diff options
Diffstat (limited to 'kernel/rcupdate.c')
| -rw-r--r-- | kernel/rcupdate.c | 49 |
1 files changed, 33 insertions, 16 deletions
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index 48d3bce465b..ccc45d49ce7 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -35,6 +35,7 @@ #include <linux/init.h> #include <linux/spinlock.h> #include <linux/smp.h> +#include <linux/rcupdate.h> #include <linux/interrupt.h> #include <linux/sched.h> #include <asm/atomic.h> @@ -45,7 +46,6 @@ #include <linux/percpu.h> #include <linux/notifier.h> #include <linux/rcupdate.h> -#include <linux/rcuref.h> #include <linux/cpu.h> /* Definition for rcupdate control block. */ @@ -61,9 +61,9 @@ struct rcu_state { /* for current batch to proceed. */ }; -static struct rcu_state rcu_state ____cacheline_maxaligned_in_smp = +static struct rcu_state rcu_state ____cacheline_internodealigned_in_smp = {.lock = SPIN_LOCK_UNLOCKED, .cpumask = CPU_MASK_NONE }; -static struct rcu_state rcu_bh_state ____cacheline_maxaligned_in_smp = +static struct rcu_state rcu_bh_state ____cacheline_internodealigned_in_smp = {.lock = SPIN_LOCK_UNLOCKED, .cpumask = CPU_MASK_NONE }; DEFINE_PER_CPU(struct rcu_data, rcu_data) = { 0L }; @@ -73,19 +73,6 @@ DEFINE_PER_CPU(struct rcu_data, rcu_bh_data) = { 0L }; static DEFINE_PER_CPU(struct tasklet_struct, rcu_tasklet) = {NULL}; static int maxbatch = 10000; -#ifndef __HAVE_ARCH_CMPXCHG -/* - * We use an array of spinlocks for the rcurefs -- similar to ones in sparc - * 32 bit atomic_t implementations, and a hash function similar to that - * for our refcounting needs. - * Can't help multiprocessors which donot have cmpxchg :( - */ - -spinlock_t __rcuref_hash[RCUREF_HASH_SIZE] = { - [0 ... (RCUREF_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED -}; -#endif - /** * call_rcu - Queue an RCU callback for invocation after a grace period. * @head: structure to be used for queueing the RCU updates. @@ -442,6 +429,36 @@ static void rcu_process_callbacks(unsigned long unused) &__get_cpu_var(rcu_bh_data)); } +static 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 (rdp->curlist && !rcu_batch_before(rcp->completed, rdp->batch)) + return 1; + + /* This cpu has no pending entries, but there are new entries */ + if (!rdp->curlist && rdp->nxtlist) + return 1; + + /* This cpu has finished callbacks to invoke */ + if (rdp->donelist) + return 1; + + /* The rcu core waits for a quiescent state from the cpu */ + if (rdp->quiescbatch != rcp->cur || rdp->qs_pending) + return 1; + + /* nothing to do */ + return 0; +} + +int rcu_pending(int cpu) +{ + return __rcu_pending(&rcu_ctrlblk, &per_cpu(rcu_data, cpu)) || + __rcu_pending(&rcu_bh_ctrlblk, &per_cpu(rcu_bh_data, cpu)); +} + void rcu_check_callbacks(int cpu, int user) { if (user || |