Re: would a mutex_wait be useful?

[Mindaugas Rasiukevicius <rmind%NetBSD.org@localhost>]

Mindaugas Rasiukevicius <rmind%NetBSD.org@localhost> wrote:
> Matt Thomas <matt%3am-software.com@localhost> wrote:
> > > Where/when do you need interruptible mutex?
> > 
> > I was replacing code in arm32/mem.c with a home grown lock with  
> > mutex_enter.
> > Relatively easy to do except it no longer does PCATCH.
> 
> I agree with Antti that code asks for condvar(9), at least.

Actually, taken a look at arm32/mem.c again, no need for condvar(9). If there
is a contention on mm_lock, hashed locks would help. Is it worth?

You probably was intended to set the D_MPSAFE flag for mem_cdevsw. Note that
this wont be atomic then:

if (zeropage == NULL) {
        zeropage = (void *)
            malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
        memset(zeropage, 0, PAGE_SIZE);
}

-- 
Best regards,
Mindaugas