From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 1 Aug 2007 22:33:07 -0700 (PDT) From: Christoph Lameter Subject: Re: [RFC PATCH] type safe allocator In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Miklos Szeredi Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, torvalds@linux-foundation.org List-ID: On Wed, 1 Aug 2007, Miklos Szeredi wrote: > I wonder why we don't have type safe object allocators a-la new() in > C++ or g_new() in glib? > > fooptr = k_new(struct foo, GFP_KERNEL); > > is nicer and more descriptive than > > fooptr = kmalloc(sizeof(*fooptr), GFP_KERNEL); > > and more safe than > > fooptr = kmalloc(sizeof(struct foo), GFP_KERNEL); > > And we have zillions of both variants. Hmmm yes I think that would be good. However, please clean up the naming. The variant on zeroing on zering get to be too much. > + * k_new - allocate given type object > + * @type: the type of the object to allocate > + * @flags: the type of memory to allocate. > + */ > +#define k_new(type, flags) ((type *) kmalloc(sizeof(type), flags)) kalloc? > + > + * k_new0 - allocate given type object, zero out allocated space > + * @type: the type of the object to allocate > + * @flags: the type of memory to allocate. > + */ > +#define k_new0(type, flags) ((type *) kzalloc(sizeof(type), flags)) A new notation for zeroing! This is equivalent to kalloc(type, flags | __GFP_ZERO) maybe define new GFP_xxx instead? > +/** > + * k_new_array - allocate array of given type object > + * @type: the type of the object to allocate > + * @len: the length of the array > + * @flags: the type of memory to allocate. > + */ > +#define k_new_array(type, len, flags) \ > + ((type *) kmalloc(sizeof(type) * (len), flags)) We already have array initializations using kcalloc. > +#define k_new0_array(type, len, flags) \ > + ((type *) kzalloc(sizeof(type) * (len), flags)) Same as before. I do not see any _node variants? How about the following minimal set kmalloc(size, flags) kalloc(struct, flags) kmalloc_node(size, flags, node) kalloc_node(struct, flags, node) The array variants translate into kmalloc anyways and are used in an inconsistent manner. Sometime this way sometimes the other. Leave them? kcalloc(n, size, flags) == kmalloc(size, flags) Then kzalloc is equivalent to adding the __GFP_ZERO flag. Thus kzalloc(size, flags) == kmalloc(size, flags | __GFPZERO) If you define a new flag like GFP_ZERO_ATOMIC and GFP_ZERO_KERNEL you could do kalloc(struct, GFP_ZERO_KERNEL) instead of adding new variants? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org