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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: References: <20230705181256.3539027-1-vschneid@redhat.com> <20230705181256.3539027-12-vschneid@redhat.com> <20230705224104.GE2813335@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230705224104.GE2813335@hirez.programming.kicks-ass.net> X-Rspam-User: X-Stat-Signature: w4b1oa6werzkrjdqj13dxq6cdkoi3rkd X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 8FAB14001B X-HE-Tag: 1688637241-237686 X-HE-Meta: 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 a0K9kAPf o3RmCo3OgSIacGX9C5YIVCNNavVPN3btSidDzWUF3DqJSLYMfj4jHh3b1EhQ+nfNejC+BEBvIFfwe70tKp8SI76qBkSSRlxqSD7Sn9JKniRpuex9qRxOB56grX8DXh4Iy0+Z1J0+pYxEH9TtqRimtlp3gEx5h26c12HqtLmY/rvRxaNAX6/nPP+0FzCG5Mwr9EMtAM9KY6w0rX56XPsrEczVkTOPqJUyHtabBoLCrsk8eGmGtcLR3jozcVQ8x7GSxZrAgkEjTZ7L3vFJnXuOHE5EIvdZoKeK0a6V+ 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 12:41:04AM +0200, Peter Zijlstra wrote: > 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 :-) Works for me :)