From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- .../MP+fencewmbonceonce+fencermbonceonce.litmus | 30 ++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus (limited to 'tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus') diff --git a/tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus b/tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus new file mode 100644 index 000000000..f8ca12298 --- /dev/null +++ b/tools/memory-model/litmus-tests/MP+fencewmbonceonce+fencermbonceonce.litmus @@ -0,0 +1,30 @@ +C MP+fencewmbonceonce+fencermbonceonce + +(* + * Result: Never + * + * This litmus test demonstrates that smp_wmb() and smp_rmb() provide + * sufficient ordering for the message-passing pattern. However, it + * is usually better to use smp_store_release() and smp_load_acquire(). + *) + +{} + +P0(int *buf, int *flag) // Producer +{ + WRITE_ONCE(*buf, 1); + smp_wmb(); + WRITE_ONCE(*flag, 1); +} + +P1(int *buf, int *flag) // Consumer +{ + int r0; + int r1; + + r0 = READ_ONCE(*flag); + smp_rmb(); + r1 = READ_ONCE(*buf); +} + +exists (1:r0=1 /\ 1:r1=0) (* Bad outcome. *) -- cgit v1.2.3