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Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , "Paul E. McKenney" , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Josh Poimboeuf , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?iso-8859-1?Q?Wei=DFschuh?= , Juri Lelli , Daniel Bristot de Oliveira , Marcelo Tosatti , Yair Podemsky Subject: Re: [RFC PATCH 11/14] context-tracking: Introduce work deferral infrastructure Message-ID: <20230705224104.GE2813335@hirez.programming.kicks-ass.net> References: <20230705181256.3539027-1-vschneid@redhat.com> <20230705181256.3539027-12-vschneid@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Stat-Signature: 6qdgx1xhm5gqy85cmjakfcq88qxw8sqg X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 3A9C2A0006 X-HE-Tag: 1688596888-17407 X-HE-Meta: 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 9aPjsUS6 ZqA9e641dmkUiSNhfCyo28J0O6QT5g26kH7RuoSdKPUMF9hcvbUpN2hn4jrCRe64X/vWR0ayGVI6NHPTG2zID0MhUbZNgFKRh/BDu3OjPWbRenqJAiGCd3i5KxxkUHw2CuGMeKZ9aMkjG76g= 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 Thu, Jul 06, 2023 at 12:23:57AM +0200, Frederic Weisbecker wrote: > If this is just about a dozen, can we stuff them in the state like in the > following? We can potentially add more of them especially on 64 bits we could > afford 30 different works, this is just shrinking the RCU extended quiescent > state counter space. Worst case that can happen is that RCU misses 65535 > idle/user <-> kernel transitions and delays a grace period... We can make all this a 64bit only feature and use atomic_long_t :-)