5 files changed, 50 insertions, 48 deletions

diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 8a6295c86209..83e4f959ee47 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -21,6 +21,8 @@
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
+#include <linux/cpuidle.h>
+#include <linux/cpufreq.h>
 
 #include <linux/mm.h>
 
@@ -267,18 +269,28 @@ static int __init xen_guest_init(void)
         if (!xen_initial_domain())
                 xenbus_probe(NULL);
 
+        /*
+         * Making sure board specific code will not set up ops for
+         * cpu idle and cpu freq.
+         */
+        disable_cpuidle();
+        disable_cpufreq();
+
         return 0;
 }
 core_initcall(xen_guest_init);
 
 static int __init xen_pm_init(void)
 {
+        if (!xen_domain())
+                return -ENODEV;
+
         pm_power_off = xen_power_off;
         arm_pm_restart = xen_restart;
 
         return 0;
 }
-subsys_initcall(xen_pm_init);
+late_initcall(xen_pm_init);
 
 static irqreturn_t xen_arm_callback(int irq, void *arg)
 {
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 2fc216dfbd9c..fa6ade76ef3f 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1692,7 +1692,6 @@ static int xen_hvm_cpu_notify(struct notifier_block *self, unsigned long action,
         case CPU_UP_PREPARE:
                 xen_vcpu_setup(cpu);
                 if (xen_have_vector_callback) {
-                        xen_init_lock_cpu(cpu);
                         if (xen_feature(XENFEAT_hvm_safe_pvclock))
                                 xen_setup_timer(cpu);
                 }
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 0d4ec35895d4..8b901e8d782d 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -990,10 +990,13 @@ int m2p_remove_override(struct page *page,
                                 printk(KERN_WARNING "m2p_remove_override: "
                                                 "pfn %lx mfn %lx, failed to modify kernel mappings",
                                                 pfn, mfn);
+                                put_balloon_scratch_page();
                                 return -1;
                         }
 
-                        mcs = xen_mc_entry(
+                        xen_mc_batch();
+
+                        mcs = __xen_mc_entry(
                                         sizeof(struct gnttab_unmap_and_replace));
                         unmap_op = mcs.args;
                         unmap_op->host_addr = kmap_op->host_addr;
@@ -1003,12 +1006,11 @@ int m2p_remove_override(struct page *page,
                         MULTI_grant_table_op(mcs.mc,
                                         GNTTABOP_unmap_and_replace, unmap_op, 1);
 
-                        xen_mc_issue(PARAVIRT_LAZY_MMU);
-
                         mcs = __xen_mc_entry(0);
                         MULTI_update_va_mapping(mcs.mc, scratch_page_address,
-                                        pfn_pte(page_to_pfn(get_balloon_scratch_page()),
+                                        pfn_pte(page_to_pfn(scratch_page),
                                         PAGE_KERNEL_RO), 0);
+
                         xen_mc_issue(PARAVIRT_LAZY_MMU);
 
                         kmap_op->host_addr = 0;
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 9235842cd76a..d1e4777b4e75 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -273,12 +273,20 @@ static void __init xen_smp_prepare_boot_cpu(void)
         BUG_ON(smp_processor_id() != 0);
         native_smp_prepare_boot_cpu();
 
-        /* We've switched to the "real" per-cpu gdt, so make sure the
-           old memory can be recycled */
-        make_lowmem_page_readwrite(xen_initial_gdt);
+        if (xen_pv_domain()) {
+                /* We've switched to the "real" per-cpu gdt, so make sure the
+                   old memory can be recycled */
+                make_lowmem_page_readwrite(xen_initial_gdt);
 
-        xen_filter_cpu_maps();
-        xen_setup_vcpu_info_placement();
+                xen_filter_cpu_maps();
+                xen_setup_vcpu_info_placement();
+        }
+        /*
+         * The alternative logic (which patches the unlock/lock) runs before
+         * the smp bootup up code is activated. Hence we need to set this up
+         * the core kernel is being patched. Otherwise we will have only
+         * modules patched but not core code.
+         */
         xen_init_spinlocks();
 }
 
@@ -709,6 +717,15 @@ static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
         WARN_ON(rc);
         if (!rc)
                 rc =  native_cpu_up(cpu, tidle);
+
+        /*
+         * We must initialize the slowpath CPU kicker _after_ the native
+         * path has executed. If we initialized it before none of the
+         * unlocker IPI kicks would reach the booting CPU as the booting
+         * CPU had not set itself 'online' in cpu_online_mask. That mask
+         * is checked when IPIs are sent (on HVM at least).
+         */
+        xen_init_lock_cpu(cpu);
         return rc;
 }
 
@@ -728,4 +745,5 @@ void __init xen_hvm_smp_init(void)
         smp_ops.cpu_die = xen_hvm_cpu_die;
         smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
         smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
+        smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu;
 }
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 0438b9324a72..253f63fceea1 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -81,7 +81,6 @@ static inline void spin_time_accum_blocked(u64 start)
         spinlock_stats.time_blocked += delta;
 }
 #else  /* !CONFIG_XEN_DEBUG_FS */
-#define TIMEOUT                 (1 << 10)
 static inline void add_stats(enum xen_contention_stat var, u32 val)
 {
 }
@@ -96,23 +95,6 @@ static inline void spin_time_accum_blocked(u64 start)
 }
 #endif  /* CONFIG_XEN_DEBUG_FS */
 
-/*
- * Size struct xen_spinlock so it's the same as arch_spinlock_t.
- */
-#if NR_CPUS < 256
-typedef u8 xen_spinners_t;
-# define inc_spinners(xl) \
-        asm(LOCK_PREFIX " incb %0" : "+m" ((xl)->spinners) : : "memory");
-# define dec_spinners(xl) \
-        asm(LOCK_PREFIX " decb %0" : "+m" ((xl)->spinners) : : "memory");
-#else
-typedef u16 xen_spinners_t;
-# define inc_spinners(xl) \
-        asm(LOCK_PREFIX " incw %0" : "+m" ((xl)->spinners) : : "memory");
-# define dec_spinners(xl) \
-        asm(LOCK_PREFIX " decw %0" : "+m" ((xl)->spinners) : : "memory");
-#endif
-
 struct xen_lock_waiting {
         struct arch_spinlock *lock;
         __ticket_t want;
@@ -123,6 +105,7 @@ static DEFINE_PER_CPU(char *, irq_name);
 static DEFINE_PER_CPU(struct xen_lock_waiting, lock_waiting);
 static cpumask_t waiting_cpus;
 
+static bool xen_pvspin = true;
 static void xen_lock_spinning(struct arch_spinlock *lock, __ticket_t want)
 {
         int irq = __this_cpu_read(lock_kicker_irq);
@@ -241,16 +224,12 @@ void xen_init_lock_cpu(int cpu)
         int irq;
         char *name;
 
+        if (!xen_pvspin)
+                return;
+
         WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
              cpu, per_cpu(lock_kicker_irq, cpu));
 
-        /*
-         * See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23
-         * (xen: disable PV spinlocks on HVM)
-         */
-        if (xen_hvm_domain())
-                return;
-
         name = kasprintf(GFP_KERNEL, "spinlock%d", cpu);
         irq = bind_ipi_to_irqhandler(XEN_SPIN_UNLOCK_VECTOR,
                                      cpu,
@@ -270,11 +249,7 @@ void xen_init_lock_cpu(int cpu)
 
 void xen_uninit_lock_cpu(int cpu)
 {
-        /*
-         * See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23
-         * (xen: disable PV spinlocks on HVM)
-         */
-        if (xen_hvm_domain())
+        if (!xen_pvspin)
                 return;
 
         unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL);
@@ -283,16 +258,9 @@ void xen_uninit_lock_cpu(int cpu)
         per_cpu(irq_name, cpu) = NULL;
 }
 
-static bool xen_pvspin __initdata = true;
 
 void __init xen_init_spinlocks(void)
 {
-        /*
-         * See git commit f10cd522c5fbfec9ae3cc01967868c9c2401ed23
-         * (xen: disable PV spinlocks on HVM)
-         */
-        if (xen_hvm_domain())
-                return;
 
         if (!xen_pvspin) {
                 printk(KERN_DEBUG "xen: PV spinlocks disabled\n");
@@ -323,6 +291,9 @@ static int __init xen_spinlock_debugfs(void)
         if (d_xen == NULL)
                 return -ENOMEM;
 
+        if (!xen_pvspin)
+                return 0;
+
         d_spin_debug = debugfs_create_dir("spinlocks", d_xen);
 
         debugfs_create_u8("zero_stats", 0644, d_spin_debug, &zero_stats);