lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Sat, 23 Apr 2016 04:37:36 +0200
From:	Peter Zijlstra <>
To:	Boqun Feng <>
Cc:	Will Deacon <>,,,,,,
Subject: Re: [RFC][PATCH 3/3] locking,arm64: Introduce cmpwait()

On Sat, Apr 23, 2016 at 12:08:57AM +0800, Boqun Feng wrote:
> How about replace smp_rmb() with a smp_acquire_barrier__after_cmpwait()?
> This barrier is designed to provide an ACQUIRE ordering when combining a
> cmpwait() .

That's a horrible name for a barrier :-)

> And cmpwait() only has minimal ordering guarantee, but if it is actually
> an ACQUIRE, then the corresponding smp_acquire_barrier__after_cmpwait()
> is just empty.
> We might need this special barrier on ppc, because we can implement it
> with "isync" given that cmpwait() has control dependency and ctrl+isync
> is ACQUIRE on ppc.
> Thoughts?

Provide a PPC specific smp_cond_load_acquire() using ISYNC ?

Powered by blists - more mailing lists