From: Ramana Radhakrishnan <ramana.radhakrishnan@arm.com>
To: David Howells <dhowells@redhat.com>,
"paulmck@linux.vnet.ibm.com" <paulmck@linux.vnet.ibm.com>
Cc: Will Deacon <Will.Deacon@arm.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
"c++std-parallel@accu.org" <c++std-parallel@accu.org>,
"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
"gcc@gcc.gnu.org" <gcc@gcc.gnu.org>,
p796231 <Peter.Sewell@cl.cam.ac.uk>,
"mark.batty@cl.cam.ac.uk" <Mark.Batty@cl.cam.ac.uk>,
Peter Zijlstra <peterz@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
Ingo Molnar <mingo@kernel.org>,
"michaelw@ca.ibm.com" <michaelw@ca.ibm.com>
Subject: Re: Compilers and RCU readers: Once more unto the breach!
Date: Wed, 20 May 2015 14:44:30 +0100 [thread overview]
Message-ID: <555C8FBE.4020505@arm.com> (raw)
In-Reply-To: <31805.1432129025@warthog.procyon.org.uk>
On 20/05/15 14:37, David Howells wrote:
> Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:
>
>> I was thinking of "y" as a simple variable, but if it is something more
>> complex, then the compiler could do this, right?
>>
>> char *x;
>>
>> y;
>> x = z;
>
> Yeah. I presume it has to maintain the ordering, though.
The scheduler for e.g. is free to reorder if it can prove there is no
dependence (or indeed side-effects for y) between insns produced for y
and `x = z'.
regards
Ramana
>
> David
>
next prev parent reply other threads:[~2015-05-20 13:44 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-20 0:55 Compilers and RCU readers: Once more unto the breach! Paul E. McKenney
2015-05-20 1:57 ` Linus Torvalds
2015-05-20 1:57 ` Linus Torvalds
2015-05-20 1:57 ` Linus Torvalds
2015-05-20 2:10 ` Linus Torvalds
2015-05-20 2:41 ` Paul E. McKenney
2015-05-20 11:47 ` Will Deacon
2015-05-20 12:15 ` Paul E. McKenney
2015-05-20 13:18 ` David Howells
2015-05-20 13:30 ` Paul E. McKenney
2015-05-20 13:37 ` David Howells
2015-05-20 13:44 ` Ramana Radhakrishnan [this message]
2015-05-20 14:03 ` Paul E. McKenney
2015-05-20 14:15 ` Ramana Radhakrishnan
2015-05-20 15:12 ` Paul E. McKenney
2015-05-20 15:46 ` David Howells
2015-05-20 14:02 ` [c++std-parallel-1624] " Paul E. McKenney
2015-05-20 15:46 ` Will Deacon
2015-05-20 15:54 ` Andrew Haley
2015-05-20 18:16 ` [c++std-parallel-1632] " Paul E. McKenney
2015-05-21 14:22 ` Michael Matz
2015-05-21 15:10 ` Paul E. McKenney
2015-05-21 16:17 ` Michael Matz
2015-05-21 18:37 ` Paul E. McKenney
2015-05-20 18:16 ` Paul E. McKenney
2015-05-21 19:24 ` Will Deacon
2015-05-21 20:02 ` Paul E. McKenney
2015-05-21 20:42 ` Linus Torvalds
2015-05-21 22:02 ` Paul E. McKenney
2015-05-22 6:43 ` Ingo Molnar
2015-05-22 10:43 ` Richard Kenner
2015-05-22 13:11 ` Paul E. McKenney
2015-05-22 13:12 ` Paul E. McKenney
2015-05-26 17:37 ` [c++std-parallel-1641] " Torvald Riegel
2015-05-22 17:30 ` Will Deacon
2015-05-22 18:55 ` Paul E. McKenney
2015-05-20 2:34 ` Paul E. McKenney
2015-05-20 7:34 ` [c++std-parallel-1614] " Jens Maurer
2015-05-20 7:34 ` Jens Maurer
2015-05-20 7:34 ` Jens Maurer
2015-05-20 9:03 ` Richard Biener
2015-05-20 12:02 ` Paul E. McKenney
2015-05-20 12:01 ` [c++std-parallel-1616] " Paul E. McKenney
2015-05-26 17:08 ` [c++std-parallel-1611] " Torvald Riegel
2015-05-27 1:41 ` [c++std-parallel-1651] " Paul E. McKenney
2015-07-14 0:44 ` Paul E. McKenney
2015-09-22 17:00 ` Paul E. McKenney
[not found] ` <CAPUmR1aqV_cQWjE8qC9x2sfmW-1ocKKMtCgNbjZH0cJ-AO2WTg@mail.gmail.com>
2015-09-23 23:26 ` [c++std-parallel-2008] " Paul E. McKenney
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