From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53946) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZkRVQ-0004GS-5g for qemu-devel@nongnu.org; Fri, 09 Oct 2015 02:50:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZkRVM-0000CG-R7 for qemu-devel@nongnu.org; Fri, 09 Oct 2015 02:50:16 -0400 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:43780) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZkRVM-00009i-5Q for qemu-devel@nongnu.org; Fri, 09 Oct 2015 02:50:12 -0400 Received: from /spool/local by e28smtp06.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 9 Oct 2015 12:20:10 +0530 Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by d28dlp02.in.ibm.com (Postfix) with ESMTP id 629C63940053 for ; Fri, 9 Oct 2015 12:20:06 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay01.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t996o4On9109976 for ; Fri, 9 Oct 2015 12:20:05 +0530 Received: from d28av04.in.ibm.com (localhost [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t996o3G7024098 for ; Fri, 9 Oct 2015 12:20:04 +0530 From: Bharata B Rao Date: Fri, 9 Oct 2015 12:19:59 +0530 Message-Id: <1444373400-18423-2-git-send-email-bharata@linux.vnet.ibm.com> In-Reply-To: <1444373400-18423-1-git-send-email-bharata@linux.vnet.ibm.com> References: <1444373400-18423-1-git-send-email-bharata@linux.vnet.ibm.com> Subject: [Qemu-devel] [RFC v1 1/2] spapr: Accommadate alignment gaps in hotplug memory region List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: imammedo@redhat.com, mst@redhat.com, Bharata B Rao , david@gibson.dropbear.id.au Accommodate enough space in hotplug memory region so that it will be possible to align memory in each slot to 256M. When PowerPC memory hotplug enables inter-dimm gaps, then we could end up having unused/unassigned 256M memory chuck between DIMMs in the hotplug memory region. Hence create DRC objects spanning the entire alignment-adjusted hotplug memory region instead of just the acutal hotpluggable size (machine->maxram_size - machine->ram_size). In addition, pass 256M alignment to pc_dimm_memory_plug() so that the DIMM address gets aligned to 256M. Signed-off-by: Bharata B Rao --- hw/ppc/spapr.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index fc5e7d6..4a901f0 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -721,7 +721,7 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) int ret, i, offset; uint64_t lmb_size = SPAPR_MEMORY_BLOCK_SIZE; uint32_t prop_lmb_size[] = {0, cpu_to_be32(lmb_size)}; - uint32_t nr_lmbs = (machine->maxram_size - machine->ram_size)/lmb_size; + uint32_t nr_lmbs = memory_region_size(&spapr->hotplug_memory.mr)/lmb_size; uint32_t *int_buf, *cur_index, buf_len; int nr_nodes = nb_numa_nodes ? nb_numa_nodes : 1; @@ -1614,9 +1614,8 @@ static void spapr_drc_reset(void *opaque) static void spapr_create_lmb_dr_connectors(sPAPRMachineState *spapr) { - MachineState *machine = MACHINE(spapr); uint64_t lmb_size = SPAPR_MEMORY_BLOCK_SIZE; - uint32_t nr_lmbs = (machine->maxram_size - machine->ram_size)/lmb_size; + uint32_t nr_lmbs = memory_region_size(&spapr->hotplug_memory.mr)/lmb_size; int i; for (i = 0; i < nr_lmbs; i++) { @@ -1792,6 +1791,20 @@ static void ppc_spapr_init(MachineState *machine) spapr->hotplug_memory.base = ROUND_UP(machine->ram_size, SPAPR_HOTPLUG_MEM_ALIGN); + + /* + * Ensure that there is enough space in the hotplug memory + * region to support a maximum alignment of 256M per slot. + * Though PowerPC has 16M and 16G huge pages, PowerKVM supports + * only 16M and hence 256M alignment works until we start + * supporting 1G hugepage. + * + * Instead of max hugepage size alignment, we go with 256M + * alignment because we require the DIMM address to be 256M + * aligned as we maintain DRC objects for every 256M memory + * chunk in the hotplug memory region. + */ + hotplug_mem_size += SPAPR_MEMORY_BLOCK_SIZE * machine->ram_slots; memory_region_init(&spapr->hotplug_memory.mr, OBJECT(spapr), "hotplug-memory", hotplug_mem_size); memory_region_add_subregion(sysmem, spapr->hotplug_memory.base, @@ -2114,7 +2127,7 @@ static void spapr_memory_plug(HotplugHandler *hotplug_dev, DeviceState *dev, PCDIMMDevice *dimm = PC_DIMM(dev); PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm); MemoryRegion *mr = ddc->get_memory_region(dimm); - uint64_t align = memory_region_get_alignment(mr); + uint64_t align = SPAPR_MEMORY_BLOCK_SIZE; uint64_t size = memory_region_size(mr); uint64_t addr; -- 2.1.0