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Date:   Wed, 22 Mar 2023 01:51:22 +0100
From:   Andrea Parri <parri.andrea@gmail.com>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        kernel-team@meta.com, mingo@kernel.org, stern@rowland.harvard.edu,
        will@kernel.org, peterz@infradead.org, boqun.feng@gmail.com,
        npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk,
        luc.maranget@inria.fr, akiyks@gmail.com,
        Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>
Subject: Re: [PATCH memory-model 1/8] tools/memory-model: Update some warning
 labels
Message-ID: <ZBpRCiHuC6LPkFOc@andrea>
References: <778147e4-ccab-40cf-b6ef-31abe4e3f6b7@paulmck-laptop>
 <20230321010246.50960-1-paulmck@kernel.org>
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On Mon, Mar 20, 2023 at 06:02:39PM -0700, Paul E. McKenney wrote:
> From: Alan Stern <stern@rowland.harvard.edu>
> 
> Some of the warning labels used in the LKMM are unfortunately
> ambiguous.  In particular, the same warning is used for both an
> unmatched rcu_read_lock() call and for an unmatched rcu_read_unlock()
> call.  Likewise for the srcu_* equivalents.  Also, the warning about
> passing a wrong value to srcu_read_unlock() -- i.e., a value different
> from the one returned by the matching srcu_read_lock() -- talks about
> bad nesting rather than non-matching values.
> 
> Let's update the warning labels to make their meanings more clear.
> 
> Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
> Reviewed-by: Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>
> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Acked-by: Andrea Parri <parri.andrea@gmail.com>

  Andrea


> ---
>  tools/memory-model/linux-kernel.bell | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/memory-model/linux-kernel.bell b/tools/memory-model/linux-kernel.bell
> index 70a9073dec3e..dc464854d28a 100644
> --- a/tools/memory-model/linux-kernel.bell
> +++ b/tools/memory-model/linux-kernel.bell
> @@ -53,8 +53,8 @@ let rcu-rscs = let rec
>  	in matched
>  
>  (* Validate nesting *)
> -flag ~empty Rcu-lock \ domain(rcu-rscs) as unbalanced-rcu-locking
> -flag ~empty Rcu-unlock \ range(rcu-rscs) as unbalanced-rcu-locking
> +flag ~empty Rcu-lock \ domain(rcu-rscs) as unmatched-rcu-lock
> +flag ~empty Rcu-unlock \ range(rcu-rscs) as unmatched-rcu-unlock
>  
>  (* Compute matching pairs of nested Srcu-lock and Srcu-unlock *)
>  let srcu-rscs = let rec
> @@ -69,14 +69,14 @@ let srcu-rscs = let rec
>  	in matched
>  
>  (* Validate nesting *)
> -flag ~empty Srcu-lock \ domain(srcu-rscs) as unbalanced-srcu-locking
> -flag ~empty Srcu-unlock \ range(srcu-rscs) as unbalanced-srcu-locking
> +flag ~empty Srcu-lock \ domain(srcu-rscs) as unmatched-srcu-lock
> +flag ~empty Srcu-unlock \ range(srcu-rscs) as unmatched-srcu-unlock
>  
>  (* Check for use of synchronize_srcu() inside an RCU critical section *)
>  flag ~empty rcu-rscs & (po ; [Sync-srcu] ; po) as invalid-sleep
>  
>  (* Validate SRCU dynamic match *)
> -flag ~empty different-values(srcu-rscs) as srcu-bad-nesting
> +flag ~empty different-values(srcu-rscs) as srcu-bad-value-match
>  
>  (* Compute marked and plain memory accesses *)
>  let Marked = (~M) | IW | Once | Release | Acquire | domain(rmw) | range(rmw) |
> -- 
> 2.40.0.rc2
>