Re: [PATCH v2 2/2] tools/memory-model: Make ppo a subrelation of po

Andrea Parri
2023-01-29T17:28:36Z

> Why can't P3's spin_lock() read from that initial write?

Mmh, sounds like you want to play with something like below?

Andrea

diff --git a/tools/memory-model/lock.cat b/tools/memory-model/lock.cat
index 6b52f365d73ac..20c3af4511255 100644
--- a/tools/memory-model/lock.cat
+++ b/tools/memory-model/lock.cat
@@ -74,7 +74,6 @@ flag ~empty UL \ range(critical) as unmatched-unlock

(* Allow up to one unmatched LKW per location; more must deadlock *)
let UNMATCHED-LKW = LKW \ domain(critical)
-empty ([UNMATCHED-LKW] ; loc ; [UNMATCHED-LKW]) \ id as unmatched-locks

(* rfi for LF events: link each LKW to the LF events in its critical section *)
let rfi-lf = ([LKW] ; po-loc ; [LF]) \ ([LKW] ; po-loc ; [UL] ; po-loc)
@@ -120,8 +119,7 @@ let rf-ru = rfe-ru | rfi-ru
let rf = rf | rf-lf | rf-ru

(* Generate all co relations, including LKW events but not UL *)
-let co0 = co0 | ([IW] ; loc ; [LKW]) |
- (([LKW] ; loc ; [UNMATCHED-LKW]) \ [UNMATCHED-LKW])
+let co0 = co0 | ([IW] ; loc ; [LKW])
include "cos-opt.cat"
let W = W | UL
let M = R | W