From af4e5a218e18ad588d60a4f9d6f8fb5db1a32587 Mon Sep 17 00:00:00 2001 From: Pekka J Enberg Date: Fri, 16 Sep 2005 19:28:11 -0700 Subject: [PATCH] [PATCH] CodingStyle: memory allocation This patch adds a new chapter on memory allocation to Documentation/CodingStyle. Signed-off-by: Pekka Enberg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/CodingStyle | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index 22e5f9036f..eb7db3c192 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -410,7 +410,26 @@ Kernel messages do not have to be terminated with a period. Printing numbers in parentheses (%d) adds no value and should be avoided. - Chapter 13: References + Chapter 13: Allocating memory + +The kernel provides the following general purpose memory allocators: +kmalloc(), kzalloc(), kcalloc(), and vmalloc(). Please refer to the API +documentation for further information about them. + +The preferred form for passing a size of a struct is the following: + + p = kmalloc(sizeof(*p), ...); + +The alternative form where struct name is spelled out hurts readability and +introduces an opportunity for a bug when the pointer variable type is changed +but the corresponding sizeof that is passed to a memory allocator is not. + +Casting the return value which is a void pointer is redundant. The conversion +from void pointer to any other pointer type is guaranteed by the C programming +language. + + + Chapter 14: References The C Programming Language, Second Edition by Brian W. Kernighan and Dennis M. Ritchie. -- 2.39.5