diff options
Diffstat (limited to 'kernel/rcu/rcu.h')
| -rw-r--r-- | kernel/rcu/rcu.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index 7b4a88deff9a..be5979da07f5 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -19,6 +19,9 @@ #define RCU_SEQ_CTR_SHIFT 2 #define RCU_SEQ_STATE_MASK ((1 << RCU_SEQ_CTR_SHIFT) - 1) +/* Low-order bit definition for polled grace-period APIs. */ +#define RCU_GET_STATE_COMPLETED 0x1 + extern int sysctl_sched_rt_runtime; /* @@ -116,6 +119,18 @@ static inline bool rcu_seq_done(unsigned long *sp, unsigned long s) } /* + * Given a snapshot from rcu_seq_snap(), determine whether or not a + * full update-side operation has occurred, but do not allow the + * (ULONG_MAX / 2) safety-factor/guard-band. + */ +static inline bool rcu_seq_done_exact(unsigned long *sp, unsigned long s) +{ + unsigned long cur_s = READ_ONCE(*sp); + + return ULONG_CMP_GE(cur_s, s) || ULONG_CMP_LT(cur_s, s - (2 * RCU_SEQ_STATE_MASK + 1)); +} + +/* * Has a grace period completed since the time the old gp_seq was collected? */ static inline bool rcu_seq_completed_gp(unsigned long old, unsigned long new) |