mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
30 lines
545 B
30 lines
545 B
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. *)
|
|
|