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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 0299340019 X-Stat-Signature: xqm85rkh1u9w7y95g37fo5mjhrinmk6n X-Rspam-User: X-HE-Tag: 1679126680-135165 X-HE-Meta: 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 kjj3kWZw 1qr0c2dU33vfRrrntDeGVS01xhT6YDHlB7ZWapjnBELEY9HcCjF9dCJJHdLUZsxfQNr18eQGLEjaMqgiWXxkhJsMz1UtbJLksQbKtbr7LMXsvtAL8D9M4MyBpL2LKW3UidEV4W8mlYEmBg4xxvl/MZaJYL0HEJy7yOJdJhZj9/uRz5AlyhL89uGG223xQrYtpZKKZe3V0CUsMsFrwooYpIldUJEnC1SxtLlxAKlKT8V3hXUeZMRXX2/Pw4xmNfQQsNYrDEDjiulMLZbz3KRBK+0DiNw== 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 Fri 17-03-23 15:35:05, Marcelo Tosatti wrote: > On Fri, Mar 17, 2023 at 03:33:13PM -0300, Marcelo Tosatti wrote: > > On Fri, Mar 17, 2023 at 02:44:47PM +0100, Michal Hocko wrote: > > > From: Frederic Weisbecker > > > > > > Provide this new API to check if a CPU has been isolated either through > > > isolcpus= or nohz_full= kernel parameter. > > > > > > It aims at avoiding kernel load deemed to be safely spared on CPUs > > > running sensitive workload that can't bear any disturbance, such as > > > pcp cache draining. > > > > Hi Michal, > > > > This makes no sense to me. > > > > HK_TYPE_DOMAIN is set when isolcpus=domain is configured. > > HK_TYPE_TICK is set when nohz_full= is configured. > > > > The use-cases i am aware of use either: > > > > isolcpus=managed_irq,... nohz_full= > > OR > > isolcpus=domain,managed_irq,... nohz_full= > > > > So what is the point of this function again? > > > > Perhaps it made sense along with, but now does not make sense > > anymore: > > > > Subject: [PATCH 1/2] sched/isolation: Merge individual nohz_full features into a common housekeeping flag > > > > The individual isolation features turned on by nohz_full were initially > > split in order for each of them to be tunable through cpusets. However > > plans have changed in favour of an interface (be it cpusets or sysctl) > > grouping all these features to be turned on/off altogether. Then should > > the need ever arise, the interface can still be expanded to handle the > > individual isolation features. > > > > But Michal can just use housekeeping_test_cpu(cpu, HK_TYPE_TICK) and > > the convertion of nohz_full features into a common housekeeping flag > > can convert that to something else later? > > Actually introducing cpu_is_isolated() seems fine, but it can call > housekeeping_test_cpu(cpu, HK_TYPE_TICK) AFAICS. This is not really my area. Frederic, could you have a look please? -- Michal Hocko SUSE Labs