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Wed, 22 Apr 2020 16:54:02 -0700 (PDT) Date: Wed, 22 Apr 2020 16:53:56 -0700 From: Sami Tolvanen To: Will Deacon Subject: Re: [PATCH v12 03/12] scs: add support for stack usage debugging Message-ID: <20200422235356.GA128062@google.com> References: <20191018161033.261971-1-samitolvanen@google.com> <20200421021453.198187-1-samitolvanen@google.com> <20200421021453.198187-4-samitolvanen@google.com> <20200422174602.GB3121@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200422174602.GB3121@willie-the-truck> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200422_165404_912044_4EB47EBA X-CRM114-Status: GOOD ( 11.47 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Juri Lelli , kernel-hardening@lists.openwall.com, Peter Zijlstra , Catalin Marinas , Marc Zyngier , Masahiro Yamada , clang-built-linux@googlegroups.com, Ingo Molnar , Laura Abbott , Dave Martin , Kees Cook , Jann Horn , Steven Rostedt , linux-arm-kernel@lists.infradead.org, Michal Marek , Ard Biesheuvel , Nick Desaulniers , linux-kernel@vger.kernel.org, Miguel Ojeda , James Morse , Masami Hiramatsu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Apr 22, 2020 at 06:46:02PM +0100, Will Deacon wrote: > > +static void scs_check_usage(struct task_struct *tsk) > > +{ > > + static unsigned long highest; > > + unsigned long used = __scs_used(tsk); > > + unsigned long prev; > > + unsigned long curr = highest; > > + > > + while (used > curr) { > > + prev = cmpxchg(&highest, curr, used); > > I think this can be cmpxchg_relaxed(), since we don't care about ordering > here afaict. Sure, I'll change this in v13. Thanks. Sami _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel