diff options
-rw-r--r-- | arch/loongarch/include/asm/Kbuild | 1 | ||||
-rw-r--r-- | arch/loongarch/include/asm/paravirt.h | 7 | ||||
-rw-r--r-- | arch/loongarch/include/asm/qspinlock.h | 41 | ||||
-rw-r--r-- | arch/loongarch/kernel/paravirt.c | 11 | ||||
-rw-r--r-- | arch/loongarch/kernel/setup.c | 2 | ||||
-rw-r--r-- | arch/loongarch/kernel/smp.c | 4 |
6 files changed, 64 insertions, 2 deletions
diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild index 2bb3676429c0..4635b755b2b4 100644 --- a/arch/loongarch/include/asm/Kbuild +++ b/arch/loongarch/include/asm/Kbuild @@ -6,7 +6,6 @@ generic-y += mcs_spinlock.h generic-y += parport.h generic-y += early_ioremap.h generic-y += qrwlock.h -generic-y += qspinlock.h generic-y += user.h generic-y += ioctl.h generic-y += statfs.h diff --git a/arch/loongarch/include/asm/paravirt.h b/arch/loongarch/include/asm/paravirt.h index dddec49671ae..3f4323603e6a 100644 --- a/arch/loongarch/include/asm/paravirt.h +++ b/arch/loongarch/include/asm/paravirt.h @@ -19,6 +19,7 @@ static inline u64 paravirt_steal_clock(int cpu) int __init pv_ipi_init(void); int __init pv_time_init(void); +int __init pv_spinlock_init(void); #else @@ -31,5 +32,11 @@ static inline int pv_time_init(void) { return 0; } + +static inline int pv_spinlock_init(void) +{ + return 0; +} + #endif // CONFIG_PARAVIRT #endif diff --git a/arch/loongarch/include/asm/qspinlock.h b/arch/loongarch/include/asm/qspinlock.h new file mode 100644 index 000000000000..e76d3aa1e1eb --- /dev/null +++ b/arch/loongarch/include/asm/qspinlock.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_LOONGARCH_QSPINLOCK_H +#define _ASM_LOONGARCH_QSPINLOCK_H + +#include <linux/jump_label.h> + +#ifdef CONFIG_PARAVIRT + +DECLARE_STATIC_KEY_FALSE(virt_spin_lock_key); + +#define virt_spin_lock virt_spin_lock + +static inline bool virt_spin_lock(struct qspinlock *lock) +{ + int val; + + if (!static_branch_unlikely(&virt_spin_lock_key)) + return false; + + /* + * On hypervisors without PARAVIRT_SPINLOCKS support we fall + * back to a Test-and-Set spinlock, because fair locks have + * horrible lock 'holder' preemption issues. + */ + +__retry: + val = atomic_read(&lock->val); + + if (val || !atomic_try_cmpxchg(&lock->val, &val, _Q_LOCKED_VAL)) { + cpu_relax(); + goto __retry; + } + + return true; +} + +#endif /* CONFIG_PARAVIRT */ + +#include <asm-generic/qspinlock.h> + +#endif // _ASM_LOONGARCH_QSPINLOCK_H diff --git a/arch/loongarch/kernel/paravirt.c b/arch/loongarch/kernel/paravirt.c index 9c9b75b76f62..32537e9b1708 100644 --- a/arch/loongarch/kernel/paravirt.c +++ b/arch/loongarch/kernel/paravirt.c @@ -13,6 +13,7 @@ static int has_steal_clock; struct static_key paravirt_steal_enabled; struct static_key paravirt_steal_rq_enabled; static DEFINE_PER_CPU(struct kvm_steal_time, steal_time) __aligned(64); +DEFINE_STATIC_KEY_FALSE(virt_spin_lock_key); static u64 native_steal_clock(int cpu) { @@ -300,3 +301,13 @@ int __init pv_time_init(void) return 0; } + +int __init pv_spinlock_init(void) +{ + if (!cpu_has_hypervisor) + return 0; + + static_branch_enable(&virt_spin_lock_key); + + return 0; +} diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c index 0f0740f0be27..00e307203ddb 100644 --- a/arch/loongarch/kernel/setup.c +++ b/arch/loongarch/kernel/setup.c @@ -603,6 +603,8 @@ void __init setup_arch(char **cmdline_p) arch_mem_init(cmdline_p); resource_init(); + jump_label_init(); /* Initialise the static keys for paravirtualization */ + #ifdef CONFIG_SMP plat_smp_setup(); prefill_possible_map(); diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c index ca405ab86aae..482b3c7e3042 100644 --- a/arch/loongarch/kernel/smp.c +++ b/arch/loongarch/kernel/smp.c @@ -476,7 +476,7 @@ core_initcall(ipi_pm_init); #endif /* Preload SMP state for boot cpu */ -void smp_prepare_boot_cpu(void) +void __init smp_prepare_boot_cpu(void) { unsigned int cpu, node, rr_node; @@ -509,6 +509,8 @@ void smp_prepare_boot_cpu(void) rr_node = next_node_in(rr_node, node_online_map); } } + + pv_spinlock_init(); } /* called from main before smp_init() */ |