tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus

Source file repositories/reference/linux-study-clean/tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus

File Facts

System
Linux kernel
Corpus path
tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus
Extension
.litmus
Size
745 bytes
Lines
35
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: tools
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

C MP+polockmbonce+poacquiresilsil

(*
 * Result: Never
 *
 * Do spinlocks combined with smp_mb__after_spinlock() provide order
 * to outside observers using spin_is_locked() to sense the lock-held
 * state, ordered by acquire?  Note that when the first spin_is_locked()
 * returns false and the second true, we know that the smp_load_acquire()
 * executed before the lock was acquired (loosely speaking).
 *)

{}

P0(spinlock_t *lo, int *x) // Producer
{
	spin_lock(lo);
	smp_mb__after_spinlock();
	WRITE_ONCE(*x, 1);
	spin_unlock(lo);
}

P1(spinlock_t *lo, int *x) // Consumer
{
	int r1;
	int r2;
	int r3;

	r1 = smp_load_acquire(x);
	r2 = spin_is_locked(lo);
	r3 = spin_is_locked(lo);
}

exists (1:r1=1 /\ 1:r2=0 /\ 1:r3=1) (* Bad outcome. *)

Annotation

Implementation Notes