aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/RCU/whatisRCU.rst
diff options
context:
space:
mode:
authorIngo Molnar <mingo@kernel.org>2021-02-12 12:50:09 +0100
committerIngo Molnar <mingo@kernel.org>2021-02-12 12:56:55 +0100
commit85e853c5ec8486117182baab10c98b321daa6d47 (patch)
tree404551f51bc88ba9f4cc64431e2633493a971842 /Documentation/RCU/whatisRCU.rst
parentMerge tag 'powerpc-5.11-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux (diff)
parentMerge branches 'doc.2021.01.06a', 'fixes.2021.01.04b', 'kfree_rcu.2021.01.04a', 'mmdumpobj.2021.01.22a', 'nocb.2021.01.06a', 'rt.2021.01.04a', 'stall.2021.01.06a', 'torture.2021.01.12a' and 'tortureall.2021.01.06a' into HEAD (diff)
downloadlinux-dev-85e853c5ec8486117182baab10c98b321daa6d47.tar.xz
linux-dev-85e853c5ec8486117182baab10c98b321daa6d47.zip
Merge branch 'for-mingo-rcu' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney: - Documentation updates. - Miscellaneous fixes. - kfree_rcu() updates: Addition of mem_dump_obj() to provide allocator return addresses to more easily locate bugs. This has a couple of RCU-related commits, but is mostly MM. Was pulled in with akpm's agreement. - Per-callback-batch tracking of numbers of callbacks, which enables better debugging information and smarter reactions to large numbers of callbacks. - The first round of changes to allow CPUs to be runtime switched from and to callback-offloaded state. - CONFIG_PREEMPT_RT-related changes. - RCU CPU stall warning updates. - Addition of polling grace-period APIs for SRCU. - Torture-test and torture-test scripting updates, including a "torture everything" script that runs rcutorture, locktorture, scftorture, rcuscale, and refscale. Plus does an allmodconfig build. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'Documentation/RCU/whatisRCU.rst')
-rw-r--r--Documentation/RCU/whatisRCU.rst10
1 files changed, 5 insertions, 5 deletions
diff --git a/Documentation/RCU/whatisRCU.rst b/Documentation/RCU/whatisRCU.rst
index 1a4723f48bd9..17e95ab2a201 100644
--- a/Documentation/RCU/whatisRCU.rst
+++ b/Documentation/RCU/whatisRCU.rst
@@ -683,7 +683,7 @@ Quick Quiz #1:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This section presents a "toy" RCU implementation that is based on
"classic RCU". It is also short on performance (but only for updates) and
-on features such as hotplug CPU and the ability to run in CONFIG_PREEMPT
+on features such as hotplug CPU and the ability to run in CONFIG_PREEMPTION
kernels. The definitions of rcu_dereference() and rcu_assign_pointer()
are the same as those shown in the preceding section, so they are omitted.
::
@@ -739,7 +739,7 @@ Quick Quiz #2:
Quick Quiz #3:
If it is illegal to block in an RCU read-side
critical section, what the heck do you do in
- PREEMPT_RT, where normal spinlocks can block???
+ CONFIG_PREEMPT_RT, where normal spinlocks can block???
:ref:`Answers to Quick Quiz <8_whatisRCU>`
@@ -1093,7 +1093,7 @@ Quick Quiz #2:
overhead is **negative**.
Answer:
- Imagine a single-CPU system with a non-CONFIG_PREEMPT
+ Imagine a single-CPU system with a non-CONFIG_PREEMPTION
kernel where a routing table is used by process-context
code, but can be updated by irq-context code (for example,
by an "ICMP REDIRECT" packet). The usual way of handling
@@ -1120,10 +1120,10 @@ Answer:
Quick Quiz #3:
If it is illegal to block in an RCU read-side
critical section, what the heck do you do in
- PREEMPT_RT, where normal spinlocks can block???
+ CONFIG_PREEMPT_RT, where normal spinlocks can block???
Answer:
- Just as PREEMPT_RT permits preemption of spinlock
+ Just as CONFIG_PREEMPT_RT permits preemption of spinlock
critical sections, it permits preemption of RCU
read-side critical sections. It also permits
spinlocks blocking while in RCU read-side critical