On Wed, Nov 19, 2014 at 12:18 AM, Masao Uebayashi <uebay...@gmail.com> wrote:
> On Mon, Nov 17, 2014 at 7:03 PM, Ryota Ozaki <ozak...@netbsd.org> wrote:
>> - http://www.netbsd.org/~ozaki-r/psz-ifnet.diff
>
> IFNET_RENTER();
> IFNET_FOREACH() {
> if->if_watchdog();
> }
> IFNET_REXIT();
>
> This is not safe; if_watchdog() may resend packets, too slow operation
> to do in critical section.
Sure.
>
> I think you need to allocate a global array if_watchdog_t
> **if_slowtimo_watchdog, like ifindex2ifnet, which grows and can store
> pointers of if_watchdog of all interfaces, and do:
>
> IFNET_RENTER();
> i = 0;
> IFNET_FOREACH() {
> if_slowtimo_watchdog[i++] = if->if_watchdog;
> }
> IFNET_REXIT();
> for (j = 0; j < i; j++) {
> (*(if_slowtimo_watchdog[j]))();
> }
It seems incomplete. We have to store both a function
pointer and an ifp for each ifnet. Additionally we have to
prevent the ifps from being freed during executing if_watchdog
functions. So a complete version would be:
IFNET_FOREACH() {
if_watchdog_funcs[i++] = ifp->if_watchdog;
if_watchdog_ifps[i++] = ifp;
refcount_hold(ifp->if_refcount);
}
IFNET_REXIT();
for (j = 0; j < i; j++) {
(*(if_watchdog_funcs[j]))(if_watchdog_ifps[j]);
ifput(ifps[j]);
}
Weird :-/
ozaki-r
