#include <linux/module.h>
#include <linux/backing-dev.h>
#include <linux/wait.h>
+#include <linux/rwsem.h>
#include <linux/hash.h>
#include <linux/swap.h>
#include <linux/security.h>
DEFINE_SPINLOCK(inode_lock);
/*
- * iprune_mutex provides exclusion between the kswapd or try_to_free_pages
+ * iprune_sem provides exclusion between the kswapd or try_to_free_pages
* icache shrinking path, and the umount path. Without this exclusion,
* by the time prune_icache calls iput for the inode whose pages it has
* been invalidating, or by the time it calls clear_inode & destroy_inode
* from its final dispose_list, the struct super_block they refer to
* (for inode->i_sb->s_op) may already have been freed and reused.
+ *
+ * We make this an rwsem because the fastpath is icache shrinking. In
+ * some cases a filesystem may be doing a significant amount of work in
+ * its inode reclaim code, so this should improve parallelism.
*/
-static DEFINE_MUTEX(iprune_mutex);
+static DECLARE_RWSEM(iprune_sem);
/*
* Statistics gathering..
/*
* We can reschedule here without worrying about the list's
* consistency because the per-sb list of inodes must not
- * change during umount anymore, and because iprune_mutex keeps
+ * change during umount anymore, and because iprune_sem keeps
* shrink_icache_memory() away.
*/
cond_resched_lock(&inode_lock);
int busy;
LIST_HEAD(throw_away);
- mutex_lock(&iprune_mutex);
+ down_write(&iprune_sem);
spin_lock(&inode_lock);
inotify_unmount_inodes(&sb->s_inodes);
fsnotify_unmount_inodes(&sb->s_inodes);
spin_unlock(&inode_lock);
dispose_list(&throw_away);
- mutex_unlock(&iprune_mutex);
+ up_write(&iprune_sem);
return busy;
}
int nr_scanned;
unsigned long reap = 0;
- mutex_lock(&iprune_mutex);
+ down_read(&iprune_sem);
spin_lock(&inode_lock);
for (nr_scanned = 0; nr_scanned < nr_to_scan; nr_scanned++) {
struct inode *inode;
spin_unlock(&inode_lock);
dispose_list(&freeable);
- mutex_unlock(&iprune_mutex);
+ up_read(&iprune_sem);
}
/*
}
EXPORT_SYMBOL(generic_delete_inode);
-static void generic_forget_inode(struct inode *inode)
+/**
+ * generic_detach_inode - remove inode from inode lists
+ * @inode: inode to remove
+ *
+ * Remove inode from inode lists, write it if it's dirty. This is just an
+ * internal VFS helper exported for hugetlbfs. Do not use!
+ *
+ * Returns 1 if inode should be completely destroyed.
+ */
+int generic_detach_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
inodes_stat.nr_unused++;
if (sb->s_flags & MS_ACTIVE) {
spin_unlock(&inode_lock);
- return;
+ return 0;
}
WARN_ON(inode->i_state & I_NEW);
inode->i_state |= I_WILL_FREE;
inode->i_state |= I_FREEING;
inodes_stat.nr_inodes--;
spin_unlock(&inode_lock);
+ return 1;
+}
+EXPORT_SYMBOL_GPL(generic_detach_inode);
+
+static void generic_forget_inode(struct inode *inode)
+{
+ if (!generic_detach_inode(inode))
+ return;
if (inode->i_data.nrpages)
truncate_inode_pages(&inode->i_data, 0);
clear_inode(inode);
else if (S_ISSOCK(mode))
inode->i_fop = &bad_sock_fops;
else
- printk(KERN_DEBUG "init_special_inode: bogus i_mode (%o)\n",
- mode);
+ printk(KERN_DEBUG "init_special_inode: bogus i_mode (%o) for"
+ " inode %s:%lu\n", mode, inode->i_sb->s_id,
+ inode->i_ino);
}
EXPORT_SYMBOL(init_special_inode);