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charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: hmccgyddqxwbu4utq8ozwm46s6xscybp X-Rspamd-Queue-Id: E0AB440005 X-HE-Tag: 1680004084-382388 X-HE-Meta: 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 lEAOmuCc qv8XGEZbuB8fTO9gMIcIFUHjyCoaXIBDRdue6jaGCFOAiRbBjFWAa8R6yyEl6soQ5278mgLm2dagtZ03jn4tfk2dtkG7ENFpsrFBQ1v5WPUY3Wm8Y408igml1jvrVfBHwiV+bSKmW7V0+VYiYS5sycsNwNCp/VhbadsW1T5n4UA4chNehdrPhvXIWkCtTrP57Wi1wM3/2ROTQSYyffoiSHcDfbA== 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 Mon 27-03-23 07:24:54, Marcelo Tosatti wrote: > On Fri, Mar 24, 2023 at 11:35:35PM +0100, Frederic Weisbecker wrote: > > Le Sat, Mar 18, 2023 at 09:04:38AM +0100, Michal Hocko a écrit : > > > On Fri 17-03-23 15:35:05, Marcelo Tosatti wrote: [...] > > > > 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? > > > > The point is to have a function that tells if either nohz_full= or > > isolcpus=[domain] has been passed for the given CPU. > > > > Because I assumed that both would be interested in avoiding that flush > > noise, wouldn't it be the case? > > Yes, that is the case. But as a note: for the two main types of > configuration performed (one uses isolcpus=[domain] and the other > cgroups, for isolating processes) nohz_full= is always set. > > So just testing for nohz_full= would be sufficient (which perhaps would > make the code simpler). I do not see any mention about that assumption under Documentation/. Is this a best practice documented anywhere or it just happens to be the case with workloads you deal with? -- Michal Hocko SUSE Labs