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Subject[PATCH 2/3] Adjust the comment on get_order() to describe the size==0 case [ver #2]
Date
Adjust the comment on get_order() to note that the result of passing a size of
0 results in an undefined value.

Signed-off-by: David Howells <dhowells@redhat.com>
---

include/asm-generic/getorder.h | 23 ++++++++++++++++++++++-
1 files changed, 22 insertions(+), 1 deletions(-)

diff --git a/include/asm-generic/getorder.h b/include/asm-generic/getorder.h
index 67e7245..76e9687 100644
--- a/include/asm-generic/getorder.h
+++ b/include/asm-generic/getorder.h
@@ -5,7 +5,28 @@

#include <linux/compiler.h>

-/* Pure 2^n version of get_order */
+/**
+ * get_order - Determine the allocation order of a memory size
+ * @size: The size for which to get the order
+ *
+ * Determine the allocation order of a particular sized block of memory. This
+ * is on a logarithmic scale, where:
+ *
+ * 0 -> 2^0 * PAGE_SIZE and below
+ * 1 -> 2^1 * PAGE_SIZE to 2^0 * PAGE_SIZE + 1
+ * 2 -> 2^2 * PAGE_SIZE to 2^1 * PAGE_SIZE + 1
+ * 3 -> 2^3 * PAGE_SIZE to 2^2 * PAGE_SIZE + 1
+ * 4 -> 2^4 * PAGE_SIZE to 2^3 * PAGE_SIZE + 1
+ * ...
+ *
+ * The order returned is used to find the smallest allocation granule required
+ * to hold an object of the specified size.
+ *
+ * The result is undefined if the size is 0.
+ *
+ * This function may be used to initialise variables with compile time
+ * evaluations of constants.
+ */
static inline __attribute_const__ int get_order(unsigned long size)
{
int order;


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