linux-kernel - Re: [PATCH 1/3] kernel/sched: introduce vcpu preempted check interface

lists.openwall.net		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 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 27 Jun 2016 16:02:55 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Pan Xinhui <xinhui.pan@...ux.vnet.ibm.com>
Cc:	linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
	paulmck@...ux.vnet.ibm.com, mingo@...hat.com, mpe@...erman.id.au,
	paulus@...ba.org, benh@...nel.crashing.org, Waiman.Long@....com,
	boqun.feng@...il.com, will.deacon@....com, dave@...olabs.net
Subject: Re: [PATCH 1/3] kernel/sched: introduce vcpu preempted check
 interface

On Mon, Jun 27, 2016 at 04:00:43PM +0200, Peter Zijlstra wrote:
> On Mon, Jun 27, 2016 at 01:41:28PM -0400, Pan Xinhui wrote:
> > +++ b/include/linux/sched.h
> > @@ -3293,6 +3293,15 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
> >  
> >  #endif /* CONFIG_SMP */
> >  
> > +#ifdef arch_vcpu_is_preempted
> > +static inline bool vcpu_is_preempted(int cpu)
> > +{
> > +	return arch_vcpu_is_preempted(cpu);
> > +}
> > +#else
> > +#define vcpu_is_preempted(cpu)	false
> > +#endif
> 
> #ifndef vcpu_is_preempted
> #define vcpu_is_preempted(cpu)		(false)
> #endif
> 
> Is so much simpler...
> 
> Also, please Cc the virt list so that other interested parties can
> comment, and maybe also the s390 folks.

And before you hurry off to post again, add a patch doing
mutex_spin_on_owner() and rwsem_spin_in_owner().