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authorTakashi Iwai <tiwai@suse.de>2020-09-02 13:31:45 +0200
committerTakashi Iwai <tiwai@suse.de>2020-09-02 13:32:06 +0200
commit6bde8ef51c917a657476310728d6cb3de6bac9e4 (patch)
treeba8a63abee1fa74d849dc9fc59e0854bc99a8524 /Documentation/litmus-tests/rcu/RCU+sync+read.litmus
parent949a1ebe8cea7b342085cb6a4946b498306b9493 (diff)
parent07da90b0e5fc299c0ce4d34d1916d7a79b86848b (diff)
Merge branch 'topic/tasklet-convert' into for-linus
Pull tasklet API conversions. Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'Documentation/litmus-tests/rcu/RCU+sync+read.litmus')
-rw-r--r--Documentation/litmus-tests/rcu/RCU+sync+read.litmus37
1 files changed, 37 insertions, 0 deletions
diff --git a/Documentation/litmus-tests/rcu/RCU+sync+read.litmus b/Documentation/litmus-tests/rcu/RCU+sync+read.litmus
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index 000000000000..f34176720231
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+++ b/Documentation/litmus-tests/rcu/RCU+sync+read.litmus
@@ -0,0 +1,37 @@
+C RCU+sync+read
+
+(*
+ * Result: Never
+ *
+ * This litmus test demonstrates that after a grace period, an RCU updater always
+ * sees all stores done in prior RCU read-side critical sections. Such
+ * read-side critical sections would have ended before the grace period ended.
+ *
+ * This is one implication of the RCU grace-period guarantee, which says (among
+ * other things) that an RCU read-side critical section cannot span a grace period.
+ *)
+
+{
+int x = 0;
+int y = 0;
+}
+
+P0(int *x, int *y)
+{
+ rcu_read_lock();
+ WRITE_ONCE(*x, 1);
+ WRITE_ONCE(*y, 1);
+ rcu_read_unlock();
+}
+
+P1(int *x, int *y)
+{
+ int r0;
+ int r1;
+
+ r0 = READ_ONCE(*x);
+ synchronize_rcu();
+ r1 = READ_ONCE(*y);
+}
+
+exists (1:r0=1 /\ 1:r1=0)