cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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RCU+sync+read.litmus (704B)

      1C RCU+sync+read
      2
      3(*
      4 * Result: Never
      5 *
      6 * This litmus test demonstrates that after a grace period, an RCU updater always
      7 * sees all stores done in prior RCU read-side critical sections. Such
      8 * read-side critical sections would have ended before the grace period ended.
      9 *
     10 * This is one implication of the RCU grace-period guarantee, which says (among
     11 * other things) that an RCU read-side critical section cannot span a grace period.
     12 *)
     13
     14{
     15int x = 0;
     16int y = 0;
     17}
     18
     19P0(int *x, int *y)
     20{
     21	rcu_read_lock();
     22	WRITE_ONCE(*x, 1);
     23	WRITE_ONCE(*y, 1);
     24	rcu_read_unlock();
     25}
     26
     27P1(int *x, int *y)
     28{
     29	int r0;
     30	int r1;
     31
     32	r0 = READ_ONCE(*x);
     33	synchronize_rcu();
     34	r1 = READ_ONCE(*y);
     35}
     36
     37exists (1:r0=1 /\ 1:r1=0)