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charset=iso-8859-15 Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: B7C8F10000B X-Stat-Signature: 7yyg5b6nsdis3wek6co6rrac6fy9pyhx X-HE-Tag: 1684136334-294674 X-HE-Meta: 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 qgf8iTTe DK0vz4I5VFeyAXNo/U0ylXs8mBHiUEoAJ3AMGtz58aB14qIrnLjZ88soR3Aw/A+3MsOEy5jI9EQXHY1A9qDEjetSOgiyULiR/xznxFZmNtNSv8hVXxMpVWhz5Nxeg7pni80d5EPlrrDV4AFBg91Ems3yRSKKMFWQiwdp9fdIGtJY0LneTNcZM98PVEJyijkwRO4yPprnpHl1sHYM= 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: On Sun, May 14, 2023 at 09:28:56AM +0900, Tetsuo Handa wrote: > Commit 73444bc4d8f9 ("mm, page_alloc: do not wake kswapd with zone lock > held") moved wakeup_kswapd() from steal_suitable_fallback() to rmqueue() > using ZONE_BOOSTED_WATERMARK flag. > > Only allocation contexts that include ALLOC_KSWAPD (which corresponds to > __GFP_KSWAPD_RECLAIM) should wake kswapd, for callers are supposed to > remove __GFP_KSWAPD_RECLAIM if trying to hold pgdat->kswapd_wait has a > risk of deadlock. kswapd_wait is a waitqueue so what is being held? It's safe for kswapd to try wake itself as the waitqueue will be active when wakeup_kswapd() is called so no wakeup occurs. If there is a deadlock, it needs a better explanation. I believe I already stated why this patch is fixing a bug but it wasn't deadlock related. -- Mel Gorman SUSE Labs