Re: [TOMOYO 05/15](repost) Domain transition handler functions.

[KaiGai Kohei]

Tetsuo Handa wrote:
> James Morris wrote:
> > I'm pretty sure that the singly linked list idea has been rejected a few 
> > times.  Just use the existing API.
> Too bad...
>
> Well, is there a way to avoid read_lock when reading list?
>
> Currently, TOMOYO Linux avoids read_lock, on the assumption that
> (1) First, ptr->next is initialized with NULL.
> (2) Later, ptr->next is assigned non-NULL address.
> (3) Assigning to ptr->next is done atomically.
>
> Regards.

Is it all of the purpose for the list structure?
If so, you can apply RCU instead to avoid read lock
when scanning the list, like:

rcu_read_lock();
list_for_each_entry(...) {
    ....
}
rcu_read_unlock();

--
KaiGai Kohei <kaigai@xxxxxxxxxxxx>
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