lkml.org 
[lkml]   [2008]   [Aug]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] dyn_array: using %pF instead of print_fn_descriptor_symbol
On Fri, Aug 29, 2008 at 3:20 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Fri, 29 Aug 2008 15:07:49 -0700
> Yinghai Lu <yhlu.kernel@gmail.com> 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.

YH


\
 
 \ /
  Last update: 2008-08-30 00:35    [W:0.344 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site