From: tip-bot for Thomas Gleixner <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: torvalds@linux-foundation.org, hpa@zytor.com, tglx@linutronix.de,
rostedt@goodmis.org, mingo@kernel.org, ddaney@caviumnetworks.com,
mark.rutland@arm.com, peterz@infradead.org,
linux-kernel@vger.kernel.org, will.deacon@arm.com,
bigeasy@linutronix.de
Subject: [tip:locking/core] locking/rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL
Date: Fri, 2 Dec 2016 02:46:16 -0800 [thread overview]
Message-ID: <tip-b5016e8203003c44264ec88fe2276ff54a51f689@git.kernel.org> (raw)
In-Reply-To: <20161130210030.509567906@linutronix.de>
Commit-ID: b5016e8203003c44264ec88fe2276ff54a51f689
Gitweb: http://git.kernel.org/tip/b5016e8203003c44264ec88fe2276ff54a51f689
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Wed, 30 Nov 2016 21:04:44 +0000
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 2 Dec 2016 11:13:57 +0100
locking/rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL
This is a left over from the original rtmutex implementation which used
both bit0 and bit1 in the owner pointer. Commit:
8161239a8bcc ("rtmutex: Simplify PI algorithm and make highest prio task get lock")
... removed the usage of bit1, but kept the extra mask around. This is
confusing at best.
Remove it and just use RT_MUTEX_HAS_WAITERS for the masking.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20161130210030.509567906@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/locking/rtmutex_common.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index e317e1c..9901346 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -71,13 +71,12 @@ task_top_pi_waiter(struct task_struct *p)
* lock->owner state tracking:
*/
#define RT_MUTEX_HAS_WAITERS 1UL
-#define RT_MUTEX_OWNER_MASKALL 1UL
static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock)
{
unsigned long owner = (unsigned long) READ_ONCE(lock->owner);
- return (struct task_struct *) (owner & ~RT_MUTEX_OWNER_MASKALL);
+ return (struct task_struct *) (owner & ~RT_MUTEX_HAS_WAITERS);
}
/*
next prev parent reply other threads:[~2016-12-02 10:46 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-30 21:04 [patch 0/4] rtmutex: Plug unlock vs. requeue race Thomas Gleixner
2016-11-30 21:04 ` [patch 1/4] rtmutex: Prevent dequeue vs. unlock race Thomas Gleixner
2016-12-01 17:56 ` David Daney
2016-12-01 18:25 ` Peter Zijlstra
2016-12-02 8:18 ` Thomas Gleixner
2016-12-02 0:53 ` Steven Rostedt
2016-12-02 10:45 ` [tip:locking/core] locking/rtmutex: " tip-bot for Thomas Gleixner
2016-11-30 21:04 ` [patch 2/4] rtmutex: Use READ_ONCE() in rt_mutex_owner() Thomas Gleixner
2016-12-02 10:45 ` [tip:locking/core] locking/rtmutex: " tip-bot for Thomas Gleixner
2016-11-30 21:04 ` [patch 3/4] rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL Thomas Gleixner
2016-12-02 10:46 ` tip-bot for Thomas Gleixner [this message]
2016-11-30 21:04 ` [patch 4/4] rtmutex: Explain locking rules for rt_mutex_proxy_unlock()/init_proxy_locked() Thomas Gleixner
2016-12-02 10:46 ` [tip:locking/core] locking/rtmutex: " tip-bot for Thomas Gleixner
2016-12-01 18:33 ` [patch 0/4] rtmutex: Plug unlock vs. requeue race Peter Zijlstra
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=tip-b5016e8203003c44264ec88fe2276ff54a51f689@git.kernel.org \
--to=tipbot@zytor.com \
--cc=bigeasy@linutronix.de \
--cc=ddaney@caviumnetworks.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=will.deacon@arm.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.