From 058cc23bcad08aca62987cc795fe406ac39146d0 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 21 Apr 2020 19:04:04 +0200 Subject: [PATCH] docs: RCU: Convert lockdep.txt to ReST - Add a SPDX header; - Adjust document title; - Mark literal blocks as such; - Add it to RCU/index.rst. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Paul E. McKenney --- Documentation/RCU/index.rst | 1 + Documentation/RCU/{lockdep.txt => lockdep.rst} | 12 ++++++++---- 2 files changed, 9 insertions(+), 4 deletions(-) rename Documentation/RCU/{lockdep.txt => lockdep.rst} (96%) diff --git a/Documentation/RCU/index.rst b/Documentation/RCU/index.rst index 430a37132b2c..fa7a2a8949b7 100644 --- a/Documentation/RCU/index.rst +++ b/Documentation/RCU/index.rst @@ -11,6 +11,7 @@ RCU concepts arrayRCU checklist + lockdep lockdep-splat rcubarrier rcu_dereference diff --git a/Documentation/RCU/lockdep.txt b/Documentation/RCU/lockdep.rst similarity index 96% rename from Documentation/RCU/lockdep.txt rename to Documentation/RCU/lockdep.rst index 89db949eeca0..f1fc8ae3846a 100644 --- a/Documentation/RCU/lockdep.txt +++ b/Documentation/RCU/lockdep.rst @@ -1,4 +1,8 @@ +.. SPDX-License-Identifier: GPL-2.0 + +======================== RCU and lockdep checking +======================== All flavors of RCU have lockdep checking available, so that lockdep is aware of when each task enters and leaves any flavor of RCU read-side @@ -8,7 +12,7 @@ tracking to include RCU state, which can sometimes help when debugging deadlocks and the like. In addition, RCU provides the following primitives that check lockdep's -state: +state:: rcu_read_lock_held() for normal RCU. rcu_read_lock_bh_held() for RCU-bh. @@ -63,7 +67,7 @@ checking of rcu_dereference() primitives: The rcu_dereference_check() check expression can be any boolean expression, but would normally include a lockdep expression. However, any boolean expression can be used. For a moderately ornate example, -consider the following: +consider the following:: file = rcu_dereference_check(fdt->fd[fd], lockdep_is_held(&files->file_lock) || @@ -82,7 +86,7 @@ RCU read-side critical sections, in case (2) the ->file_lock prevents any change from taking place, and finally, in case (3) the current task is the only task accessing the file_struct, again preventing any change from taking place. If the above statement was invoked only from updater -code, it could instead be written as follows: +code, it could instead be written as follows:: file = rcu_dereference_protected(fdt->fd[fd], lockdep_is_held(&files->file_lock) || @@ -105,7 +109,7 @@ false and they are called from outside any RCU read-side critical section. For example, the workqueue for_each_pwq() macro is intended to be used either within an RCU read-side critical section or with wq->mutex held. -It is thus implemented as follows: +It is thus implemented as follows:: #define for_each_pwq(pwq, wq) list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node,