/*
* Prune the dcache to remove unused children of the parent dentry.
*/
void shrink_dcache_parent(struct dentry * parent)
{
int found;
while ((found = select_parent(parent)) != 0)
prune_dcache(found);
}
/*
* This is called from kswapd when we think we need some
* more memory, but aren't really sure how much. So we
* carefully try to free a _bit_ of our dcache, but not
* too much.
*
* Priority:
* 0 - very urgent: shrink everything
* ...
* 6 - base-level: try to shrink a bit.
*/
void shrink_dcache_memory(int priority, unsigned int gfp_mask)
{
if (gfp_mask & __GFP_IO) {
int count = 0;
if (priority)
count = dentry_stat.nr_unused / priority;
prune_dcache(count, -1);
}
}
void shrink_dcache_parent(struct dentry * parent)
{
int found;
while ((found = select_parent(parent)) != 0) {
prune_dcache(found);
conditional_schedule(); /* Typically sys_rmdir() */
}
}
static void shrink_dentry_inodes(int goal)
{
int found;
spin_unlock(&inode_lock);
found = select_dcache(goal, 0);
if (found < goal)
found = goal;
prune_dcache(found);
spin_lock(&inode_lock);
}
/*
* Searches the inodes list for freeable inodes,
* shrinking the dcache before (and possible after,
* if we're low)
*/
static void try_to_free_inodes(int goal)
{
/*
* First stry to just get rid of unused inodes.
*
* If we can't reach our goal that way, we'll have
* to try to shrink the dcache and sync existing
* inodes..
*/
free_inodes();
goal -= inodes_stat.nr_free_inodes;
if (goal > 0) {
spin_unlock(&inode_lock);
select_dcache(goal, 0);
prune_dcache(goal);
spin_lock(&inode_lock);
sync_all_inodes();
free_inodes();
}
}
/*
* This is called from kswapd when we think we need some
* more memory, but aren't really sure how much. So we
* carefully try to free a _bit_ of our dcache, but not
* too much.
*
* Priority:
* 0 - very urgent: shrink everything
* ...
* 6 - base-level: try to shrink a bit.
*/
int shrink_dcache_memory(int priority, unsigned int gfp_mask)
{
int count = 0;
/*
* Nasty deadlock avoidance.
*
* ext2_new_block->getblk->GFP->shrink_dcache_memory->prune_dcache->
* prune_one_dentry->dput->dentry_iput->iput->inode->i_sb->s_op->
* put_inode->ext2_discard_prealloc->ext2_free_blocks->lock_super->
* DEADLOCK.
*
* We should make sure we don't hold the superblock lock over
* block allocations, but for now:
*/
if (!(gfp_mask & __GFP_FS))
return 0;
count = dentry_stat.nr_unused / priority;
prune_dcache(count);
return kmem_cache_shrink(dentry_cache);
}
/*
* This is called from kswapd when we think we need some
* more memory, but aren't really sure how much. So we
* carefully try to free a _bit_ of our dcache, but not
* too much.
*
* Priority:
* 0 - very urgent: shrink everything
* ...
* 6 - base-level: try to shrink a bit.
*/
void shrink_dcache_memory(int priority, unsigned int gfp_mask)
{
prune_dcache(0);
}
