[PATCH 1/3] tools: memory-model: Prepare for data-race detection
From: Alan Stern
Date: Mon Apr 22 2019 - 12:17:48 EST
This patch makes some slight alterations to linux-kernel.cat in
preparation for adding support for data-race detection to the
Linux-Kernel Memory Model.
The definitions of relations involved in Acquire, Release, and
unlock-lock ordering are moved up earlier in the source file.
The rmb relation is factored through the new R4rmb class: the
class of reads to which rmb will apply.
The definition of the fence relation is moved earlier, and it
is split up into read- and write-fences (rmb and wmb) and all
This should not make any functional changes.
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
tools/memory-model/linux-kernel.cat | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
@@ -26,8 +26,14 @@ include "lock.cat"
(* Basic relations *)
+(* Release Acquire *)
+let acq-po = [Acquire] ; po ; [M]
+let po-rel = [M] ; po ; [Release]
+let po-unlock-rf-lock-po = po ; [UL] ; rf ; [LKR] ; po
(* Fences *)
-let rmb = [R \ Noreturn] ; fencerel(Rmb) ; [R \ Noreturn]
+let R4rmb = R \ Noreturn (* Reads for which rmb works *)
+let rmb = [R4rmb] ; fencerel(Rmb) ; [R4rmb]
let wmb = [W] ; fencerel(Wmb) ; [W]
let mb = ([M] ; fencerel(Mb) ; [M]) |
([M] ; fencerel(Before-atomic) ; [RMW] ; po? ; [M]) |
@@ -36,13 +42,10 @@ let mb = ([M] ; fencerel(Mb) ; [M]) |
([M] ; po ; [UL] ; (co | po) ; [LKW] ;
fencerel(After-unlock-lock) ; [M])
let gp = po ; [Sync-rcu | Sync-srcu] ; po?
let strong-fence = mb | gp
-(* Release Acquire *)
-let acq-po = [Acquire] ; po ; [M]
-let po-rel = [M] ; po ; [Release]
-let po-unlock-rf-lock-po = po ; [UL] ; rf ; [LKR] ; po
+let nonrw-fence = strong-fence | po-rel | acq-po
+let fence = nonrw-fence | wmb | rmb
(* Fundamental coherence ordering *)
@@ -65,7 +68,6 @@ let rwdep = (dep | ctrl) ; [W]
let overwrite = co | fr
let to-w = rwdep | (overwrite & int)
let to-r = addr | (dep ; rfi)
-let fence = strong-fence | wmb | po-rel | rmb | acq-po
let ppo = to-r | to-w | fence | (po-unlock-rf-lock-po & int)
(* Propagation: Ordering from release operations and strong fences. *)