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Date: Thu, 14 Nov 2024 16:14:00 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: yongli-oc <yongli-oc@zhaoxin.com>
Cc: <linux-kernel@vger.kernel.org>, <yongli@zhaoxin.com>,
 <cobechen@zhaoxin.com>, <louisqi@zhaoxin.com>, <jiangbowang@zhaoxin.com>
Subject: Re: [PATCH] Support lockref reference count if enable LOCK_STAT
Message-Id: <20241114161400.72259c36cca41c0c2da6d971@linux-foundation.org>
In-Reply-To: <20241113085703.148839-1-yongli-oc@zhaoxin.com>
References: <20241113085703.148839-1-yongli-oc@zhaoxin.com>
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On Wed, 13 Nov 2024 16:57:03 +0800 yongli-oc <yongli-oc@zhaoxin.com> wrote:

> Swap the positions of lock and count to support CMPXCHG_LOCKREF
> if SPINLOCK_SIZE > 4 when enable LOCK_STAT. The reference count
> can always be used regardless of the spinlock_t size.

Please fully describe the problem we're solving here?  And what are the
runtime effects of this change?