diff options
| -rw-r--r-- | arch/x86/include/asm/qspinlock.h | 14 | ||||
| -rw-r--r-- | include/asm-generic/qspinlock.h | 7 | ||||
| -rw-r--r-- | kernel/locking/qspinlock.c | 3 |
3 files changed, 24 insertions, 0 deletions
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h index e2aee8273664..f079b7020e3f 100644 --- a/arch/x86/include/asm/qspinlock.h +++ b/arch/x86/include/asm/qspinlock.h @@ -1,6 +1,7 @@ #ifndef _ASM_X86_QSPINLOCK_H #define _ASM_X86_QSPINLOCK_H +#include <asm/cpufeature.h> #include <asm-generic/qspinlock_types.h> #define queued_spin_unlock queued_spin_unlock @@ -15,6 +16,19 @@ static inline void queued_spin_unlock(struct qspinlock *lock) smp_store_release((u8 *)lock, 0); } +#define virt_queued_spin_lock virt_queued_spin_lock + +static inline bool virt_queued_spin_lock(struct qspinlock *lock) +{ + if (!static_cpu_has(X86_FEATURE_HYPERVISOR)) + return false; + + while (atomic_cmpxchg(&lock->val, 0, _Q_LOCKED_VAL) != 0) + cpu_relax(); + + return true; +} + #include <asm-generic/qspinlock.h> #endif /* _ASM_X86_QSPINLOCK_H */ diff --git a/include/asm-generic/qspinlock.h b/include/asm-generic/qspinlock.h index 569abcd47a9a..83bfb87f5bf1 100644 --- a/include/asm-generic/qspinlock.h +++ b/include/asm-generic/qspinlock.h @@ -111,6 +111,13 @@ static inline void queued_spin_unlock_wait(struct qspinlock *lock) cpu_relax(); } +#ifndef virt_queued_spin_lock +static __always_inline bool virt_queued_spin_lock(struct qspinlock *lock) +{ + return false; +} +#endif + /* * Initializier */ diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c index 033872113ebb..fd31a474145d 100644 --- a/kernel/locking/qspinlock.c +++ b/kernel/locking/qspinlock.c @@ -249,6 +249,9 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) BUILD_BUG_ON(CONFIG_NR_CPUS >= (1U << _Q_TAIL_CPU_BITS)); + if (virt_queued_spin_lock(lock)) + return; + /* * wait for in-progress pending->locked hand-overs * |