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-rw-r--r--docs/devel/rcu.txt34
1 files changed, 17 insertions, 17 deletions
diff --git a/docs/devel/rcu.txt b/docs/devel/rcu.txt
index 0ce15ba198..cdf002edd8 100644
--- a/docs/devel/rcu.txt
+++ b/docs/devel/rcu.txt
@@ -130,13 +130,13 @@ The core RCU API is small:
g_free_rcu(&foo, rcu);
- typeof(*p) atomic_rcu_read(p);
+ typeof(*p) qatomic_rcu_read(p);
- atomic_rcu_read() is similar to atomic_load_acquire(), but it makes
+ qatomic_rcu_read() is similar to qatomic_load_acquire(), but it makes
some assumptions on the code that calls it. This allows a more
optimized implementation.
- atomic_rcu_read assumes that whenever a single RCU critical
+ qatomic_rcu_read assumes that whenever a single RCU critical
section reads multiple shared data, these reads are either
data-dependent or need no ordering. This is almost always the
case when using RCU, because read-side critical sections typically
@@ -144,7 +144,7 @@ The core RCU API is small:
every update) until reaching a data structure of interest,
and then read from there.
- RCU read-side critical sections must use atomic_rcu_read() to
+ RCU read-side critical sections must use qatomic_rcu_read() to
read data, unless concurrent writes are prevented by another
synchronization mechanism.
@@ -152,18 +152,18 @@ The core RCU API is small:
data structure in a single direction, opposite to the direction
in which the updater initializes it.
- void atomic_rcu_set(p, typeof(*p) v);
+ void qatomic_rcu_set(p, typeof(*p) v);
- atomic_rcu_set() is similar to atomic_store_release(), though it also
+ qatomic_rcu_set() is similar to qatomic_store_release(), though it also
makes assumptions on the code that calls it in order to allow a more
optimized implementation.
- In particular, atomic_rcu_set() suffices for synchronization
+ In particular, qatomic_rcu_set() suffices for synchronization
with readers, if the updater never mutates a field within a
data item that is already accessible to readers. This is the
case when initializing a new copy of the RCU-protected data
structure; just ensure that initialization of *p is carried out
- before atomic_rcu_set() makes the data item visible to readers.
+ before qatomic_rcu_set() makes the data item visible to readers.
If this rule is observed, writes will happen in the opposite
order as reads in the RCU read-side critical sections (or if
there is just one update), and there will be no need for other
@@ -212,7 +212,7 @@ DIFFERENCES WITH LINUX
programming; not allowing this would prevent upgrading an RCU read-side
critical section to become an updater.
-- atomic_rcu_read and atomic_rcu_set replace rcu_dereference and
+- qatomic_rcu_read and qatomic_rcu_set replace rcu_dereference and
rcu_assign_pointer. They take a _pointer_ to the variable being accessed.
- call_rcu is a macro that has an extra argument (the name of the first
@@ -257,7 +257,7 @@ may be used as a restricted reference-counting mechanism. For example,
consider the following code fragment:
rcu_read_lock();
- p = atomic_rcu_read(&foo);
+ p = qatomic_rcu_read(&foo);
/* do something with p. */
rcu_read_unlock();
@@ -268,7 +268,7 @@ The write side looks simply like this (with appropriate locking):
qemu_mutex_lock(&foo_mutex);
old = foo;
- atomic_rcu_set(&foo, new);
+ qatomic_rcu_set(&foo, new);
qemu_mutex_unlock(&foo_mutex);
synchronize_rcu();
free(old);
@@ -277,7 +277,7 @@ If the processing cannot be done purely within the critical section, it
is possible to combine this idiom with a "real" reference count:
rcu_read_lock();
- p = atomic_rcu_read(&foo);
+ p = qatomic_rcu_read(&foo);
foo_ref(p);
rcu_read_unlock();
/* do something with p. */
@@ -287,7 +287,7 @@ The write side can be like this:
qemu_mutex_lock(&foo_mutex);
old = foo;
- atomic_rcu_set(&foo, new);
+ qatomic_rcu_set(&foo, new);
qemu_mutex_unlock(&foo_mutex);
synchronize_rcu();
foo_unref(old);
@@ -296,7 +296,7 @@ or with call_rcu:
qemu_mutex_lock(&foo_mutex);
old = foo;
- atomic_rcu_set(&foo, new);
+ qatomic_rcu_set(&foo, new);
qemu_mutex_unlock(&foo_mutex);
call_rcu(foo_unref, old, rcu);
@@ -307,7 +307,7 @@ last reference may be dropped on the read side. Hence you can
use call_rcu() instead:
foo_unref(struct foo *p) {
- if (atomic_fetch_dec(&p->refcount) == 1) {
+ if (qatomic_fetch_dec(&p->refcount) == 1) {
call_rcu(foo_destroy, p, rcu);
}
}
@@ -375,7 +375,7 @@ Instead, we store the size of the array with the array itself:
read side:
rcu_read_lock();
- struct arr *array = atomic_rcu_read(&global_array);
+ struct arr *array = qatomic_rcu_read(&global_array);
x = i < array->size ? array->data[i] : -1;
rcu_read_unlock();
return x;
@@ -392,7 +392,7 @@ Instead, we store the size of the array with the array itself:
/* Removal phase. */
old_array = global_array;
- atomic_rcu_set(&new_array->data, new_array);
+ qatomic_rcu_set(&new_array->data, new_array);
synchronize_rcu();
/* Reclamation phase. */