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b=PXZvhX1w3Q62MTgCQdbJwIzKCTZAbIVyDIh5ZVc9+h/W0uHbN4coaZ2M576QpPmcF ZwODhKRuqrtC+ZCBGrGeDVESVsTq4POkW2uP29xytbdEHRAuV0nBI3sK5OODMfdDAP ZL4ig4pnFtyEGwb5s+F9TvGSggB8e66DD6OcUjt3hMZyHC8uX93cuDdlemV5iKo1Eg ZPS8cOHA0dx3yK2XIo6DK71UVECo1A0NMQZZ7JwFHp1jcnEJErYLsZW1qLS2wF6kQR 4fLfr7kHSY+kQu1tVaLJC+GBLnoxrp8dhMOsei1Vw6qvGRSG/n7/8B4Ql4RYzYVP23 kG833FD/mPU1Q== Message-ID: Date: Thu, 18 Jun 2026 14:38:47 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] mm/lruvec: trace LRU add drains and drain-all requests To: "Vlastimil Babka (SUSE)" , Shakeel Butt Cc: JP Kobryn , linux-mm@kvack.org, willy@infradead.org, usama.arif@linux.dev, akpm@linux-foundation.org, mhocko@suse.com, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, kasong@tencent.com, qi.zheng@linux.dev, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, chrisl@kernel.org, shikemeng@huaweicloud.com, nphamcs@gmail.com, baoquan.he@linux.dev, youngjun.park@lge.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <20260610195220.12403-1-jp.kobryn@linux.dev> <06122cae-e28b-4ded-a9dd-d380d31c5230@kernel.org> <1136baf3-3967-4202-9eaa-5fd667c235cf@kernel.org> <3149bc84-dd3a-43ba-826e-6364965fdafd@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam07 X-Rspam-User: X-Stat-Signature: a9xhpkzpg5ypdq3x3acs5cbxpg6etr8b X-Rspamd-Queue-Id: 94D0780012 X-HE-Tag: 1781786336-785546 X-HE-Meta: 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 IAaE26ep f4toDKiPmsktXkg4y/IrPoq2JJyPylidRgTN75Z8X+WowlCy1ZolaPCvDjHYmBh8V7krR7PtHyc2kDF+OjS2/MgDwgzcXPEHDAB9gsZmEiJilzG+jvPLT6aPc1SLXN4lOoSJ6jEtSHg8hL34cxbpBKMYm6RRf6lUd5DoF5HsBY0ggxmaQHD/UdS/pMzNR/4r6xT0LDfLfGCUIWuDyJEu+t+jjqExDy2B5Ppd3wRFAWt9sddbbgM+gx7jT7DGSVumnZViGXII5hLla5fY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/18/26 10:30, Vlastimil Babka (SUSE) wrote: > On 6/18/26 10:21, David Hildenbrand (Arm) wrote: >> On 6/17/26 20:18, Vlastimil Babka (SUSE) wrote: >>> >>> Yeah and I don't recall ever that a change to a mm tracepoint would ever >>> break someone who'd complain and we'd have to revert it. >> Really? :) >> >> Read the context of the link I posted once more. > > Ah, I see. I've only read the single mail from Steven that referred to the > old powertop breakage and didn't notice the context. > > But I don't think these worries should stop us from adding easily usable > tracepoints. Steve explained a way how apparently scheduler people are handling it without trace events. You can always remove/modify tracepoints, but not trace events. Anyhow, just wanted to mention it, because so far MM didn't rally know about this implication. -- Cheers, David