rhashtable: Use __vmalloc with GFP_ATOMIC for table allocation

When an rhashtable user pounds rhashtable hard with back-to-back
insertions we may end up growing the table in GFP_ATOMIC context.
Unfortunately when the table reaches a certain size this often
fails because we don't have enough physically contiguous pages
to hold the new table.

Eric Dumazet suggested (and in fact wrote this patch) using
__vmalloc instead which can be used in GFP_ATOMIC context.

Reported-by: Phil Sutter <phil@nwl.cc>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu 2015-12-04 22:39:56 +08:00 committed by David S. Miller
parent 6a61d4dbf4
commit d3716f18a7

View File

@ -120,8 +120,9 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER) ||
gfp != GFP_KERNEL)
tbl = kzalloc(size, gfp | __GFP_NOWARN | __GFP_NORETRY);
if (tbl == NULL && gfp == GFP_KERNEL)
tbl = vzalloc(size);
if (tbl == NULL)
tbl = __vmalloc(size, gfp | __GFP_HIGHMEM | __GFP_ZERO,
PAGE_KERNEL);
if (tbl == NULL)
return NULL;