diff options
| author | Manfred Spraul <manfred@colorfullife.com> | 2005-01-04 05:31:02 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-01-04 05:31:02 -0800 |
| commit | 17b3fed12daae4af3b970beac31a182dc6cee044 (patch) | |
| tree | fe7f40fde16aa74c85a512bf9e789b49e44a5735 /include | |
| parent | 2f803905de112869f6f45ba52bd266254053a912 (diff) | |
[PATCH] rcu: simplify quiescent state detection
Based on an initial patch from Oleg Nesterov <oleg@tv-sign.ru>
rcu_data.last_qsctr is not needed. Actually, not even a counter is needed,
just a flag that indicates that there was a quiescent state.
Signed-Off-By: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/rcupdate.h | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 3f6c5e4cb92c..4d747433916b 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -87,9 +87,7 @@ static inline int rcu_batch_after(long a, long b) struct rcu_data { /* 1) quiescent state handling : */ long quiescbatch; /* Batch # for grace period */ - long qsctr; /* User-mode/idle loop etc. */ - long last_qsctr; /* value of qsctr at beginning */ - /* of rcu grace period */ + int passed_quiesc; /* User-mode/idle loop etc. */ int qs_pending; /* core waits for quiesc state */ /* 2) batch handling */ @@ -109,17 +107,20 @@ extern struct rcu_ctrlblk rcu_ctrlblk; extern struct rcu_ctrlblk rcu_bh_ctrlblk; /* - * Increment the quiscent state counter. + * Increment the quiescent state counter. + * The counter is a bit degenerated: We do not need to know + * how many quiescent states passed, just if there was at least + * one since the start of the grace period. Thus just a flag. */ static inline void rcu_qsctr_inc(int cpu) { struct rcu_data *rdp = &per_cpu(rcu_data, cpu); - rdp->qsctr++; + rdp->passed_quiesc = 1; } static inline void rcu_bh_qsctr_inc(int cpu) { struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu); - rdp->qsctr++; + rdp->passed_quiesc = 1; } static inline int __rcu_pending(struct rcu_ctrlblk *rcp, |