From: Zengruan Ye yezengruan@huawei.com
virt inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8WMFU CVE: NA
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As kernel has used this interface, so lets support it.
Signed-off-by: Zengruan Ye yezengruan@huawei.com Reviewed-by: Zhanghailiang zhang.zhanghailiang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com
Signed-off-by: lishusen lishusen2@huawei.com --- arch/arm64/Kconfig | 13 ++++++ arch/arm64/include/asm/Kbuild | 1 - arch/arm64/include/asm/paravirt.h | 25 +++++++++++ arch/arm64/include/asm/qspinlock.h | 48 +++++++++++++++++++++ arch/arm64/include/asm/qspinlock_paravirt.h | 12 ++++++ arch/arm64/include/asm/spinlock.h | 3 ++ arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/paravirt-spinlocks.c | 5 +++ 8 files changed, 107 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/include/asm/qspinlock.h create mode 100644 arch/arm64/include/asm/qspinlock_paravirt.h
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 9568049f36e3..c21b663b34d2 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1548,6 +1548,19 @@ config PARAVIRT under a hypervisor, potentially improving performance significantly over full virtualization.
+config PARAVIRT_SPINLOCKS + bool "Paravirtualization layer for spinlocks" + depends on PARAVIRT && SMP + help + Paravirtualized spinlocks allow a pvops backend to replace the + spinlock implementation with something virtualization-friendly + (for example, block the virtual CPU rather than spinning). + + It has a minimal impact on native kernels and gives a nice performance + benefit on paravirtualized KVM kernels. + + If you are unsure how to answer this question, answer Y. + config PARAVIRT_TIME_ACCOUNTING bool "Paravirtual steal time accounting" select PARAVIRT diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild index 5c8ee5a541d2..d16ee8095366 100644 --- a/arch/arm64/include/asm/Kbuild +++ b/arch/arm64/include/asm/Kbuild @@ -2,7 +2,6 @@ generic-y += early_ioremap.h generic-y += mcs_spinlock.h generic-y += qrwlock.h -generic-y += qspinlock.h generic-y += parport.h generic-y += user.h
diff --git a/arch/arm64/include/asm/paravirt.h b/arch/arm64/include/asm/paravirt.h index 4e35851bcecf..1c9011d31562 100644 --- a/arch/arm64/include/asm/paravirt.h +++ b/arch/arm64/include/asm/paravirt.h @@ -30,6 +30,31 @@ static inline bool pv_vcpu_is_preempted(int cpu) return static_call(pv_vcpu_preempted)(cpu); }
+#if defined(CONFIG_SMP) && defined(CONFIG_PARAVIRT_SPINLOCKS) +bool pv_is_native_spin_unlock(void); +DECLARE_STATIC_CALL(pv_qspinlock_queued_spin_lock_slowpath, native_queued_spin_lock_slowpath); +static inline void pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) +{ + return static_call(pv_qspinlock_queued_spin_lock_slowpath)(lock, val); +} + +DECLARE_STATIC_CALL(pv_qspinlock_queued_spin_unlock, native_queued_spin_unlock); +static inline void pv_queued_spin_unlock(struct qspinlock *lock) +{ + return static_call(pv_qspinlock_queued_spin_unlock)(lock); +} + +static inline void pv_wait(u8 *ptr, u8 val) +{ + return; +} + +static inline void pv_kick(int cpu) +{ + return; +} +#endif /* SMP && PARAVIRT_SPINLOCKS */ + #else
#define pv_time_init() do {} while (0) diff --git a/arch/arm64/include/asm/qspinlock.h b/arch/arm64/include/asm/qspinlock.h new file mode 100644 index 000000000000..ce3816b60f25 --- /dev/null +++ b/arch/arm64/include/asm/qspinlock.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright(c) 2020 Huawei Technologies Co., Ltd + * Author: Zengruan Ye yezengruan@huawei.com + */ + +#ifndef _ASM_ARM64_QSPINLOCK_H +#define _ASM_ARM64_QSPINLOCK_H + +#include <linux/jump_label.h> +#include <asm/cpufeature.h> +#include <asm-generic/qspinlock_types.h> +#include <asm/paravirt.h> + +#define _Q_PENDING_LOOPS (1 << 9) + +#ifdef CONFIG_PARAVIRT_SPINLOCKS +extern void native_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); +extern void __pv_init_lock_hash(void); +extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); + +#define queued_spin_unlock queued_spin_unlock +/** + * queued_spin_unlock - release a queued spinlock + * @lock : Pointer to queued spinlock structure + * + * A smp_store_release() on the least-significant byte. + */ +static inline void native_queued_spin_unlock(struct qspinlock *lock) +{ + smp_store_release(&lock->locked, 0); +} + +static inline void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) +{ + pv_queued_spin_lock_slowpath(lock, val); +} + +static inline void queued_spin_unlock(struct qspinlock *lock) +{ + pv_queued_spin_unlock(lock); +} + +#endif + +#include <asm-generic/qspinlock.h> + +#endif /* _ASM_ARM64_QSPINLOCK_H */ diff --git a/arch/arm64/include/asm/qspinlock_paravirt.h b/arch/arm64/include/asm/qspinlock_paravirt.h new file mode 100644 index 000000000000..eba4be28fbb9 --- /dev/null +++ b/arch/arm64/include/asm/qspinlock_paravirt.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright(c) 2019 Huawei Technologies Co., Ltd + * Author: Zengruan Ye yezengruan@huawei.com + */ + +#ifndef __ASM_QSPINLOCK_PARAVIRT_H +#define __ASM_QSPINLOCK_PARAVIRT_H + +extern void __pv_queued_spin_unlock(struct qspinlock *lock); + +#endif diff --git a/arch/arm64/include/asm/spinlock.h b/arch/arm64/include/asm/spinlock.h index 3dcb1c903ba0..4040a27ecf86 100644 --- a/arch/arm64/include/asm/spinlock.h +++ b/arch/arm64/include/asm/spinlock.h @@ -9,6 +9,9 @@ #include <asm/qrwlock.h> #include <asm/paravirt.h>
+/* How long a lock should spin before we consider blocking */ +#define SPIN_THRESHOLD (1 << 15) + /* See include/linux/spinlock.h */ #define smp_mb__after_spinlock() smp_mb()
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 235963ed87b1..4db14d6677bd 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -61,6 +61,7 @@ obj-$(CONFIG_ACPI) += acpi.o obj-$(CONFIG_ACPI_NUMA) += acpi_numa.o obj-$(CONFIG_ARM64_ACPI_PARKING_PROTOCOL) += acpi_parking_protocol.o obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt-spinlocks.o +obj-$(CONFIG_PARAVIRT_SPINLOCKS) += paravirt.o paravirt-spinlocks.o obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o pi/ obj-$(CONFIG_HIBERNATION) += hibernate.o hibernate-asm.o obj-$(CONFIG_ELF_CORE) += elfcore.o diff --git a/arch/arm64/kernel/paravirt-spinlocks.c b/arch/arm64/kernel/paravirt-spinlocks.c index 3566897070d9..2e4abc83e318 100644 --- a/arch/arm64/kernel/paravirt-spinlocks.c +++ b/arch/arm64/kernel/paravirt-spinlocks.c @@ -14,3 +14,8 @@ __visible bool __native_vcpu_is_preempted(int cpu) }
DEFINE_STATIC_CALL(pv_vcpu_preempted, __native_vcpu_is_preempted); + +bool pv_is_native_spin_unlock(void) +{ + return false; +}