don't remove from shrink list in select_collect()

If we find something already on a shrink list, just increment
data->found and do nothing else.  Loops in shrink_dcache_parent() and
check_submounts_and_drop() will do the right thing - everything we
did put into our list will be evicted and if there had been nothing,
but data->found got non-zero, well, we have somebody else shrinking
those guys; just try again.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-05-03 00:02:25 -04:00
parent 41edf278fc
commit fe91522a7b

View File

@ -1229,34 +1229,23 @@ static enum d_walk_ret select_collect(void *_data, struct dentry *dentry)
if (data->start == dentry)
goto out;
/*
* move only zero ref count dentries to the dispose list.
*
* Those which are presently on the shrink list, being processed
* by shrink_dentry_list(), shouldn't be moved. Otherwise the
* loop in shrink_dcache_parent() might not make any progress
* and loop forever.
*/
if (dentry->d_lockref.count) {
dentry_lru_del(dentry);
} else if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) {
/*
* We can't use d_lru_shrink_move() because we
* need to get the global LRU lock and do the
* LRU accounting.
*/
d_lru_del(dentry);
d_shrink_add(dentry, &data->dispose);
if (dentry->d_flags & DCACHE_SHRINK_LIST) {
data->found++;
ret = D_WALK_NORETRY;
} else {
if (dentry->d_flags & DCACHE_LRU_LIST)
d_lru_del(dentry);
if (!dentry->d_lockref.count) {
d_shrink_add(dentry, &data->dispose);
data->found++;
}
}
/*
* We can return to the caller if we have found some (this
* ensures forward progress). We'll be coming back to find
* the rest.
*/
if (data->found && need_resched())
ret = D_WALK_QUIT;
if (!list_empty(&data->dispose))
ret = need_resched() ? D_WALK_QUIT : D_WALK_NORETRY;
out:
return ret;
}