On Fri, 29 Aug 2008 15:32:58 -0700

"Yinghai Lu"  wrote:
> On Fri, Aug 29, 2008 at 3:20 PM, Andrew Morton

quoted text
>  wrote:

> > On Fri, 29 Aug 2008 15:07:49 -0700

> > Yinghai Lu  wrote:

> >

> >> +             printk(KERN_DEBUG "per_cpu_dyn_array %pF ==> [%#lx - %#lx]\n",

> >> +                     da->name, phys, phys + size);

> >

> > This:

> >

> > struct dyn_array {

> >        void **name;

> >

> > is a bit confusing.  One normally expects a variable called "name" to

> > point at a character string.

> >

> > What _does_ this thing point at?  There are no code comments which I

> > can find, it's unobvious from the source code, the type is the

> > information-free void** and the identifier is misleading.

> >

> > I find that documenting the data structures is the best way of making

> > code understandable (and hence maintainable).

>

> struct dyn_array {

>         void **name;

>         unsigned long size;

>         unsigned int *nr;

>         unsigned long align;

>         void (*init_work)(void *);

> };

> extern struct dyn_array *__dyn_array_start[], *__dyn_array_end[];

> extern struct dyn_array *__per_cpu_dyn_array_start[],

> *__per_cpu_dyn_array_end[];

>

> #define DEFINE_DYN_ARRAY_ADDR(nameX, addrX, sizeX, nrX, alignX, init_workX) \

>                 static struct dyn_array __dyn_array_##nameX __initdata = \

>                 {       .name = (void **)&(nameX),\

>                         .size = sizeX,\

>                         .nr   = &(nrX),\

>                         .align = alignX,\

>                         .init_work = init_workX,\

>                 }; \

>                 static struct dyn_array *__dyn_array_ptr_##nameX __used \

>                 __attribute__((__section__(".dyn_array.init"))) = \

>                         &__dyn_array_##nameX

>

> #define DEFINE_DYN_ARRAY(nameX, sizeX, nrX, alignX, init_workX) \

>         DEFINE_DYN_ARRAY_ADDR(nameX, nameX, sizeX, nrX, alignX, init_workX)

>

> and use is

>

> struct irq_desc *sparse_irqs;

> DEFINE_DYN_ARRAY(sparse_irqs, sizeof(struct irq_desc), nr_irq_desc,

> PAGE_SIZE, init_work);

>

>

> then sparse_irqs is pointer, and .name store the address of that pointer.

>

> later use

> *da->name = phys_to_virt(phys);

> to take back the dyn address.

> 

Well yes, I have a copy of that too.
Why is it called "name"?
--

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