diff options
| -rw-r--r-- | fs/dcache.c | 51 | ||||
| -rw-r--r-- | fs/namei.c | 2 | ||||
| -rw-r--r-- | kernel/rcutree.c | 26 | ||||
| -rw-r--r-- | kernel/rcutree_plugin.h | 15 | ||||
| -rw-r--r-- | kernel/sched.c | 3 |
5 files changed, 75 insertions, 22 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 37f72ee5bf7c..6e4ea6d87774 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2213,14 +2213,15 @@ static void dentry_unlock_parents_for_move(struct dentry *dentry, * The hash value has to match the hash queue that the dentry is on.. */ /* - * d_move - move a dentry + * __d_move - move a dentry * @dentry: entry to move * @target: new dentry * * Update the dcache to reflect the move of a file name. Negative - * dcache entries should not be moved in this way. + * dcache entries should not be moved in this way. Caller hold + * rename_lock. */ -void d_move(struct dentry * dentry, struct dentry * target) +static void __d_move(struct dentry * dentry, struct dentry * target) { if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry\n"); @@ -2228,8 +2229,6 @@ void d_move(struct dentry * dentry, struct dentry * target) BUG_ON(d_ancestor(dentry, target)); BUG_ON(d_ancestor(target, dentry)); - write_seqlock(&rename_lock); - dentry_lock_for_move(dentry, target); write_seqcount_begin(&dentry->d_seq); @@ -2275,6 +2274,20 @@ void d_move(struct dentry * dentry, struct dentry * target) spin_unlock(&target->d_lock); fsnotify_d_move(dentry); spin_unlock(&dentry->d_lock); +} + +/* + * d_move - move a dentry + * @dentry: entry to move + * @target: new dentry + * + * Update the dcache to reflect the move of a file name. Negative + * dcache entries should not be moved in this way. + */ +void d_move(struct dentry *dentry, struct dentry *target) +{ + write_seqlock(&rename_lock); + __d_move(dentry, target); write_sequnlock(&rename_lock); } EXPORT_SYMBOL(d_move); @@ -2302,7 +2315,7 @@ struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2) * This helper attempts to cope with remotely renamed directories * * It assumes that the caller is already holding - * dentry->d_parent->d_inode->i_mutex and the inode->i_lock + * dentry->d_parent->d_inode->i_mutex, inode->i_lock and rename_lock * * Note: If ever the locking in lock_rename() changes, then please * remember to update this too... @@ -2317,11 +2330,6 @@ static struct dentry *__d_unalias(struct inode *inode, if (alias->d_parent == dentry->d_parent) goto out_unalias; - /* Check for loops */ - ret = ERR_PTR(-ELOOP); - if (d_ancestor(alias, dentry)) - goto out_err; - /* See lock_rename() */ ret = ERR_PTR(-EBUSY); if (!mutex_trylock(&dentry->d_sb->s_vfs_rename_mutex)) @@ -2331,7 +2339,7 @@ static struct dentry *__d_unalias(struct inode *inode, goto out_err; m2 = &alias->d_parent->d_inode->i_mutex; out_unalias: - d_move(alias, dentry); + __d_move(alias, dentry); ret = alias; out_err: spin_unlock(&inode->i_lock); @@ -2416,15 +2424,24 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) alias = __d_find_alias(inode, 0); if (alias) { actual = alias; - /* Is this an anonymous mountpoint that we could splice - * into our tree? */ - if (IS_ROOT(alias)) { + write_seqlock(&rename_lock); + + if (d_ancestor(alias, dentry)) { + /* Check for loops */ + actual = ERR_PTR(-ELOOP); + } else if (IS_ROOT(alias)) { + /* Is this an anonymous mountpoint that we + * could splice into our tree? */ __d_materialise_dentry(dentry, alias); + write_sequnlock(&rename_lock); __d_drop(alias); goto found; + } else { + /* Nope, but we must(!) avoid directory + * aliasing */ + actual = __d_unalias(inode, dentry, alias); } - /* Nope, but we must(!) avoid directory aliasing */ - actual = __d_unalias(inode, dentry, alias); + write_sequnlock(&rename_lock); if (IS_ERR(actual)) dput(alias); goto out_nolock; diff --git a/fs/namei.c b/fs/namei.c index 0223c41fb114..5c867dd1c0b3 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -433,6 +433,8 @@ static int unlazy_walk(struct nameidata *nd, struct dentry *dentry) goto err_parent; BUG_ON(nd->inode != parent->d_inode); } else { + if (dentry->d_parent != parent) + goto err_parent; spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); if (!__d_rcu_to_refcount(dentry, nd->seq)) goto err_child; diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 7e59ffb3d0ba..ba06207b1dd3 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -84,9 +84,32 @@ DEFINE_PER_CPU(struct rcu_data, rcu_bh_data); static struct rcu_state *rcu_state; +/* + * The rcu_scheduler_active variable transitions from zero to one just + * before the first task is spawned. So when this variable is zero, RCU + * can assume that there is but one task, allowing RCU to (for example) + * optimized synchronize_sched() to a simple barrier(). When this variable + * is one, RCU must actually do all the hard work required to detect real + * grace periods. This variable is also used to suppress boot-time false + * positives from lockdep-RCU error checking. + */ int rcu_scheduler_active __read_mostly; EXPORT_SYMBOL_GPL(rcu_scheduler_active); +/* + * The rcu_scheduler_fully_active variable transitions from zero to one + * during the early_initcall() processing, which is after the scheduler + * is capable of creating new tasks. So RCU processing (for example, + * creating tasks for RCU priority boosting) must be delayed until after + * rcu_scheduler_fully_active transitions from zero to one. We also + * currently delay invocation of any RCU callbacks until after this point. + * + * It might later prove better for people registering RCU callbacks during + * early boot to take responsibility for these callbacks, but one step at + * a time. + */ +static int rcu_scheduler_fully_active __read_mostly; + #ifdef CONFIG_RCU_BOOST /* @@ -98,7 +121,6 @@ DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status); DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu); DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); DEFINE_PER_CPU(char, rcu_cpu_has_work); -static char rcu_kthreads_spawnable; #endif /* #ifdef CONFIG_RCU_BOOST */ @@ -1467,6 +1489,8 @@ static void rcu_process_callbacks(struct softirq_action *unused) */ static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp) { + if (unlikely(!ACCESS_ONCE(rcu_scheduler_fully_active))) + return; if (likely(!rsp->boost)) { rcu_do_batch(rsp, rdp); return; diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 14dc7dd00902..75113cb7c4fb 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -1532,7 +1532,7 @@ static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu) struct sched_param sp; struct task_struct *t; - if (!rcu_kthreads_spawnable || + if (!rcu_scheduler_fully_active || per_cpu(rcu_cpu_kthread_task, cpu) != NULL) return 0; t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu); @@ -1639,7 +1639,7 @@ static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp, struct sched_param sp; struct task_struct *t; - if (!rcu_kthreads_spawnable || + if (!rcu_scheduler_fully_active || rnp->qsmaskinit == 0) return 0; if (rnp->node_kthread_task == NULL) { @@ -1665,7 +1665,7 @@ static int __init rcu_spawn_kthreads(void) int cpu; struct rcu_node *rnp; - rcu_kthreads_spawnable = 1; + rcu_scheduler_fully_active = 1; for_each_possible_cpu(cpu) { per_cpu(rcu_cpu_has_work, cpu) = 0; if (cpu_online(cpu)) @@ -1687,7 +1687,7 @@ static void __cpuinit rcu_prepare_kthreads(int cpu) struct rcu_node *rnp = rdp->mynode; /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */ - if (rcu_kthreads_spawnable) { + if (rcu_scheduler_fully_active) { (void)rcu_spawn_one_cpu_kthread(cpu); if (rnp->node_kthread_task == NULL) (void)rcu_spawn_one_node_kthread(rcu_state, rnp); @@ -1726,6 +1726,13 @@ static void rcu_cpu_kthread_setrt(int cpu, int to_rt) { } +static int __init rcu_scheduler_really_started(void) +{ + rcu_scheduler_fully_active = 1; + return 0; +} +early_initcall(rcu_scheduler_really_started); + static void __cpuinit rcu_prepare_kthreads(int cpu) { } diff --git a/kernel/sched.c b/kernel/sched.c index 9769c756ad66..3dc716f6d8ad 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -7757,6 +7757,9 @@ static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq) #endif #endif cfs_rq->min_vruntime = (u64)(-(1LL << 20)); +#ifndef CONFIG_64BIT + cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime; +#endif } static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) |