Re: [PATCH] pids: simplify do_each_task_pid/while_each_task_pid

Oleg Nesterov
2006-04-13T13:57:24Z

On 04/13, Christoph Hellwig wrote:
>
> On Thu, Apr 13, 2006 at 08:37:27PM +0400, Oleg Nesterov wrote:
> > +#define do_each_task_pid(who, type, task) \
> > + do { \
> > + struct hlist_node *pos___; \
> > + struct pid *pid___ = find_pid(who); \
> > + if (pid___ != NULL) \
> > + hlist_for_each_entry_rcu((task), pos___, \
> > + &pid___->tasks[type], pids[type].node) {
> > +
> > +#define while_each_task_pid(who, type, task) \
> > + } \
> > + } while (0)
>
> This is prtty ugly. Can't we just have a
>
> #define for_each_task_pid(task, pid, type, pos) \
> hlist_for_each_entry_rcu((task), (pos), \
> (&(pid))->tasks[type], pids[type].node) {
>
> and move the find_pid to the caller? That would make the code a whole lot
> more readable.

Then the caller should check find_pid() doesn't return NULL. But yes,
we can hide this check inside for_each_task_pid().

But what about current users of do_each_task_pid ? We can't just remove
these macros.

Oleg.