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McKenney" Cc: stern@rowland.harvard.edu, parri.andrea@gmail.com, will@kernel.org, boqun.feng@gmail.com, npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk, luc.maranget@inria.fr, akiyks@gmail.com, dlustig@nvidia.com, joel@joelfernandes.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, andriin@fb.com Subject: Re: Some -serious- BPF-related litmus tests Message-ID: <20200522094407.GK325280@hirez.programming.kicks-ass.net> References: <20200522003850.GA32698@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200522003850.GA32698@paulmck-ThinkPad-P72> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 21, 2020 at 05:38:50PM -0700, Paul E. McKenney wrote: > Hello! > > Just wanted to call your attention to some pretty cool and pretty serious > litmus tests that Andrii did as part of his BPF ring-buffer work: > > https://lore.kernel.org/bpf/20200517195727.279322-3-andriin@fb.com/ > > Thoughts? I find: smp_wmb() smp_store_release() a _very_ weird construct. What is that supposed to even do?