tools/memory-model/litmus-tests/Z6.0+pooncelock+poonceLock+pombonce.litmus

Source file repositories/reference/linux-study-clean/tools/memory-model/litmus-tests/Z6.0+pooncelock+poonceLock+pombonce.litmus

File Facts

System
Linux kernel
Corpus path
tools/memory-model/litmus-tests/Z6.0+pooncelock+poonceLock+pombonce.litmus
Extension
.litmus
Size
723 bytes
Lines
43
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 Z6.0+pooncelock+poonceLock+pombonce

(*
 * Result: Never
 *
 * This litmus test demonstrates how smp_mb__after_spinlock() may be
 * used to ensure that accesses in different critical sections for a
 * given lock running on different CPUs are nevertheless seen in order
 * by CPUs not holding that lock.
 *)

{}

P0(int *x, int *y, spinlock_t *mylock)
{
	spin_lock(mylock);
	WRITE_ONCE(*x, 1);
	WRITE_ONCE(*y, 1);
	spin_unlock(mylock);
}

P1(int *y, int *z, spinlock_t *mylock)
{
	int r0;

	spin_lock(mylock);
	smp_mb__after_spinlock();
	r0 = READ_ONCE(*y);
	WRITE_ONCE(*z, 1);
	spin_unlock(mylock);
}

P2(int *x, int *z)
{
	int r1;

	WRITE_ONCE(*z, 2);
	smp_mb();
	r1 = READ_ONCE(*x);
}

exists (1:r0=1 /\ z=2 /\ 2:r1=0)

Annotation

Implementation Notes