Re: [Xen-devel] [RFC v3 07/13] tables.h: add linker table support

["H. Peter Anvin" <hpa@xxxxxxxxx>]

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On July 27, 2016 4:02:18 PM PDT, "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx> wrote:
>On Tue, Jul 26, 2016 at 12:30:14AM +0900, Masami Hiramatsu wrote:
>> On Fri, 22 Jul 2016 14:24:41 -0700
>> "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx> wrote:
>> 
>> > +/**
>> > + * LINKTABLE_RUN_ALL - iterate and run through all entries on a
>linker table
>> > + *
>> > + * @tbl: linker table
>> > + * @func: structure name for the function name we want to call.
>> > + * @args...: arguments to pass to func
>> > + *
>> > + * Example usage:
>> > + *
>> > + *   LINKTABLE_RUN_ALL(frobnicator_fns, some_run,);
>> > + */
>> > +#define LINKTABLE_RUN_ALL(tbl, func, args...)                             
>> > \
>> > +do {                                                                      
>> > \
>> > +  size_t i;                                                       \
>> > +  for (i = 0; i < LINUX_SECTION_SIZE(tbl); i++)                   \
>> > +          (tbl[i]).func (args);                                   \
>> > +} while (0);
>> > +
>> > +/**
>> > + * LINKTABLE_RUN_ERR - run each linker table entry func and return
>error if any
>> > + *
>> > + * @tbl: linker table
>> > + * @func: structure name for the function name we want to call.
>> > + * @args...: arguments to pass to func
>> > + *
>> > + * Example usage:
>> > + *
>> > + *   unsigned int err = LINKTABLE_RUN_ERR(frobnicator_fns,
>some_run,);
>> > + */
>> > +#define LINKTABLE_RUN_ERR(tbl, func, args...)                             
>> > \
>> > +({                                                                        
>> > \
>> > +  size_t i;                                                       \
>> > +  int err = 0;                                                    \
>> > +  for (i = 0; !err && i < LINUX_SECTION_SIZE(tbl); i++)           \
>> > +          err = (tbl[i]).func (args);                             \
>> > +          err; \
>> > +})
>> 
>> These iteration APIs are a bit dangerous, at least for these APIs
>we'd better change
>> name like as FUNCTABLE_RUN etc. because LINKTABLE can contain not
>only function address
>> but also some data (or address of data).
>
>Sure will do, thanks for the review.
>
>  Luis

I don't know if they are dangerous.  Keep in mind C type checking is still 
present.
-- 
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