From: Anna-Maria Gleixner <anna-maria@linutronix.de>
To: linux-kernel@vger.kernel.org
Cc: tglx@linutronix.de, bigeasy@linutronix.de,
paulmck@linux.vnet.ibm.com, ebiederm@xmission.com,
Anna-Maria Gleixner <anna-maria@linutronix.de>
Subject: [PATCH v2 1/2] rcu: Update documentation of rcu_read_unlock()
Date: Fri, 25 May 2018 11:05:06 +0200 [thread overview]
Message-ID: <20180525090507.22248-2-anna-maria@linutronix.de> (raw)
In-Reply-To: <20180525090507.22248-1-anna-maria@linutronix.de>
Since commit b4abf91047cf ("rtmutex: Make wait_lock irq safe") the
explanation in rcu_read_unlock() documentation about irq unsafe rtmutex
wait_lock is no longer valid.
Remove it to prevent kernel developers reading the documentation to rely on
it.
Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
include/linux/rcupdate.h | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 36360d07f25b..64644fda3b22 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -653,9 +653,7 @@ static inline void rcu_read_lock(void)
* Unfortunately, this function acquires the scheduler's runqueue and
* priority-inheritance spinlocks. This means that deadlock could result
* if the caller of rcu_read_unlock() already holds one of these locks or
- * any lock that is ever acquired while holding them; or any lock which
- * can be taken from interrupt context because rcu_boost()->rt_mutex_lock()
- * does not disable irqs while taking ->wait_lock.
+ * any lock that is ever acquired while holding them.
*
* That said, RCU readers are never priority boosted unless they were
* preempted. Therefore, one way to avoid deadlock is to make sure
--
2.15.1
next prev parent reply other threads:[~2018-05-25 9:05 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-25 9:05 [PATCH v2 0/2] rtmutex wait_lock is irq safe Anna-Maria Gleixner
2018-05-25 9:05 ` Anna-Maria Gleixner [this message]
2018-05-25 14:19 ` [PATCH v2 1/2] rcu: Update documentation of rcu_read_unlock() Paul E. McKenney
2018-05-28 9:49 ` Anna-Maria Gleixner
2018-06-10 4:18 ` [tip:core/urgent] " tip-bot for Anna-Maria Gleixner
2018-05-25 9:05 ` [PATCH v2 2/2] signal: Remove no longer required irqsave/restore Anna-Maria Gleixner
2018-06-10 4:19 ` [tip:core/urgent] " tip-bot for Anna-Maria Gleixner
2018-05-25 20:02 ` [PATCH v2 0/2] rtmutex wait_lock is irq safe Eric W. Biederman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180525090507.22248-2-anna-maria@linutronix.de \
--to=anna-maria@linutronix.de \
--cc=bigeasy@linutronix.de \
--cc=ebiederm@xmission.com \
--cc=linux-kernel@vger.kernel.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).