From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48997) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bIwxy-0006Xu-D5 for qemu-devel@nongnu.org; Fri, 01 Jul 2016 07:50:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bIwxx-0006wX-BA for qemu-devel@nongnu.org; Fri, 01 Jul 2016 07:50:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52009) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bIwxw-0006wG-PT for qemu-devel@nongnu.org; Fri, 01 Jul 2016 07:50:37 -0400 From: Igor Mammedov Date: Fri, 1 Jul 2016 13:50:25 +0200 Message-Id: <1467373826-110305-5-git-send-email-imammedo@redhat.com> In-Reply-To: <1467373826-110305-1-git-send-email-imammedo@redhat.com> References: <1467373826-110305-1-git-send-email-imammedo@redhat.com> Subject: [Qemu-devel] [PATCH v3 4/5] acpi: provide _PXM method for CPU devices if QEMU is started numa enabled List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: mst@redhat.com, zhaoshenglong@huawei.com, peter.maydell@linaro.org, david@gibson.dropbear.id.au, marcel@redhat.com Workaround for long standing issue where Linux kernel assigns hotplugged CPU to 1st numa node as it discards proximity for possible CPUs from SRAT after it's parsed. _PXM method allows linux query proximity directly from hotplugged CPU object, which allows Linux to assing CPU to the correct numa node. Signed-off-by: Igor Mammedov Reviewed-by: Marcel Apfelbaum --- v3: - use numa_get_node_for_cpu() instead of duplicating lookup code - added comment in code blaming linux --- hw/acpi/cpu.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/hw/acpi/cpu.c b/hw/acpi/cpu.c index c13b65c..902f5c9 100644 --- a/hw/acpi/cpu.c +++ b/hw/acpi/cpu.c @@ -4,6 +4,7 @@ #include "qapi/error.h" #include "qapi-event.h" #include "trace.h" +#include "sysemu/numa.h" #define ACPI_CPU_HOTPLUG_REG_LEN 12 #define ACPI_CPU_SELECTOR_OFFSET_WR 0 @@ -503,6 +504,7 @@ void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts, /* build Processor object for each processor */ for (i = 0; i < arch_ids->len; i++) { + int j; Aml *dev; Aml *uid = aml_int(i); GArray *madt_buf = g_array_new(0, 1, 1); @@ -546,6 +548,16 @@ void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts, aml_arg(1), aml_arg(2)) ); aml_append(dev, method); + + /* Linux guests discard SRAT info for non-present CPUs + * as a result _PXM is required for all CPUs which might + * be hot-plugged. For simplicity, add it for all CPUs. + */ + j = numa_get_node_for_cpu(i); + if (j < nb_numa_nodes) { + aml_append(dev, aml_name_decl("_PXM", aml_int(j))); + } + aml_append(cpus_dev, dev); } } -- 1.8.3.1