From: David Howells <dhowells@redhat.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: dhowells@redhat.com, Peter Zijlstra <peterz@infradead.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-arch <linux-arch@vger.kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Ingo Molnar <mingo@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: cmpxchg and x86 flags output
Date: Wed, 22 Jun 2016 17:14:23 +0100 [thread overview]
Message-ID: <16406.1466612063@warthog.procyon.org.uk> (raw)
In-Reply-To: <7d1c236f-80d1-2c58-be0e-6676769636b3@zytor.com>
H. Peter Anvin <hpa@zytor.com> wrote:
> So how do we make this move forward?
Getting my API additions in is relatively straightforward, I think. The
whether-or-notness of the cmpxchg operation succeeding can be calculated by
comparing the original value read from memory with the value-to-be-replaced
inside the API function.
This can later be replaced with the boolean output from the CMPXCHG
instruction, the branch target from the LL/SC skipping or the result of the
intrinsics.
David
next prev parent reply other threads:[~2016-06-22 16:14 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-14 23:53 cmpxchg and x86 flags output H. Peter Anvin
2016-06-15 8:50 ` Peter Zijlstra
2016-06-16 22:21 ` H. Peter Anvin
2016-06-21 9:06 ` David Howells
2016-06-21 17:00 ` H. Peter Anvin
2016-06-21 17:24 ` H. Peter Anvin
2016-06-22 0:09 ` H. Peter Anvin
2016-06-22 16:14 ` David Howells [this message]
2016-08-19 17:22 ` H. Peter Anvin
2016-08-22 15:13 ` David Howells
2016-06-22 16:11 ` David Howells
2016-06-22 16:36 ` H. Peter Anvin
2016-06-22 17:11 ` Linus Torvalds
2016-06-22 17:49 ` H. Peter Anvin
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