From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48349) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1byhPd-0002Zu-Uw for qemu-devel@nongnu.org; Mon, 24 Oct 2016 11:43:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1byhPa-0001Up-2i for qemu-devel@nongnu.org; Mon, 24 Oct 2016 11:43:46 -0400 Sender: Richard Henderson References: <1477288523-10819-1-git-send-email-vijay.kilari@gmail.com> <1477288523-10819-2-git-send-email-vijay.kilari@gmail.com> From: Richard Henderson Message-ID: Date: Mon, 24 Oct 2016 08:43:36 -0700 MIME-Version: 1.0 In-Reply-To: <1477288523-10819-2-git-send-email-vijay.kilari@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 1/3] cutils: Set __builtin_prefetch optional parameters List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: vijay.kilari@gmail.com, qemu-arm@nongnu.org, peter.maydell@linaro.org, pbonzini@redhat.com Cc: qemu-devel@nongnu.org, Vijaya Kumar K On 10/23/2016 10:55 PM, vijay.kilari@gmail.com wrote: > From: Vijaya Kumar K > > Optional parameters of __builtin_prefetch() which specifies > rw and locality to 0's. For checking buffer is zero, set rw as read > and temporal locality to 0. > > On arm64, __builtin_prefetch(addr) generates 'prfm pldl1keep' > where __builtin_prefetch(addr, 0, 0) generates 'prfm pldl1strm' > instruction which is optimal for this use case > > Signed-off-by: Vijaya Kumar K > --- Reviewed-by: Richard Henderson r~