From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33519) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bu0Xd-0001Ei-6G for qemu-devel@nongnu.org; Tue, 11 Oct 2016 13:08:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bu0Xb-00046K-35 for qemu-devel@nongnu.org; Tue, 11 Oct 2016 13:08:36 -0400 From: Peter Maydell Date: Tue, 11 Oct 2016 18:08:19 +0100 Message-Id: <1476205699-28857-8-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1476205699-28857-1-git-send-email-peter.maydell@linaro.org> References: <1476205699-28857-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PATCH v3 7/7] hw/arm/virt: Set minimum_page_bits to 12 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org, qemu-devel@nongnu.org Cc: patches@linaro.org, paolo@archaic.org.uk, Vijaya Kumar K , "Dr . David Alan Gilbert" , Laurent Desnogues , Richard Henderson Since the virt board model will never create a CPU which is pre-ARMv7, we know that our minimum page size is 4K and can set minimum_page_bits accordingly, for improved performance. Note that this is a migration compatibility break, so we introduce it only for the virt-2.8 machine and onward; virt-2.7 continues using the old 1K pages. Signed-off-by: Peter Maydell --- hw/arm/virt.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 795740d..abef00c 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -1496,6 +1496,8 @@ static void virt_machine_class_init(ObjectClass *oc, void *data) mc->block_default_type = IF_VIRTIO; mc->no_cdrom = 1; mc->pci_allow_0_address = true; + /* We know we will never create a pre-ARMv7 CPU which needs 1K pages */ + mc->minimum_page_bits = 12; } static const TypeInfo virt_machine_info = { @@ -1563,6 +1565,8 @@ static void virt_machine_2_7_options(MachineClass *mc) { virt_machine_2_8_options(mc); SET_MACHINE_COMPAT(mc, VIRT_COMPAT_2_7); + /* Stick with 1K pages for migration compatibility */ + mc->minimum_page_bits = 0; } DEFINE_VIRT_MACHINE(2, 7) -- 2.7.4