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-rw-r--r--arch/x86/Kconfig13
-rw-r--r--arch/x86/include/asm/paravirt.h2
-rw-r--r--arch/x86/include/asm/spinlock.h4
-rw-r--r--arch/x86/kernel/Makefile3
-rw-r--r--arch/x86/kernel/paravirt.c2
-rw-r--r--arch/x86/xen/Makefile5
-rw-r--r--arch/x86/xen/xen-ops.h19
7 files changed, 38 insertions, 10 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index df9e885eee14..a6efe0a2e9ae 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -498,6 +498,19 @@ config PARAVIRT
498 over full virtualization. However, when run without a hypervisor 498 over full virtualization. However, when run without a hypervisor
499 the kernel is theoretically slower and slightly larger. 499 the kernel is theoretically slower and slightly larger.
500 500
501config PARAVIRT_SPINLOCKS
502 bool "Paravirtualization layer for spinlocks"
503 depends on PARAVIRT && SMP && EXPERIMENTAL
504 ---help---
505 Paravirtualized spinlocks allow a pvops backend to replace the
506 spinlock implementation with something virtualization-friendly
507 (for example, block the virtual CPU rather than spinning).
508
509 Unfortunately the downside is an up to 5% performance hit on
510 native kernels, with various workloads.
511
512 If you are unsure how to answer this question, answer N.
513
501config PARAVIRT_CLOCK 514config PARAVIRT_CLOCK
502 bool 515 bool
503 default n 516 default n
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 378e3691c08c..a53da004e08e 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -1443,7 +1443,7 @@ u64 _paravirt_ident_64(u64);
1443 1443
1444#define paravirt_nop ((void *)_paravirt_nop) 1444#define paravirt_nop ((void *)_paravirt_nop)
1445 1445
1446#ifdef CONFIG_SMP 1446#if defined(CONFIG_SMP) && defined(CONFIG_PARAVIRT_SPINLOCKS)
1447 1447
1448static inline int __raw_spin_is_locked(struct raw_spinlock *lock) 1448static inline int __raw_spin_is_locked(struct raw_spinlock *lock)
1449{ 1449{
diff --git a/arch/x86/include/asm/spinlock.h b/arch/x86/include/asm/spinlock.h
index e5e6caffec87..b7e5db876399 100644
--- a/arch/x86/include/asm/spinlock.h
+++ b/arch/x86/include/asm/spinlock.h
@@ -172,7 +172,7 @@ static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
172 return (((tmp >> TICKET_SHIFT) - tmp) & ((1 << TICKET_SHIFT) - 1)) > 1; 172 return (((tmp >> TICKET_SHIFT) - tmp) & ((1 << TICKET_SHIFT) - 1)) > 1;
173} 173}
174 174
175#ifndef CONFIG_PARAVIRT 175#ifndef CONFIG_PARAVIRT_SPINLOCKS
176 176
177static inline int __raw_spin_is_locked(raw_spinlock_t *lock) 177static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
178{ 178{
@@ -206,7 +206,7 @@ static __always_inline void __raw_spin_lock_flags(raw_spinlock_t *lock,
206 __raw_spin_lock(lock); 206 __raw_spin_lock(lock);
207} 207}
208 208
209#endif 209#endif /* CONFIG_PARAVIRT_SPINLOCKS */
210 210
211static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock) 211static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
212{ 212{
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 145cce75cda7..88d1bfc847d3 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -89,7 +89,8 @@ obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o
89obj-$(CONFIG_VMI) += vmi_32.o vmiclock_32.o 89obj-$(CONFIG_VMI) += vmi_32.o vmiclock_32.o
90obj-$(CONFIG_KVM_GUEST) += kvm.o 90obj-$(CONFIG_KVM_GUEST) += kvm.o
91obj-$(CONFIG_KVM_CLOCK) += kvmclock.o 91obj-$(CONFIG_KVM_CLOCK) += kvmclock.o
92obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt_patch_$(BITS).o paravirt-spinlocks.o 92obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt_patch_$(BITS).o
93obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= paravirt-spinlocks.o
93obj-$(CONFIG_PARAVIRT_CLOCK) += pvclock.o 94obj-$(CONFIG_PARAVIRT_CLOCK) += pvclock.o
94 95
95obj-$(CONFIG_PCSPKR_PLATFORM) += pcspeaker.o 96obj-$(CONFIG_PCSPKR_PLATFORM) += pcspeaker.o
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 8e45f4464880..9faf43bea336 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -134,7 +134,9 @@ static void *get_call_destination(u8 type)
134 .pv_irq_ops = pv_irq_ops, 134 .pv_irq_ops = pv_irq_ops,
135 .pv_apic_ops = pv_apic_ops, 135 .pv_apic_ops = pv_apic_ops,
136 .pv_mmu_ops = pv_mmu_ops, 136 .pv_mmu_ops = pv_mmu_ops,
137#ifdef CONFIG_PARAVIRT_SPINLOCKS
137 .pv_lock_ops = pv_lock_ops, 138 .pv_lock_ops = pv_lock_ops,
139#endif
138 }; 140 };
139 return *((void **)&tmpl + type); 141 return *((void **)&tmpl + type);
140} 142}
diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 3b767d03fd6a..172438f86a02 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -9,5 +9,6 @@ obj-y := enlighten.o setup.o multicalls.o mmu.o irq.o \
9 time.o xen-asm.o xen-asm_$(BITS).o \ 9 time.o xen-asm.o xen-asm_$(BITS).o \
10 grant-table.o suspend.o 10 grant-table.o suspend.o
11 11
12obj-$(CONFIG_SMP) += smp.o spinlock.o 12obj-$(CONFIG_SMP) += smp.o
13obj-$(CONFIG_XEN_DEBUG_FS) += debugfs.o \ No newline at end of file 13obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o
14obj-$(CONFIG_XEN_DEBUG_FS) += debugfs.o
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index 20139464943c..ca6596b05d53 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -62,15 +62,26 @@ void xen_setup_vcpu_info_placement(void);
62#ifdef CONFIG_SMP 62#ifdef CONFIG_SMP
63void xen_smp_init(void); 63void xen_smp_init(void);
64 64
65void __init xen_init_spinlocks(void);
66__cpuinit void xen_init_lock_cpu(int cpu);
67void xen_uninit_lock_cpu(int cpu);
68
69extern cpumask_var_t xen_cpu_initialized_map; 65extern cpumask_var_t xen_cpu_initialized_map;
70#else 66#else
71static inline void xen_smp_init(void) {} 67static inline void xen_smp_init(void) {}
72#endif 68#endif
73 69
70#ifdef CONFIG_PARAVIRT_SPINLOCKS
71void __init xen_init_spinlocks(void);
72__cpuinit void xen_init_lock_cpu(int cpu);
73void xen_uninit_lock_cpu(int cpu);
74#else
75static inline void xen_init_spinlocks(void)
76{
77}
78static inline void xen_init_lock_cpu(int cpu)
79{
80}
81static inline void xen_uninit_lock_cpu(int cpu)
82{
83}
84#endif
74 85
75/* Declare an asm function, along with symbols needed to make it 86/* Declare an asm function, along with symbols needed to make it
76 inlineable */ 87 inlineable */