All of lore.kernel.org
 help / color / mirror / Atom feed
From: Alex Shi <alex.shi@linaro.org>
To: peterz@infradead.org, mingo@redhat.com,
	linux-kernel@vger.kernel.org (open list:LOCKING PRIMITIVES)
Cc: linux-kernel@vger.kernel.org, Alex Shi <alex.shi@linaro.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Sebastian Siewior <bigeasy@linutronix.de>,
	Mathieu Poirier <mathieu.poirier@linaro.org>,
	Juri Lelli <juri.lelli@arm.com>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH] rtmutex: remove unnecessary adjust prio
Date: Thu, 13 Jul 2017 14:18:24 +0800	[thread overview]
Message-ID: <1499926704-28841-1-git-send-email-alex.shi@linaro.org> (raw)

We don't need to adjust prio before new pi_waiter adding. The prio
only need update after pi_waiter change or task priority change.

Steven Rostedt pointed:
"Interesting, I did some git mining and this was added with the original
entry of the rtmutex.c (23f78d4a0). Looking at even that version, I
don't see the purpose of adjusting the task prio here. It is done
before anything changes in the task."

Signed-off-by: Alex Shi <alex.shi@linaro.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
To: linux-kernel@vger.kernel.org
To: Ingo Molnar <mingo@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/locking/rtmutex.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 28cd09e..d1fe41f 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -963,7 +963,6 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 		return -EDEADLK;
 
 	raw_spin_lock(&task->pi_lock);
-	rt_mutex_adjust_prio(task);
 	waiter->task = task;
 	waiter->lock = lock;
 	waiter->prio = task->prio;
-- 
2.7.4

             reply	other threads:[~2017-07-13  6:19 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-13  6:18 Alex Shi [this message]
2017-07-13  9:48 ` [tip:locking/urgent] locking/rtmutex: Remove unnecessary priority adjustment tip-bot for Alex Shi

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=1499926704-28841-1-git-send-email-alex.shi@linaro.org \
    --to=alex.shi@linaro.org \
    --cc=bigeasy@linutronix.de \
    --cc=juri.lelli@arm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mathieu.poirier@linaro.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --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 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.