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b=XMhg/zvtUQbsUJj0jEEmzzEM1sOuu2PmK5XEbqJjnz8o2pgGld2ayg7B3R8Gv48Se SmstiDzpRJMQD++m9DEwq/Pu6nQPU4xv1OqaIy/PzhfSY41PXkak32EB72oP4Ti6rG uMcVYCmNg5miEcjUE3rMaaeI0s3eawFjKU9a1KMFzXzW0OereAzwNY+rHfs34M23jD KxIiqOHzrUuvw8uKG3GOmDHICi7Af+HNsA+C5PHINOKJzauazTtSt4ZdZszBLQxv8v 8Es+m9P0oiFJzZ8g+qeYVdj4nT2saQc/XKe/I1+f1XLeSyKjKCIJxedx3amZxr544i so18H0arHs96g== Message-ID: <832e4333-4079-4865-8ad8-3dd8868fb964@kernel.org> Date: Fri, 8 May 2026 19:38:09 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] mm/page_alloc: add tracepoints for zone->lock acquisitions To: Andrew Morton , hawk@kernel.org, Dmitry Ilvokhin , Matthew Wilcox Cc: linux-mm@kvack.org, Steven Rostedt , Suren Baghdasaryan , Michal Hocko , Zi Yan , David Hildenbrand , Lorenzo Stoakes , Shuah Khan , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, kernel-team@cloudflare.com References: <20260508162207.3315781-1-hawk@kernel.org> <20260508102948.b1c687e623fabec65580f258@linux-foundation.org> From: "Vlastimil Babka (SUSE)" Content-Language: en-US In-Reply-To: <20260508102948.b1c687e623fabec65580f258@linux-foundation.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 0A242120010 X-Rspam-User: X-Stat-Signature: mxkosb3ctxy9dhg937kxo9kiatyn198c X-HE-Tag: 1778261894-146860 X-HE-Meta: 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 xNDf+m/d rCPqiNAwlBHBCgqfo2LbJo0Iko1oQscExc28W/Uowotf5Yh9aYbrK0EzNW7LBpVsTBUlpi2pubW9M70q9Dzg/Monn9/okagas/8+HQt4uKnppLmiF7CF5vHeQZfbsvUxaVVtyligF5WgQj/4HDqPNSvuPF3gvLk03wneyJ7WcE6On/a+7q159suXiACoiVUbzHgWesZ/KmPnISsvjOopfvosj0THzgEQkCAfSN+CyZRQIX2PtU5rZ8GtQ1jhSnuPzjs/wGOzNyWLb6NEr6lVuAmUP6kDFi8pmK61D7vzHNfojj2rhETs7ju9gfBN31HPwazJjPAy9CXTINh1IJF3Cy2v+fYt/D8H7BeGq+eLrFhOHI8Ht6zeHy4bnueNj250yh19rJuNV07dqwmXOrMz+1XcDnhDtrv4h0D6I25udAdxO75JuvKA3WfJ35g== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 5/8/26 7:29 PM, Andrew Morton wrote: > e .configOn Fri, 8 May 2026 18:22:06 +0200 hawk@kernel.org wrote: > >> Add tracepoints to the page allocator fast paths that acquire >> zone->lock, allowing diagnosis of lock contention in production. > > Thanks, I'm surprised we haven't done this yet. There was a recent attempt [1]. Not being a generic solution wasn't welcome. [1] https://lore.kernel.org/all/cover.1772206930.git.d@ilvokhin.com/ > Unfortunately "mm: use spinlock guards for zone lock" messed this up > (https://lore.kernel.org/all/cover.1777462630.git.d@ilvokhin.com/). > > So please let's give it a few days for reviewers to comment then redo > against mm.git's mm-unstable branch?