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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     "zhaoyang.huang" <zhaoyang.huang@unisoc.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Zhaoyang Huang <huangzhaoyang@gmail.com>,
        linux-kernel@vger.kernel.org, xuewen.yan@unisoc.com,
        ke.wang@unisoc.com, ben.dai@unisoc.com, shian.wang@unisoc.com,
        linux-rt-users@vger.kernel.org
Subject: Re: [RFC PATCH] kernel: locking: rwsem optimization for rtlinux
Message-ID: <YnuDqYz5vlFw3lZy@linutronix.de>
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On 2022-05-11 16:21:21 [+0800], zhaoyang.huang wrote:
> From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> 
> With regard to rtlinux, releasing the lock to RT waiter could be helpful to
> increase its responding time even if cfs writer listed at the head of the
> wait_list.

This does not apply to current kernel (v5.18-rc6). If you need want to
apply some thing to an older kernel, I suggest a backport and reasoning
why this backport is needed.
So first you need address the issue, that you are facing, in the current
development kernel.
Also it would be good to know if "rtlinux" is PREEMPT_RT or something
else. The latter uses a different mechanism.

> Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>

Sebastian