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Diffstat (limited to 'arch/x86/xen/spinlock.c')
-rw-r--r--arch/x86/xen/spinlock.c45
1 files changed, 8 insertions, 37 deletions
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);