From e86e2311ae3c844a1efe4f6d569dfb548f7f58c7 Mon Sep 17 00:00:00 2001 From: Dipankar Sarma Date: Sun, 22 Aug 2004 22:57:53 -0700 Subject: [PATCH] rcu: clean up code Avoids per_cpu calculations and also prepares for call_rcu_bh(). At OLS, Rusty had suggested getting rid of many per_cpu() calculations in RCU code and making the code simpler. I had already done that for the rcu-softirq patch earlier, so I am splitting that into two patch. This first patch cleans up the macros and uses pointers to the rcu per-cpu data directly to manipulate the callback queues. This is useful for the call-rcu-bh patch (to follow) which introduces a new RCU mechanism - call_rcu_bh(). Both generic and softirq rcu can then use the same code, they work different global and percpu data. Signed-off-by: Dipankar Sarma Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/rcupdate.h | 40 ++++++++++++++++++++++------------------ 1 file changed, 22 insertions(+), 18 deletions(-) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index b689ab6108bd..45ca384109e1 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -101,47 +101,51 @@ struct rcu_data { struct rcu_head **curtail; struct rcu_head *donelist; struct rcu_head **donetail; + int cpu; }; DECLARE_PER_CPU(struct rcu_data, rcu_data); extern struct rcu_ctrlblk rcu_ctrlblk; -#define RCU_quiescbatch(cpu) (per_cpu(rcu_data, (cpu)).quiescbatch) -#define RCU_qsctr(cpu) (per_cpu(rcu_data, (cpu)).qsctr) -#define RCU_last_qsctr(cpu) (per_cpu(rcu_data, (cpu)).last_qsctr) -#define RCU_qs_pending(cpu) (per_cpu(rcu_data, (cpu)).qs_pending) -#define RCU_batch(cpu) (per_cpu(rcu_data, (cpu)).batch) -#define RCU_nxtlist(cpu) (per_cpu(rcu_data, (cpu)).nxtlist) -#define RCU_curlist(cpu) (per_cpu(rcu_data, (cpu)).curlist) -#define RCU_nxttail(cpu) (per_cpu(rcu_data, (cpu)).nxttail) -#define RCU_curtail(cpu) (per_cpu(rcu_data, (cpu)).curtail) -#define RCU_donelist(cpu) (per_cpu(rcu_data, (cpu)).donelist) -#define RCU_donetail(cpu) (per_cpu(rcu_data, (cpu)).donetail) - -static inline int rcu_pending(int cpu) +/* + * Increment the quiscent state counter. + */ +static inline void rcu_qsctr_inc(int cpu) +{ + struct rcu_data *rdp = &per_cpu(rcu_data, cpu); + rdp->qsctr++; +} + +static inline int __rcu_pending(struct rcu_ctrlblk *rcp, + struct rcu_data *rdp) { /* This cpu has pending rcu entries and the grace period * for them has completed. */ - if (RCU_curlist(cpu) && - !rcu_batch_before(rcu_ctrlblk.completed,RCU_batch(cpu))) + if (rdp->curlist && !rcu_batch_before(rcp->completed, rdp->batch)) return 1; /* This cpu has no pending entries, but there are new entries */ - if (!RCU_curlist(cpu) && RCU_nxtlist(cpu)) + if (!rdp->curlist && rdp->nxtlist) return 1; - if (RCU_donelist(cpu)) + /* This cpu has finished callbacks to invoke */ + if (rdp->donelist) return 1; /* The rcu core waits for a quiescent state from the cpu */ - if (RCU_quiescbatch(cpu) != rcu_ctrlblk.cur || RCU_qs_pending(cpu)) + if (rdp->quiescbatch != rcp->cur || rdp->qs_pending) return 1; /* nothing to do */ return 0; } +static inline int rcu_pending(int cpu) +{ + return __rcu_pending(&rcu_ctrlblk, &per_cpu(rcu_data, cpu)); +} + #define rcu_read_lock() preempt_disable() #define rcu_read_unlock() preempt_enable() -- cgit v1.2.3