diff options
Diffstat (limited to 'kernel/locking/mcs_spinlock.h')
| -rw-r--r-- | kernel/locking/mcs_spinlock.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/kernel/locking/mcs_spinlock.h b/kernel/locking/mcs_spinlock.h index f2a5c6360083..a2dbac4aca6b 100644 --- a/kernel/locking/mcs_spinlock.h +++ b/kernel/locking/mcs_spinlock.h @@ -111,4 +111,19 @@ void mcs_spin_unlock(struct mcs_spinlock **lock, struct mcs_spinlock *node) arch_mcs_spin_unlock_contended(&next->locked); } +/* + * Cancellable version of the MCS lock above. + * + * Intended for adaptive spinning of sleeping locks: + * mutex_lock()/rwsem_down_{read,write}() etc. + */ + +struct optimistic_spin_queue { + struct optimistic_spin_queue *next, *prev; + int locked; /* 1 if lock acquired */ +}; + +extern bool osq_lock(struct optimistic_spin_queue **lock); +extern void osq_unlock(struct optimistic_spin_queue **lock); + #endif /* __LINUX_MCS_SPINLOCK_H */ |