[PATCH v4 08/41] powerpc/book3s64/pkeys: Convert execute key support to static key

@@ -13,13 +13,13 @@
 #include <linux/of_device.h>
 
 DEFINE_STATIC_KEY_TRUE(pkey_disabled);
+DEFINE_STATIC_KEY_FALSE(execute_pkey_disabled);
 int  pkeys_total;		/* Total pkeys as per device tree */
 u32  initial_allocation_mask;   /* Bits set for the initially allocated keys */
 /*
  *  Keys marked in the reservation list cannot be allocated by  userspace
  */
 u32  reserved_allocation_mask;
-static bool pkey_execute_disable_supported;
 static u64 default_amr;
 static u64 default_iamr;
 /* Allow all keys to be modified by default */

@@ -116,9 +116,7 @@ static int pkey_initialize(void)
 	 * execute_disable support. Instead we use a PVR check.
 	 */
 	if (pvr_version_is(PVR_POWER7) || pvr_version_is(PVR_POWER7p))
-		pkey_execute_disable_supported = false;
-	else
-		pkey_execute_disable_supported = true;
+		static_branch_enable(&execute_pkey_disabled);
 
 #ifdef CONFIG_PPC_4K_PAGES
 	/*

@@ -214,7 +212,7 @@ static inline void write_amr(u64 value)
 
 static inline u64 read_iamr(void)
 {
-	if (!likely(pkey_execute_disable_supported))
+	if (static_branch_unlikely(&execute_pkey_disabled))
 		return 0x0UL;
 
 	return mfspr(SPRN_IAMR);

@@ -222,7 +220,7 @@ static inline u64 read_iamr(void)
 
 static inline void write_iamr(u64 value)
 {
-	if (!likely(pkey_execute_disable_supported))
+	if (static_branch_unlikely(&execute_pkey_disabled))
 		return;
 
 	mtspr(SPRN_IAMR, value);

@@ -282,7 +280,7 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 		return -EINVAL;
 
 	if (init_val & PKEY_DISABLE_EXECUTE) {
-		if (!pkey_execute_disable_supported)
+		if (static_branch_unlikely(&execute_pkey_disabled))
 			return -EINVAL;
 		new_iamr_bits |= IAMR_EX_BIT;
 	}