From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [RFC PATCH for 4.17 02/21] rseq: Introduce restartable
 sequences system call (v12)
Date: Wed, 28 Mar 2018 10:26:14 -0400 (EDT)
Message-ID: <220077125.2034.1522247174476.JavaMail.zimbra@efficios.com>
References: <20180327160542.28457-1-mathieu.desnoyers@efficios.com> <20180327160542.28457-3-mathieu.desnoyers@efficios.com> <20180328112225.GT4043@hirez.programming.kicks-ass.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20180328112225.GT4043@hirez.programming.kicks-ass.net>
Sender: linux-kernel-owner@vger.kernel.org
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, Boqun Feng <boqun.feng@gmail.com>, Andy Lutomirski <luto@amacapital.net>, Dave Watson <davejwatson@fb.com>, linux-kernel <linux-kernel@vger.kernel.org>, linux-api <linux-api@vger.kernel.org>, Paul Turner <pjt@google.com>, Andrew Morton <akpm@linux-foundation.org>, Russell King <linux@arm.linux.org.uk>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, Andrew Hunter <ahh@google.com>, Andi Kleen <andi@firstfloor.org>, Chris Lameter <cl@linux.com>, Ben Maurer <bmaurer@fb.com>, rostedt <rostedt@goodmis.org>, Josh Triplett <josh@joshtriplett.org>, Linus Torvalds <torvalds@linux-foundation.org>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will>
List-Id: linux-api@vger.kernel.org

----- On Mar 28, 2018, at 7:22 AM, Peter Zijlstra peterz@infradead.org wrote:

> On Tue, Mar 27, 2018 at 12:05:23PM -0400, Mathieu Desnoyers wrote:
>> +/*
>> + * struct rseq_cs is aligned on 4 * 8 bytes to ensure it is always
>> + * contained within a single cache-line. It is usually declared as
>> + * link-time constant data.
>> + */
>> +struct rseq_cs {
>> +	/* Version of this structure. */
>> +	uint32_t version;
>> +	/* enum rseq_cs_flags */
>> +	uint32_t flags;
>> +	LINUX_FIELD_u32_u64(start_ip);
>> +	/* Offset from start_ip. */
>> +	LINUX_FIELD_u32_u64(post_commit_offset);
>> +	LINUX_FIELD_u32_u64(abort_ip);
>> +} __attribute__((aligned(4 * sizeof(uint64_t))));
> 
> What's with the uint32_t ? The normal Linux API type is __u32 afaik.

Will fix. Working on both kernel and user-space code in parallel kind
of does that to the brain. ;-)

Thanks,

Mathieu


-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com