From: "H. Peter Anvin" <hpa@zytor.com>
To: Waiman Long <waiman.long@hp.com>, Jason Low <jason.low2@hp.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Peter Zijlstra <peterz@infradead.org>,
jejb@parisc-linux.org, deller@gmx.de,
John David Anglin <dave.anglin@bell.net>,
linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org,
paulmck@linux.vnet.ibm.com, chegu_vinod@hp.com,
tglx@linutronix.de, riel@redhat.com, akpm@linux-foundation.org,
davidlohr@hp.com, andi@firstfloor.org, aswin@hp.com,
scott.norton@hp.com
Subject: Re: [PATCH v2] introduce atomic_pointer to fix a race condition in cancelable mcs spinlocks
Date: Mon, 02 Jun 2014 10:38:18 -0700 [thread overview]
Message-ID: <538CB68A.6030408@zytor.com> (raw)
In-Reply-To: <538CB389.5080108@hp.com>
On 06/02/2014 10:25 AM, Waiman Long wrote:
>
> Doing an xchg is a very expensive operation compared with ACCESS_ONCE. I
> will not suggest doing that to make it right for PA-RISC at the expense
> of performance in other architectures.
>
And of course, this gets into the toxic question: what are reasonable
minimum requirements for Linux? How far do we need to stretch to
support niche architectures which have very small (Linux) userbases?
-hpa
prev parent reply other threads:[~2014-06-02 17:39 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-01 17:53 [PATCH] fix a race condition in cancelable mcs spinlocks Mikulas Patocka
2014-06-01 19:20 ` Peter Zijlstra
2014-06-01 20:46 ` John David Anglin
2014-06-01 21:30 ` Peter Zijlstra
2014-06-01 21:46 ` Paul E. McKenney
2014-06-02 9:19 ` Mikulas Patocka
2014-06-02 13:24 ` Paul E. McKenney
2014-06-02 15:57 ` Mikulas Patocka
2014-06-02 16:39 ` Paul E. McKenney
2014-06-02 19:56 ` James Bottomley
2014-06-03 7:56 ` Peter Zijlstra
2014-06-04 12:53 ` Mikulas Patocka
2014-06-02 13:58 ` Mikulas Patocka
2014-06-02 14:02 ` Mikulas Patocka
2014-06-02 15:39 ` John David Anglin
2014-06-02 10:34 ` Mikulas Patocka
2014-06-02 14:14 ` Waiman Long
2014-06-02 15:27 ` Jason Low
2014-06-02 16:00 ` [PATCH v2] introduce atomic_pointer to " Mikulas Patocka
2014-06-02 16:25 ` Peter Zijlstra
2014-06-02 16:30 ` Peter Zijlstra
2014-06-02 16:46 ` Paul E. McKenney
2014-06-02 17:33 ` Waiman Long
2014-06-02 20:05 ` Peter Zijlstra
2014-06-02 20:22 ` Linus Torvalds
2014-06-02 21:02 ` Paul E. McKenney
2014-06-02 21:12 ` Linus Torvalds
2014-06-02 22:08 ` Paul E. McKenney
2014-06-02 22:44 ` Eric Dumazet
2014-06-02 23:17 ` Paul E. McKenney
2014-06-02 23:53 ` Eric Dumazet
2014-06-03 0:28 ` Paul E. McKenney
2014-06-02 22:55 ` Linus Torvalds
2014-06-03 16:48 ` Paul E. McKenney
2014-06-03 7:54 ` Peter Zijlstra
2014-06-02 20:24 ` James Bottomley
2014-06-02 16:43 ` Paul E. McKenney
2014-06-02 17:14 ` James Bottomley
2014-06-02 17:29 ` Waiman Long
2014-06-02 17:09 ` Linus Torvalds
2014-06-02 17:12 ` Davidlohr Bueso
2014-06-02 17:42 ` Waiman Long
2014-06-02 20:46 ` Mikulas Patocka
2014-06-02 20:53 ` Linus Torvalds
2014-06-02 21:12 ` Mikulas Patocka
2014-06-03 7:36 ` Peter Zijlstra
2014-06-03 11:14 ` Mikulas Patocka
2014-06-03 13:24 ` Peter Zijlstra
2014-06-03 14:18 ` Mikulas Patocka
2014-06-03 14:07 ` Paul E. McKenney
2014-06-03 15:09 ` Peter Zijlstra
2014-06-03 15:56 ` Paul E. McKenney
2014-06-03 7:20 ` Peter Zijlstra
2014-06-02 21:03 ` Paul E. McKenney
2014-06-06 15:06 ` Peter Zijlstra
2014-06-06 15:15 ` Paul E. McKenney
2014-06-06 15:42 ` Davidlohr Bueso
2014-06-02 16:50 ` Jason Low
2014-06-02 17:03 ` Paul E. McKenney
2014-06-02 17:25 ` Waiman Long
2014-06-02 17:38 ` H. Peter Anvin [this message]
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