diff options
Diffstat (limited to 'fs/dcache.c')
| -rw-r--r-- | fs/dcache.c | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 6e4ea6d8777..d3902139b53 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -344,6 +344,24 @@ void d_drop(struct dentry *dentry) EXPORT_SYMBOL(d_drop); /* + * d_clear_need_lookup - drop a dentry from cache and clear the need lookup flag + * @dentry: dentry to drop + * + * This is called when we do a lookup on a placeholder dentry that needed to be + * looked up. The dentry should have been hashed in order for it to be found by + * the lookup code, but now needs to be unhashed while we do the actual lookup + * and clear the DCACHE_NEED_LOOKUP flag. + */ +void d_clear_need_lookup(struct dentry *dentry) +{ + spin_lock(&dentry->d_lock); + __d_drop(dentry); + dentry->d_flags &= ~DCACHE_NEED_LOOKUP; + spin_unlock(&dentry->d_lock); +} +EXPORT_SYMBOL(d_clear_need_lookup); + +/* * Finish off a dentry we've decided to kill. * dentry->d_lock must be held, returns with it unlocked. * If ref is non-zero, then decrement the refcount too. @@ -432,8 +450,13 @@ repeat: if (d_unhashed(dentry)) goto kill_it; - /* Otherwise leave it cached and ensure it's on the LRU */ - dentry->d_flags |= DCACHE_REFERENCED; + /* + * If this dentry needs lookup, don't set the referenced flag so that it + * is more likely to be cleaned up by the dcache shrinker in case of + * memory pressure. + */ + if (!d_need_lookup(dentry)) + dentry->d_flags |= DCACHE_REFERENCED; dentry_lru_add(dentry); dentry->d_count--; @@ -1708,6 +1731,13 @@ struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, } /* + * We are going to instantiate this dentry, unhash it and clear the + * lookup flag so we can do that. + */ + if (unlikely(d_need_lookup(found))) + d_clear_need_lookup(found); + + /* * Negative dentry: instantiate it unless the inode is a directory and * already has a dentry. */ |