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From: David Laight <David.Laight@ACULAB.COM>
To: 'Peter Zijlstra' <peterz@infradead.org>
Cc: "linux-toolchains@vger.kernel.org"
	<linux-toolchains@vger.kernel.org>, Will Deacon <will@kernel.org>,
	Paul McKenney <paulmck@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"stern@rowland.harvard.edu" <stern@rowland.harvard.edu>,
	"parri.andrea@gmail.com" <parri.andrea@gmail.com>,
	"boqun.feng@gmail.com" <boqun.feng@gmail.com>,
	"npiggin@gmail.com" <npiggin@gmail.com>,
	"dhowells@redhat.com" <dhowells@redhat.com>,
	"j.alglave@ucl.ac.uk" <j.alglave@ucl.ac.uk>,
	"luc.maranget@inria.fr" <luc.maranget@inria.fr>,
	"akiyks@gmail.com" <akiyks@gmail.com>,
	"dlustig@nvidia.com" <dlustig@nvidia.com>,
	"joel@joelfernandes.org" <joel@joelfernandes.org>,
	"torvalds@linux-foundation.org" <torvalds@linux-foundation.org>
Subject: RE: Control Dependencies vs C Compilers
Date: Tue, 6 Oct 2020 15:07:41 +0000	[thread overview]
Message-ID: <0a0403a430b14484a026b52a5ecbbeeb@AcuMS.aculab.com> (raw)
In-Reply-To: <20201006133115.GT2628@hirez.programming.kicks-ass.net>

> Please go read memory-barriers.txt for a bunch of other examples.

My brain hurts.
It's not as though I've not known about most of this since
the first SMP capable SPARC cpus that had a 'store buffer'.
(Probably 30 years ago.)

I sometimes wonder whether compiling things like the kernel
requires a compiler mode that defaults everything (except
function locals) to 'volatile'.
Although that still does fix control dependencies.

	David

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Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)


  parent reply	other threads:[~2020-10-06 15:07 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-06 11:47 Control Dependencies vs C Compilers Peter Zijlstra
2020-10-06 12:37 ` David Laight
2020-10-06 12:49   ` Willy Tarreau
2020-10-06 13:31   ` Peter Zijlstra
2020-10-06 14:23     ` stern
2020-10-06 14:43       ` Peter Zijlstra
2020-10-06 15:16         ` Nick Clifton
2020-10-06 15:37           ` David Laight
2020-10-06 15:50             ` Paul E. McKenney
2020-10-06 16:10               ` Willy Tarreau
2020-10-06 16:22                 ` David Laight
2020-10-06 16:31                   ` Paul E. McKenney
2020-10-06 15:07     ` David Laight [this message]
2020-10-06 21:20 ` Florian Weimer
2020-10-07  9:32   ` Peter Zijlstra
2020-10-07 10:20     ` Florian Weimer
2020-10-07 11:50       ` Peter Zijlstra
2020-10-07 17:11         ` Paul E. McKenney
2020-10-07 21:07           ` Peter Zijlstra
2020-10-07 21:20             ` Paul E. McKenney
2020-10-07 10:30     ` Willy Tarreau

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