From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51030) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1byYEi-0002xG-W9 for qemu-devel@nongnu.org; Mon, 24 Oct 2016 01:55:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1byYEi-0004hH-55 for qemu-devel@nongnu.org; Mon, 24 Oct 2016 01:55:53 -0400 From: vijay.kilari@gmail.com Date: Mon, 24 Oct 2016 11:25:20 +0530 Message-Id: <1477288523-10819-1-git-send-email-vijay.kilari@gmail.com> Subject: [Qemu-devel] [PATCH v3 0/3] Live migration optimization for Thunderx platform List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org, peter.maydell@linaro.org, pbonzini@redhat.com, rth@twiddle.net Cc: qemu-devel@nongnu.org, vijay.kilari@gmail.com, Vijaya Kumar K From: Vijaya Kumar K The CPU MIDR_EL1 register is exposed to userspace for arm64 with the below patch. https://lkml.org/lkml/2016/7/8/467 Thunderx platform requires explicit prefetch instruction to provide prefetch hint. Using MIDR_EL1 information, provided by above kernel patch, prefetch is executed if the platform is Thunderx. The results of live migration time improvement is provided in commit message of patch 2. Note: Check for size of while prefetching beyond page is not added. Making this check is counter productive on performance of live migration. v2 => v3: - Rebased on top of richard's patches. - Consider cache line size and line number to prefetch - Passed optional parameters to __builtin_prefetch v1 => v2: - Rename util/cpuinfo.c as util/aarch64-cpuid.c - Introduced header file include/qemu/aarch64-cpuid.h - Place all arch specific code under define __aarch64__ and CONFIG_LINUX. - Used builtin_prefetch() to add prefetch instruction. - Moved arch specific changes out of generic code - Dropped prefetching 5th cache line. Vijaya Kumar K (3): cutils: Set __builtin_prefetch optional parameters utils: Add helper to read arm MIDR_EL1 register utils: Add prefetch for Thunderx platform include/qemu/aarch64-cpuid.h | 9 +++++ util/Makefile.objs | 1 + util/aarch64-cpuid.c | 87 ++++++++++++++++++++++++++++++++++++++++++++ util/bufferiszero.c | 45 ++++++++++++++++++++--- 4 files changed, 137 insertions(+), 5 deletions(-) create mode 100644 include/qemu/aarch64-cpuid.h create mode 100644 util/aarch64-cpuid.c -- 1.9.1