treewide: use kv[mz]alloc* rather than opencoded variants

There are many code paths opencoding kvmalloc.  Let's use the helper
instead.  The main difference to kvmalloc is that those users are usually
not considering all the aspects of the memory allocator.  E.g.  allocation
requests <= 32kB (with 4kB pages) are basically never failing and invoke
OOM killer to satisfy the allocation.  This sounds too disruptive for
something that has a reasonable fallback - the vmalloc.  On the other hand
those requests might fallback to vmalloc even when the memory allocator
would succeed after several more reclaim/compaction attempts previously.
There is no guarantee something like that happens though.

This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.

Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 1 insertions, 4 deletions

diff --git a/mm/frame_vector.c b/mm/frame_vector.c
index db77dcb38afd..72ebec18629c 100644
--- a/mm/frame_vector.c
+++ b/mm/frame_vector.c
@@ -200,10 +200,7 @@ struct frame_vector *frame_vector_create(unsigned int nr_frames)
 	 * Avoid higher order allocations, use vmalloc instead. It should
 	 * be rare anyway.
 	 */
-	if (size <= PAGE_SIZE)
-		vec = kmalloc(size, GFP_KERNEL);
-	else
-		vec = vmalloc(size);
+	vec = kvmalloc(size, GFP_KERNEL);
 	if (!vec)
 		return NULL;
 	vec->nr_allocated = nr_frames;