Signed-off-by: Junchang Wang <junchangwang@xxxxxxxxx>
---
CodeSamples/defer/rcu_rcpls.c | 6 +++---
CodeSamples/defer/rcu_rcpls.h | 2 +-
CodeSamples/defer/rcutorture.h | 2 +-
appendix/toyrcu/toyrcu.tex | 14 +++++++-------
4 files changed, 12 insertions(+), 12 deletions(-)
diff --git a/CodeSamples/defer/rcu_rcpls.c b/CodeSamples/defer/rcu_rcpls.c
index 8dbf624..3018ae9 100644
--- a/CodeSamples/defer/rcu_rcpls.c
+++ b/CodeSamples/defer/rcu_rcpls.c
@@ -28,7 +28,7 @@ static void flip_counter_and_wait(int ctr)
int i;
int t;
- ACCESS_ONCE(rcu_idx) = ctr + 1;
+ WRITE_ONCE(rcu_idx, ctr + 1);
i = ctr & 0x1;
smp_mb();
for_each_thread(t) {
@@ -46,10 +46,10 @@ void synchronize_rcu(void)
int oldctr;
smp_mb();
- oldctr = ACCESS_ONCE(rcu_idx);
+ oldctr = READ_ONCE(rcu_idx);
smp_mb();
spin_lock(&rcu_gp_lock);
- ctr = ACCESS_ONCE(rcu_idx);
+ ctr = READ_ONCE(rcu_idx);
if (ctr - oldctr >= 3) {
/*
diff --git a/CodeSamples/defer/rcu_rcpls.h b/CodeSamples/defer/rcu_rcpls.h
index a9c7723..6825270 100644
--- a/CodeSamples/defer/rcu_rcpls.h
+++ b/CodeSamples/defer/rcu_rcpls.h
@@ -47,7 +47,7 @@ static void rcu_read_lock(void)
n = __get_thread_var(rcu_nesting);
if (n == 0) {
- i = ACCESS_ONCE(rcu_idx) & 0x1;
+ i = READ_ONCE(rcu_idx) & 0x1;
__get_thread_var(rcu_read_idx) = i;
__get_thread_var(rcu_refcnt)[i]++;
}
diff --git a/CodeSamples/defer/rcutorture.h b/CodeSamples/defer/rcutorture.h
index c5bc87e..ca03df9 100644
--- a/CodeSamples/defer/rcutorture.h
+++ b/CodeSamples/defer/rcutorture.h
@@ -271,7 +271,7 @@ void *rcu_read_stress_test(void *arg)
n_mberror++;
rcu_read_lock_nest();
for (i = 0; i < 100; i++)
- ACCESS_ONCE(garbage)++;
+ WRITE_ONCE(garbage, READ_ONCE(garbage) + 1);
rcu_read_unlock_nest();
pc = p->pipe_count;
rcu_read_unlock();
diff --git a/appendix/toyrcu/toyrcu.tex b/appendix/toyrcu/toyrcu.tex
index b4882c3..5e74afa 100644
--- a/appendix/toyrcu/toyrcu.tex
+++ b/appendix/toyrcu/toyrcu.tex
@@ -1003,7 +1003,7 @@ concurrent RCU updates.
5
6 n = __get_thread_var(rcu_nesting);
7 if (n == 0) {
- 8 i = ACCESS_ONCE(rcu_idx) & 0x1;
+ 8 i = READ_ONCE(rcu_idx) & 0x1;
9 __get_thread_var(rcu_read_idx) = i;
10 __get_thread_var(rcu_refcnt)[i]++;
11 }
@@ -1044,7 +1044,7 @@ so that line~8 of
Figure~\ref{fig:app:toyrcu:RCU Read-Side Using Per-Thread Reference-Count Pair and Shared Update}
must mask off the low-order bit.
We also switched from using \co{atomic_read()} and \co{atomic_set()}
-to using \co{ACCESS_ONCE()}.
+to using \co{READ_ONCE()}.
The data is also quite similar, as shown in
Figure~\ref{fig:app:toyrcu:RCU Read-Side Using Per-Thread Reference-Count Pair and Shared Update Data},
with \co{rcu_idx} now being a \co{long} instead of an
@@ -1058,7 +1058,7 @@ with \co{rcu_idx} now being a \co{long} instead of an
3 int i;
4 int t;
5
- 6 ACCESS_ONCE(rcu_idx) = ctr + 1;
+ 6 WRITE_ONCE(rcu_idx, ctr + 1);
7 i = ctr & 0x1;
8 smp_mb();
9 for_each_thread(t) {
@@ -1075,10 +1075,10 @@ with \co{rcu_idx} now being a \co{long} instead of an
20 int oldctr;
21
22 smp_mb();
- 23 oldctr = ACCESS_ONCE(rcu_idx);
+ 23 oldctr = READ_ONCE(rcu_idx);
24 smp_mb();
25 spin_lock(&rcu_gp_lock);
- 26 ctr = ACCESS_ONCE(rcu_idx);
+ 26 ctr = READ_ONCE(rcu_idx);
27 if (ctr - oldctr >= 3) {
28 spin_unlock(&rcu_gp_lock);
29 smp_mb();
@@ -1106,7 +1106,7 @@ These are similar to those in
Figure~\ref{fig:app:toyrcu:RCU Update Using Per-Thread Reference-Count Pair}.
The differences in \co{flip_counter_and_wait()} include:
\begin{enumerate}
-\item Line~6 uses \co{ACCESS_ONCE()} instead of \co{atomic_set()},
+\item Line~6 uses \co{WRITE_ONCE()} instead of \co{atomic_set()},
and increments rather than complementing.
\item A new line~7 masks the counter down to its bottom bit.
\end{enumerate}
@@ -1116,7 +1116,7 @@ The changes to \co{synchronize_rcu()} are more pervasive:
\item There is a new \co{oldctr} local variable that captures
the pre-lock-acquisition value of \co{rcu_idx} on
line~23.
-\item Line~26 uses \co{ACCESS_ONCE()} instead of \co{atomic_read()}.
+\item Line~26 uses \co{READ_ONCE()} instead of \co{atomic_read()}.
\item Lines~27-30 check to see if at least three counter flips were
performed by other threads while the lock was being acquired,
and, if so, releases the lock, does a memory barrier, and returns.
--
2.7.4
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