From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: Re: [RFC PATCH v11 for 4.15 01/24] Restartable sequences system call
Date: Thu, 16 Nov 2017 17:32:18 +0100
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To: Mathieu Desnoyers <mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org>
Cc: "Paul E. McKenney" <paulmck-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>, Boqun Feng <boqun.feng-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>, Dave Watson <davejwatson-b10kYP2dOMg@public.gmane.org>, linux-kernel <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, linux-api <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Paul Turner <pjt-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>, Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>, Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>, Andrew Hunter <ahh-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Andi Kleen <andi-Vw/NltI1exuRpAAqCnN02g@public.gmane.org>, Chris Lameter <cl-vYTEC60ixJUAvxtiuMwx3w@public.gmane.org>, Ben Maurer <bmaurer-b10kYP2dOMg@public.gmane.org>, rostedt <rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org>, Josh Triplett <josh-iaAMLnmF4UmaiuxdJuQwMA@public.gmane.org>, Linus Torvalds <torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Catalin Marinas <catalin.marinas-5wv7dgnIgG8@public.gmane.org>, Will Deacon <will>
List-Id: linux-api@vger.kernel.org

On Thu, Nov 16, 2017 at 04:27:07PM +0000, Mathieu Desnoyers wrote:
> ----- On Nov 16, 2017, at 11:18 AM, Peter Zijlstra peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org wrote:
> 
> > On Tue, Nov 14, 2017 at 03:03:51PM -0500, Mathieu Desnoyers wrote:
> >> @@ -977,6 +978,13 @@ struct task_struct {
> >>  	unsigned long			numa_pages_migrated;
> >>  #endif /* CONFIG_NUMA_BALANCING */
> >>  
> >> +#ifdef CONFIG_RSEQ
> >> +	struct rseq __user *rseq;
> >> +	u32 rseq_len;
> >> +	u32 rseq_sig;
> >> +	bool rseq_preempt, rseq_signal, rseq_migrate;
> > 
> > No bool please. Use something that has a defined size in ILP32/LP64.
> > _Bool makes it absolutely impossible to speculate on structure layout
> > across architectures.
> 
> I should as well make all those a bitmask within a "u32 rseq_event_mask" then,
> sounds fair ?

Sure, whatever works and isn't _Bool ;-)