tech-kern archive
[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index][
Old Index]
Re: mutex(9) on sparc64 RMO [was Re: pserialize(9) vs. TAILQ]
On 2014年11月24日, Taylor R Campbell wrote:
> Date: 2014年11月24日 16:44:41 +0000 (UTC)
> From: Eduardo Horvath <eeh%NetBSD.org@localhost>
>
> I enhanced membar_ops with proper memory barriers and then was looking at
> the mutex code. Unfortunately, I didn't get very far. It seemed at the
> time that the mutex code has two hooks for memory barriers after the
> atomic operations, however it's missing memory barrier hooks to ensure
> consistency before accessing the lock.
>
> What exactly is the consistency you need before accessing the lock?
I know you need a `membar #Lookaside' before accessing the atomic
variable. I don't recall if other memory barriers are needed since it's
been a while since I last looked at the V9 architecture reference.
Eduardo
Home |
Main Index |
Thread Index |
Old Index