[Patch 1/2] tools/memory-model: Update some warning labels

From: Alan Stern
Date: Wed Jan 25 2023 - 15:20:55 EST


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@xxxxxxxxxxxxxxxxxxx>

---

tools/memory-model/linux-kernel.bell | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

Index: usb-devel/tools/memory-model/linux-kernel.bell
===================================================================
--- usb-devel.orig/tools/memory-model/linux-kernel.bell
+++ usb-devel/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) |