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Date:   Thu, 5 Jan 2023 18:59:09 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Hongchen Zhang <zhanghongchen@loongson.cn>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Kuniyuki Iwashima <kuniyu@amazon.co.jp>,
        Luis Chamberlain <mcgrof@kernel.org>,
        David Howells <dhowells@redhat.com>,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        Randy Dunlap <rdunlap@infradead.org>,
        Eric Dumazet <edumazet@google.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] pipe: use __pipe_{lock,unlock} instead of spinlock
Message-Id: <20230105185909.c77ce4d136279ec46a204d61@linux-foundation.org>
In-Reply-To: <20230103063303.23345-1-zhanghongchen@loongson.cn>
References: <20230103063303.23345-1-zhanghongchen@loongson.cn>
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On Tue,  3 Jan 2023 14:33:03 +0800 Hongchen Zhang <zhanghongchen@loongson.cn> wrote:

> Use spinlock in pipe_read/write cost too much time,IMO
> pipe->{head,tail} can be protected by __pipe_{lock,unlock}.
> On the other hand, we can use __pipe_lock/unlock to protect the
> pipe->head/tail in pipe_resize_ring and post_one_notification.

Can you please test this with the test code in Linus's 0ddad21d3e99 and
check that performance is good?