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Fri, 08 May 2026 04:33:18 -0700 (PDT) From: Zijiang Huang X-Google-Original-From: Zijiang Huang To: chrisl@kernel.org Cc: albinwyang@tencent.com, baoquan.he@linux.dev, bhe@redhat.com, flyingpeng@tencent.com, huangzjsmile@gmail.com, kasong@tencent.com, kerayhuang@tencent.com, linux-mm@kvack.org Subject: Re: [PATCH v2] mm/swap: Add cond_resched() in swap_reclaim_full_clusters to prevent softlockup Date: Fri, 8 May 2026 19:33:00 +0800 Message-ID: <20260508113300.3977280-1-kerayhuang@tencent.com> X-Mailer: git-send-email 2.43.7 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: tjmmydztiwkcr3xancjix5amg8g73gso X-Rspam-User: X-Rspamd-Queue-Id: 1ADAD40007 X-Rspamd-Server: rspam07 X-HE-Tag: 1778239999-280207 X-HE-Meta: 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 yVVZLVhs fnDXz95TYcTchnA8gtA2sPCGbkGIpyW0GsrO1KfzZ8hpvvgFePsHXtkAZUUhyWTSaF7SFzWn/kB9dgg7SNM0qf9kEejTJ3i5K4C2fLY7s2tvh6WR6Gq0KoWiNaTd4Y21gkVceGBn67xUfCas5dctcI01ZWgCooeGaDyAwpNnOeXFDwHa3rVWeN+xeL/WHoJk4sArLKwT8qjIs7fh3KZSElKDpL9js7m2SS/64MzkfvZMNW2NN9TbV7twuM0ygyWGfnufTg13rAK3u2/OFY3ltYMRs7n0TPFjQs6WKUfNcRaL8/e30tAKFFWBu33it5qpgr0H6qyc9KHjBcEAK/u48HLC5U8SxX5v/nHeMits9ug2uhxKIk8qr5uuJep6CH/LQYq5WajOwhLxqCIve5T/nuCc7PrWGgr8N5+PRKTbzGbEiJ/I6jkUdkqaFLr001Wzn0E06 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: >On Wed, May 6, 2026 at 4:56=E2=80=AFPM Zijiang Huang m> wrote: >> >> We hit a real softlockup in an internal stress test environment. >> The workload was LTP memory/swap stress on a large arm64 machine, >> with 320 CPUs, about 1TB memory and an 8.6GB swap device. >> The system was under heavy load and the swap device had a large >> number of full clusters. The softlockup was triggered during >> a stress test after about 3 days. >> >> So, add periodic cond_resched() calls during large full_clusters >> reclaim operations to prevent softlockup issues. >Thank you for reporting and fixing this issue. > >Can you add that to the patch commit log? This background information >is very important for the reader why this change is needed. > >Assume you will update the commit log. > >Acked-by: Chris Li > >Chris Hi Chris, I've updated the commit log with the background information in v2. Thanks!