Improve zs_unmap_object() performance by adding a fast path for
objects that don't span pages.
Signed-off-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx>
---
drivers/staging/zsmalloc/zsmalloc-main.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c
index a7a6f22..4942d41 100644
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ b/drivers/staging/zsmalloc/zsmalloc-main.c
@@ -774,6 +774,7 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle)
}
zs_copy_map_object(area->vm_buf, page, off, class->size);
+ area->vm_addr = NULL;
return area->vm_buf;
}
EXPORT_SYMBOL_GPL(zs_map_object);
@@ -788,6 +789,14 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
struct size_class *class;
struct mapping_area *area;
+ area = &__get_cpu_var(zs_map_area);
+ if (area->vm_addr) {
+ /* single-page object fastpath */
+ kunmap_atomic(area->vm_addr);
+ put_cpu_var(zs_map_area);
+ return;
+ }
+
BUG_ON(!handle);
obj_handle_to_location(handle, &page, &obj_idx);
@@ -795,11 +804,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
class = &pool->size_class[class_idx];
off = obj_idx_to_offset(page, obj_idx, class->size);
- area = &__get_cpu_var(zs_map_area);
- if (off + class->size <= PAGE_SIZE)
- kunmap_atomic(area->vm_addr);
- else
- zs_copy_unmap_object(area->vm_buf, page, off, class->size);
+ zs_copy_unmap_object(area->vm_buf, page, off, class->size);
put_cpu_var(zs_map_area);
}
EXPORT_SYMBOL_GPL(zs_unmap_object);
--
1.7.9.5
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