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([2601:188:c102:b180:1f8b:71d0:77b1:1f6e]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-506392902eesm99012571cf.21.2026.02.10.06.39.31 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 10 Feb 2026 06:39:31 -0800 (PST) From: Waiman Long X-Google-Original-From: Waiman Long Message-ID: Date: Tue, 10 Feb 2026 09:39:30 -0500 Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH/for-next v4 3/4] cgroup/cpuset: Call housekeeping_update() without holding cpus_read_lock To: Chen Ridong , Waiman Long , Tejun Heo , Johannes Weiner , =?UTF-8?Q?Michal_Koutn=C3=BD?= , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Anna-Maria Behnsen , Frederic Weisbecker , Thomas Gleixner , Shuah Khan Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20260206203712.1989610-1-longman@redhat.com> <20260206203712.1989610-4-longman@redhat.com> <119981d3-1cf9-412b-9b4d-bc4bcb188104@huaweicloud.com> <67f4b01a-7b23-49c2-a8db-059316300d39@redhat.com> <08776cf5-054e-4137-9ce4-f193feeb2599@huaweicloud.com> Content-Language: en-US In-Reply-To: <08776cf5-054e-4137-9ce4-f193feeb2599@huaweicloud.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2/9/26 8:39 PM, Chen Ridong wrote: > > On 2026/2/10 4:20, Waiman Long wrote: >> On 2/9/26 2:23 AM, Chen Ridong wrote: >>> On 2026/2/7 4:37, Waiman Long wrote: >>>> +static cpumask_var_t    isolated_hk_cpus;    /* T */ >>> Can we get this from isolation.c instead? >>> >>> The name probably shouldn't include 'hk', since it refers to the inverse >>> (housekeeping CPUs) of isolated CPUs, right? >> The housekeeping_update() will create an inverse of the pass-in isolated >> cpumasks. As for the name, I add hk to indicate this cpumask is for passing to >> housekeeping_update() to update housekeeping cpumask. It is not directly related >> to the cpumasks in sched/isolation.c. Please let me know if you have  a >> suggestion for the name. >> > I understand the intent. However, when reading both cpuset.c and > sched/isolation.c, it can be confusing whether isolated_hk_cpus is an inverse > mask, since in sched/isolation.c “hk” consistently refers to the inverse. > > How about isolated_cpus_applied? Applied to what? I did add a comment to describe isolated_hk_cpus as a copy of isolated_cpus to be passed to housekeeping_update(). "hk" in the name refers to its role for being passed to that function. I can't use "isolated_cpus" for now as it may get modified by CPU hotplug concurrently. In the future, if CPU hotplug no longer modify isolated_cpus, I will remove isolated_hk_cpus and pass isolated_cpus directly to housekeeping_update(). I don't think we need to spend extra time bikeshedding what the right name should be. Cheers, Longman