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-rw-r--r--Documentation/RCU/Design/Requirements/Requirements.html7
1 files changed, 4 insertions, 3 deletions
diff --git a/Documentation/RCU/Design/Requirements/Requirements.html b/Documentation/RCU/Design/Requirements/Requirements.html
index 62e847bcdcdd..49690228b1c6 100644
--- a/Documentation/RCU/Design/Requirements/Requirements.html
+++ b/Documentation/RCU/Design/Requirements/Requirements.html
@@ -581,7 +581,8 @@ This guarantee was only partially premeditated.
DYNIX/ptx used an explicit memory barrier for publication, but had nothing
resembling <tt>rcu_dereference()</tt> for subscription, nor did it
have anything resembling the <tt>smp_read_barrier_depends()</tt>
-that was later subsumed into <tt>rcu_dereference()</tt>.
+that was later subsumed into <tt>rcu_dereference()</tt> and later
+still into <tt>READ_ONCE()</tt>.
The need for these operations made itself known quite suddenly at a
late-1990s meeting with the DEC Alpha architects, back in the days when
DEC was still a free-standing company.
@@ -2797,7 +2798,7 @@ RCU must avoid degrading real-time response for CPU-bound threads, whether
executing in usermode (which is one use case for
<tt>CONFIG_NO_HZ_FULL=y</tt>) or in the kernel.
That said, CPU-bound loops in the kernel must execute
-<tt>cond_resched_rcu_qs()</tt> at least once per few tens of milliseconds
+<tt>cond_resched()</tt> at least once per few tens of milliseconds
in order to avoid receiving an IPI from RCU.
<p>
@@ -3128,7 +3129,7 @@ The solution, in the form of
is to have implicit
read-side critical sections that are delimited by voluntary context
switches, that is, calls to <tt>schedule()</tt>,
-<tt>cond_resched_rcu_qs()</tt>, and
+<tt>cond_resched()</tt>, and
<tt>synchronize_rcu_tasks()</tt>.
In addition, transitions to and from userspace execution also delimit
tasks-RCU read-side critical sections.