diff options
Diffstat (limited to 'drivers/md/dm-crypt.c')
| -rw-r--r-- | drivers/md/dm-crypt.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 70ae6f3aede9..2aa4acd33af3 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -2643,7 +2643,12 @@ static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) struct crypt_config *cc = pool_data; struct page *page; - if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) && + /* + * Note, percpu_counter_read_positive() may over (and under) estimate + * the current usage by at most (batch - 1) * num_online_cpus() pages, + * but avoids potential spinlock contention of an exact result. + */ + if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && likely(gfp_mask & __GFP_NORETRY)) return NULL; |