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Mark Rutland
af41db5ef7
Since commit:
b899a85043 ("compiler.h: Remove ACCESS_ONCE()")
... there has been no definition of ACCESS_ONCE() in the kernel tree,
and it has been necessary to use READ_ONCE() or WRITE_ONCE() instead.
Correspondingly, let's remove ACCESS_ONCE() from the kernel memory
model.
Signed-off-by: Mark Rutland <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Acked-by: Andrea Parri <[email protected]>
Cc: Akira Yokosawa <[email protected]>
Cc: Alan Stern <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: David Howells <[email protected]>
Cc: Jade Alglave <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Luc Maranget <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
53 lines
1.9 KiB
Plaintext
53 lines
1.9 KiB
Plaintext
// SPDX-License-Identifier: GPL-2.0+
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(*
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* Copyright (C) 2015 Jade Alglave <[email protected]>,
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* Copyright (C) 2016 Luc Maranget <[email protected]> for Inria
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* Copyright (C) 2017 Alan Stern <[email protected]>,
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* Andrea Parri <[email protected]>
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*
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* An earlier version of this file appeared in the companion webpage for
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* "Frightening small children and disconcerting grown-ups: Concurrency
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* in the Linux kernel" by Alglave, Maranget, McKenney, Parri, and Stern,
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* which appeared in ASPLOS 2018.
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*)
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"Linux-kernel memory consistency model"
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enum Accesses = 'once (*READ_ONCE,WRITE_ONCE*) ||
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'release (*smp_store_release*) ||
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'acquire (*smp_load_acquire*) ||
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'noreturn (* R of non-return RMW *)
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instructions R[{'once,'acquire,'noreturn}]
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instructions W[{'once,'release}]
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instructions RMW[{'once,'acquire,'release}]
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enum Barriers = 'wmb (*smp_wmb*) ||
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'rmb (*smp_rmb*) ||
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'mb (*smp_mb*) ||
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'rcu-lock (*rcu_read_lock*) ||
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'rcu-unlock (*rcu_read_unlock*) ||
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'sync-rcu (*synchronize_rcu*) ||
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'before-atomic (*smp_mb__before_atomic*) ||
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'after-atomic (*smp_mb__after_atomic*) ||
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'after-spinlock (*smp_mb__after_spinlock*)
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instructions F[Barriers]
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(* Compute matching pairs of nested Rcu-lock and Rcu-unlock *)
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let matched = let rec
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unmatched-locks = Rcu-lock \ domain(matched)
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and unmatched-unlocks = Rcu-unlock \ range(matched)
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and unmatched = unmatched-locks | unmatched-unlocks
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and unmatched-po = [unmatched] ; po ; [unmatched]
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and unmatched-locks-to-unlocks =
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[unmatched-locks] ; po ; [unmatched-unlocks]
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and matched = matched | (unmatched-locks-to-unlocks \
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(unmatched-po ; unmatched-po))
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in matched
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(* Validate nesting *)
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flag ~empty Rcu-lock \ domain(matched) as unbalanced-rcu-locking
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flag ~empty Rcu-unlock \ range(matched) as unbalanced-rcu-locking
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(* Outermost level of nesting only *)
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let crit = matched \ (po^-1 ; matched ; po^-1)
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