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Peter Anvin" , Hugh Dickins , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Shuah Khan , Mike Rapoport , Steven Price , "Maciej S . Szmigiero" , Vlastimil Babka , Vishal Annapurve , Yu Zhang , "Kirill A . Shutemov" , luto@kernel.org, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com, aarcange@redhat.com, ddutile@redhat.com, dhildenb@redhat.com, Quentin Perret , Michael Roth , mhocko@suse.com, Muchun Song Subject: Re: [PATCH v7 08/14] KVM: Rename mmu_notifier_* Message-ID: <20230524202835.GB3447678@hirez.programming.kicks-ass.net> References: <20220706082016.2603916-1-chao.p.peng@linux.intel.com> <20220706082016.2603916-9-chao.p.peng@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: BA2F420009 X-Rspam-User: X-Stat-Signature: x5rfoufz6391doek8rciuiwghtw4o95k X-Rspamd-Server: rspam03 X-HE-Tag: 1684960193-424438 X-HE-Meta: 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 Dla+wcjE WMAz2LL5BN1/Jns+bza4Po1BWQ8j03Fyz1hc5VnXeaQvDYDnxOt5/ScA6NOhv0Qy9Xt2vnvQhA8LoEg9gc6rV39Y1dDf5tFSIFT+YY+UqtUlig6peZ1bSU6It2Idoa5Yb60Z7jq909yzYr/YNvqhf9vW3UhatJAkUK4x3O8Mq4BPT0FvQAr89mcEOTg== 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 Wed, May 24, 2023 at 11:42:15AM +0530, Kautuk Consul wrote: > My comment was based on the assumption that "all atomic operations are > implicit memory barriers". If that assumption is true then we won't need It is not -- also see Documentation/atomic_t.txt. Specifically atomic_read() doesn't imply any ordering on any architecture including the strongly ordered TSO-archs (like x86).