Messages in this thread Patch in this message | | | Date | Mon, 14 May 2018 23:34:19 -0700 | From | tip-bot for Alan Stern <> | Subject | [tip:locking/core] tools/memory-model: Remove out-of-date comments and code from lock.cat |
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Commit-ID: cee0321a404fe6b43d1f4364639c8ffe2f2b37d1 Gitweb: https://git.kernel.org/tip/cee0321a404fe6b43d1f4364639c8ffe2f2b37d1 Author: Alan Stern <stern@rowland.harvard.edu> AuthorDate: Mon, 14 May 2018 16:33:53 -0700 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Tue, 15 May 2018 08:11:18 +0200
tools/memory-model: Remove out-of-date comments and code from lock.cat
lock.cat contains old comments and code referring to the possibility of LKR events that are not part of an RMW pair. This is a holdover from when I though we might end up using LKR events to implement spin_is_locked(). Reword the comments to remove this assumption and replace domain(lk-rmw) in the code with LKR.
Tested-by: Andrea Parri <andrea.parri@amarulasolutions.com> [ paulmck: Pulled as lock-nest into previous line as discussed. ] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Akira Yokosawa <akiyks@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: Jade Alglave <j.alglave@ucl.ac.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luc Maranget <luc.maranget@inria.fr> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Cc: parri.andrea@gmail.com Link: http://lkml.kernel.org/r/1526340837-12222-15-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- tools/memory-model/lock.cat | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/tools/memory-model/lock.cat b/tools/memory-model/lock.cat index 7217cd4941a4..cd002a33ca8a 100644 --- a/tools/memory-model/lock.cat +++ b/tools/memory-model/lock.cat @@ -47,18 +47,15 @@ flag ~empty [M \ IW] ; loc ; [ALL-LOCKS] as mixed-lock-accesses let lk-rmw = ([LKR] ; po-loc ; [LKW]) \ (po ; po) let rmw = rmw | lk-rmw +(* The litmus test is invalid if an LKR/LKW event is not part of an RMW pair *) +flag ~empty LKW \ range(lk-rmw) as unpaired-LKW +flag ~empty LKR \ domain(lk-rmw) as unpaired-LKR + (* - * A paired LKR must always see an unlocked value; spin_lock() calls nested + * An LKR must always see an unlocked value; spin_lock() calls nested * inside a critical section (for the same lock) always deadlock. *) -empty ([LKW] ; po-loc ; [domain(lk-rmw)]) \ (po-loc ; [UL] ; po-loc) - as lock-nest - -(* The litmus test is invalid if an LKW event is not part of an RMW pair *) -flag ~empty LKW \ range(lk-rmw) as unpaired-LKW - -(* This will be allowed if we implement spin_is_locked() *) -flag ~empty LKR \ domain(lk-rmw) as unpaired-LKR +empty ([LKW] ; po-loc ; [LKR]) \ (po-loc ; [UL] ; po-loc) as lock-nest (* The final value of a spinlock should not be tested *) flag ~empty [FW] ; loc ; [ALL-LOCKS] as lock-final
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