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Diffstat (limited to 'tools/memory-model/lock.cat')
-rw-r--r-- | tools/memory-model/lock.cat | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/tools/memory-model/lock.cat b/tools/memory-model/lock.cat new file mode 100644 index 000000000000..ba4a4ec6d313 --- /dev/null +++ b/tools/memory-model/lock.cat @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0+ +(* + * Copyright (C) 2016 Luc Maranget <luc.maranget@inria.fr> for Inria + * Copyright (C) 2017 Alan Stern <stern@rowland.harvard.edu> + *) + +(* Generate coherence orders and handle lock operations *) + +include "cross.cat" + +(* From lock reads to their partner lock writes *) +let lk-rmw = ([LKR] ; po-loc ; [LKW]) \ (po ; po) +let rmw = rmw | lk-rmw + +(* + * A paired 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 + +(* There should be no R or W accesses to spinlocks *) +let ALL-LOCKS = LKR | LKW | UL | LF +flag ~empty [M \ IW] ; loc ; [ALL-LOCKS] as mixed-lock-accesses + +(* The final value of a spinlock should not be tested *) +flag ~empty [FW] ; loc ; [ALL-LOCKS] as lock-final + + +(* + * Put lock operations in their appropriate classes, but leave UL out of W + * until after the co relation has been generated. + *) +let R = R | LKR | LF +let W = W | LKW + +let Release = Release | UL +let Acquire = Acquire | LKR + + +(* Match LKW events to their corresponding UL events *) +let critical = ([LKW] ; po-loc ; [UL]) \ (po-loc ; [LKW | UL] ; po-loc) + +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) + +(* rfe for LF events *) +let all-possible-rfe-lf = + (* + * Given an LF event r, compute the possible rfe edges for that event + * (all those starting from LKW events in other threads), + * and then convert that relation to a set of single-edge relations. + *) + let possible-rfe-lf r = + let pair-to-relation p = p ++ 0 + in map pair-to-relation ((LKW * {r}) & loc & ext) + (* Do this for each LF event r that isn't in rfi-lf *) + in map possible-rfe-lf (LF \ range(rfi-lf)) + +(* Generate all rf relations for LF events *) +with rfe-lf from cross(all-possible-rfe-lf) +let rf = rf | rfi-lf | rfe-lf + + +(* Generate all co relations, including LKW events but not UL *) +let co0 = co0 | ([IW] ; loc ; [LKW]) | + (([LKW] ; loc ; [UNMATCHED-LKW]) \ [UNMATCHED-LKW]) +include "cos-opt.cat" +let W = W | UL +let M = R | W + +(* Merge UL events into co *) +let co = (co | critical | (critical^-1 ; co))+ +let coe = co & ext +let coi = co & int + +(* Merge LKR events into rf *) +let rf = rf | ([IW | UL] ; singlestep(co) ; lk-rmw^-1) +let rfe = rf & ext +let rfi = rf & int + +let fr = rf^-1 ; co +let fre = fr & ext +let fri = fr & int + +show co,rf,fr |