diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/cassini.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/net/cassini.c b/drivers/net/cassini.c index 83768df2780..f1936d51b45 100644 --- a/drivers/net/cassini.c +++ b/drivers/net/cassini.c @@ -576,6 +576,18 @@ static void cas_spare_recover(struct cas *cp, const gfp_t flags) list_for_each_safe(elem, tmp, &list) { cas_page_t *page = list_entry(elem, cas_page_t, list); + /* + * With the lockless pagecache, cassini buffering scheme gets + * slightly less accurate: we might find that a page has an + * elevated reference count here, due to a speculative ref, + * and skip it as in-use. Ideally we would be able to reclaim + * it. However this would be such a rare case, it doesn't + * matter too much as we should pick it up the next time round. + * + * Importantly, if we find that the page has a refcount of 1 + * here (our refcount), then we know it is definitely not inuse + * so we can reuse it. + */ if (page_count(page->buffer) > 1) continue; |