[PATCH 14/16] mm: use alloc_pages_exact_node to implement alloc_pages_exact

From: Christoph Hellwig
Date: Fri Jun 14 2019 - 09:53:42 EST


No need to duplicate the logic over two functions that are almost the
same.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
include/linux/gfp.h | 5 +++--
mm/page_alloc.c | 39 +++++++--------------------------------
2 files changed, 10 insertions(+), 34 deletions(-)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 4274ea6bc72b..c616a23a3f81 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -530,9 +530,10 @@ extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
extern unsigned long get_zeroed_page(gfp_t gfp_mask);

-void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
void free_pages_exact(void *virt, size_t size);
-void * __meminit alloc_pages_exact_node(int nid, size_t size, gfp_t gfp_mask);
+void *alloc_pages_exact_node(int nid, size_t size, gfp_t gfp_mask);
+#define alloc_pages_exact(size, gfp_mask) \
+ alloc_pages_exact_node(NUMA_NO_NODE, size, gfp_mask)

#define __get_free_page(gfp_mask) \
__get_free_pages((gfp_mask), 0)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index dd2fed66b656..dec68bd21a71 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4859,34 +4859,6 @@ static void *make_alloc_exact(unsigned long addr, unsigned int order,
return (void *)addr;
}

-/**
- * alloc_pages_exact - allocate an exact number physically-contiguous pages.
- * @size: the number of bytes to allocate
- * @gfp_mask: GFP flags for the allocation, must not contain __GFP_COMP
- *
- * This function is similar to alloc_pages(), except that it allocates the
- * minimum number of pages to satisfy the request. alloc_pages() can only
- * allocate memory in power-of-two pages.
- *
- * This function is also limited by MAX_ORDER.
- *
- * Memory allocated by this function must be released by free_pages_exact().
- *
- * Return: pointer to the allocated area or %NULL in case of error.
- */
-void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
-{
- unsigned int order = get_order(size);
- unsigned long addr;
-
- if (WARN_ON_ONCE(gfp_mask & __GFP_COMP))
- gfp_mask &= ~__GFP_COMP;
-
- addr = __get_free_pages(gfp_mask, order);
- return make_alloc_exact(addr, order, size);
-}
-EXPORT_SYMBOL(alloc_pages_exact);
-
/**
* alloc_pages_exact_node - allocate an exact number of physically-contiguous
* pages on a node.
@@ -4894,12 +4866,15 @@ EXPORT_SYMBOL(alloc_pages_exact);
* @size: the number of bytes to allocate
* @gfp_mask: GFP flags for the allocation, must not contain __GFP_COMP
*
- * Like alloc_pages_exact(), but try to allocate on node nid first before falling
- * back.
+ * This function is similar to alloc_pages_node(), except that it allocates the
+ * minimum number of pages to satisfy the request while alloc_pages() can only
+ * allocate memory in power-of-two pages. This function is also limited by
+ * MAX_ORDER.
*
- * Return: pointer to the allocated area or %NULL in case of error.
+ * Returns a pointer to the allocated area or %NULL in case of error, memory
+ * allocated by this function must be released by free_pages_exact().
*/
-void * __meminit alloc_pages_exact_node(int nid, size_t size, gfp_t gfp_mask)
+void *alloc_pages_exact_node(int nid, size_t size, gfp_t gfp_mask)
{
unsigned int order = get_order(size);
struct page *p;
--
2.20.1