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McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Uladzislau Rezki , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long , Mark Rutland , Thomas Gleixner , Kent Overstreet , Vlastimil Babka , maged.michael@gmail.com Subject: Re: [RFC PATCH 0/4] Add hazard pointers to kernel Message-ID: References: <20240917143402.930114-1-boqun.feng@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Queue-Id: 911DA18001F X-Rspamd-Server: rspam01 X-Stat-Signature: akc6tf4f6c1gortpwgk53arc3fgdegd3 X-HE-Tag: 1726755304-356593 X-HE-Meta: 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 KRnEGgcY 8ku969YNRmkp5xfyv53BWeMxKyrD0x/JikDb6pAgDleMHvzn1Ueydz8t4e/JecZiV+xE1vW9ffRY1JplsJguo/NLH/2ZpvE02WtCgWVoHL5OhvMftrpABowPUSoWO/HJ4x3geODUi6n3SNWHVPW2jSWZe4G3A2T4rcEyLlVlsYiix7pxv8rZkf3JkMI+d1JL30O0JFTnCoqfk+h9KBBeSNX2Z9XrAWufuuhz5fi3Ov0yLeuIjQu974CX6YjJNJq0WUGbtu3BqDNqrli4AoMwsJRxOI6se4A8QE/rST7bwGaEY0lmVg4ItizjS6X8512UMjZzoa7B6c0bCemJTZJQsmADGc8LHW+DfTjiwtr4PWkR9EtMT8xpXkmzch3XWXNsgRdfrKlxIxC4A3LuHPAivj57aV+dbEmjVxn4i0Ox2LQtndJKd90/WxMlsHcsc8sUa6aOn5YKrHwVlEEo1t+9IIEVufl4rRdP9P2IK99tLcjDOPvH42ehmZDId+igLxfwnDlzeX2j4U3+d4yjouBE9etdws3GBtR9mPNgW5pXMR7FsDRLCbkwhE+XnssCs6An/youi X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Sep 18, 2024 at 09:18:43AM +0200, Linus Torvalds wrote: > On Tue, 17 Sept 2024 at 16:34, Boqun Feng wrote: > > > > This series introduces hazard pointers [1] to kernel space. A TL;DR > > description of hazard pointers is "a scalable refcounting mechanim > > with RCU-like API". More information can be found at [2]. > > Please give actual "this is useful for X, and here is an actual real > load with numbers showing why it matters". Agreed. From the description this would seem like a good fit for q_usage_counter in the block layer, which currently makes creative use of percpu counters.