From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- tools/memory-model/litmus-tests/MP+polocks.litmus | 35 +++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 tools/memory-model/litmus-tests/MP+polocks.litmus (limited to 'tools/memory-model/litmus-tests/MP+polocks.litmus') diff --git a/tools/memory-model/litmus-tests/MP+polocks.litmus b/tools/memory-model/litmus-tests/MP+polocks.litmus new file mode 100644 index 000000000..712a4fcdf --- /dev/null +++ b/tools/memory-model/litmus-tests/MP+polocks.litmus @@ -0,0 +1,35 @@ +C MP+polocks + +(* + * Result: Never + * + * This litmus test demonstrates how lock acquisitions and releases can + * stand in for smp_load_acquire() and smp_store_release(), respectively. + * In other words, when holding a given lock (or indeed after releasing a + * given lock), a CPU is not only guaranteed to see the accesses that other + * CPUs made while previously holding that lock, it is also guaranteed + * to see all prior accesses by those other CPUs. + *) + +{} + +P0(int *x, int *y, spinlock_t *mylock) +{ + WRITE_ONCE(*x, 1); + spin_lock(mylock); + WRITE_ONCE(*y, 1); + spin_unlock(mylock); +} + +P1(int *x, int *y, spinlock_t *mylock) +{ + int r0; + int r1; + + spin_lock(mylock); + r0 = READ_ONCE(*y); + spin_unlock(mylock); + r1 = READ_ONCE(*x); +} + +exists (1:r0=1 /\ 1:r1=0) -- cgit v1.2.3