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    SubjectRe: [RFC PATCH] type safe allocator
    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?

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