[PATCH 4/5] IB/mthca: allocate mthca_array memory with kzalloc()

["Mike Rapoport (Microsoft)" <rppt@kernel.org>]

mthca_array is essentially a sparse array of pointers and there is no
need to allocate its memory using page allocator.

kmalloc() provides a better API that does not require ugly casts and
kfree() does not need to know the size of the freed object.

Performance difference between kmalloc() and __get_free_pages() is not
measurable as both allocators take an object/page from a per-CPU list for
fast path allocations.

For the slow path the performance is anyway determined by the amount of
reclaim involved rather than by what allocator is used.

Replace use of get_zeroed_page() with kzalloc() and free_page() with
kfree().

Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
 drivers/infiniband/hw/mthca/mthca_allocator.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/hw/mthca/mthca_allocator.c b/drivers/infiniband/hw/mthca/mthca_allocator.c
index dedc301235a0..117a070e784e 100644
--- a/drivers/infiniband/hw/mthca/mthca_allocator.c
+++ b/drivers/infiniband/hw/mthca/mthca_allocator.c
@@ -126,7 +126,7 @@ int mthca_array_set(struct mthca_array *array, int index, void *value)
 
 	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
 	if (!array->page_list[p].page)
-		array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);
+		array->page_list[p].page = kzalloc(PAGE_SIZE, GFP_ATOMIC);
 
 	if (!array->page_list[p].page)
 		return -ENOMEM;
@@ -142,7 +142,7 @@ void mthca_array_clear(struct mthca_array *array, int index)
 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
 
 	if (--array->page_list[p].used == 0) {
-		free_page((unsigned long) array->page_list[p].page);
+		kfree(array->page_list[p].page);
 		array->page_list[p].page = NULL;
 	} else
 		array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;
@@ -174,7 +174,7 @@ void mthca_array_cleanup(struct mthca_array *array, int nent)
 	int i;
 
 	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
-		free_page((unsigned long) array->page_list[i].page);
+		kfree(array->page_list[i].page);
 
 	kfree(array->page_list);
 }

-- 
2.53.0