" (X86_XCR0_BNDCSR), "d" (0), "D" (xstate) );
 
-        bndcsr = (void *)xstate + xstate_offsets[ilog2(X86_XCR0_BNDCSR)];
+        bndcsr = (void *)xstate + xstate_offset(ilog2(X86_XCR0_BNDCSR));
     }
 
     if ( cr0 & X86_CR0_TS )