From mboxrd@z Thu Jan 1 00:00:00 1970 From: Babu Moger Subject: [PATCH v4 5/5] target/i386: Remove generic SMT thread check Date: Mon, 12 Mar 2018 17:00:49 -0400 Message-ID: <1520888449-4352-6-git-send-email-babu.moger@amd.com> References: <1520888449-4352-1-git-send-email-babu.moger@amd.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Thomas.Lendacky@amd.com, brijesh.singh@amd.com, kvm@vger.kernel.org, kash@tripleback.net, mtosatti@redhat.com, Gary.Hook@amd.com, qemu-devel@nongnu.org, babu.moger@amd.com To: pbonzini@redhat.com, rth@twiddle.net, ehabkost@redhat.com, rkrcmar@redhat.com Return-path: In-Reply-To: <1520888449-4352-1-git-send-email-babu.moger@amd.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel2=m.gmane.org@nongnu.org Sender: "Qemu-devel" List-Id: kvm.vger.kernel.org Remove generic non-intel check while validating hyperthreading support. Certain AMD CPUs can support hyperthreading now. CPU family with TOPOEXT feature can support hyperthreading now. Signed-off-by: Babu Moger --- target/i386/cpu.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index ade272e..10970b7 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -4330,17 +4330,20 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp) qemu_init_vcpu(cs); - /* Only Intel CPUs support hyperthreading. Even though QEMU fixes this - * issue by adjusting CPUID_0000_0001_EBX and CPUID_8000_0008_ECX - * based on inputs (sockets,cores,threads), it is still better to gives + /* Most Intel and certain AMD CPUs support hyperthreading. Even though QEMU + * fixes this issue by adjusting CPUID_0000_0001_EBX and CPUID_8000_0008_ECX + * based on inputs (sockets,cores,threads), it is still better to give * users a warning. * * NOTE: the following code has to follow qemu_init_vcpu(). Otherwise * cs->nr_threads hasn't be populated yet and the checking is incorrect. */ - if (!IS_INTEL_CPU(env) && cs->nr_threads > 1 && !ht_warned) { - error_report("AMD CPU doesn't support hyperthreading. Please configure" - " -smp options properly."); + if (IS_AMD_CPU(env) && + !(env->features[FEAT_8000_0001_ECX] & CPUID_EXT3_TOPOEXT) && + cs->nr_threads > 1 && !ht_warned) { + error_report("This family of AMD CPU doesn't support " + "hyperthreading. Please configure -smp " + "options properly."); ht_warned = true; } -- 1.8.3.1