From 103123305c4f695cbb11555d51a32ea14d6bed05 Mon Sep 17 00:00:00 2001 From: Seth Jennings Date: Mon, 2 Jul 2012 16:15:50 -0500 Subject: [PATCH] staging: zsmalloc: add single-page object fastpath in unmap Improve zs_unmap_object() performance by adding a fast path for objects that don't span pages. Signed-off-by: Seth Jennings Signed-off-by: Greg Kroah-Hartman --- 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 a7a6f225bbff..4942d419074b 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);