Commit 6b2942f9 authored by Babu Moger's avatar Babu Moger Committed by Eduardo Habkost
Browse files

i386: Remove generic SMT thread check 



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: default avatarBabu Moger <babu.moger@amd.com>
Tested-by: default avatarGeoffrey McRae <geoff@hostfission.com>
Reviewed-by: default avatarEduardo Habkost <ehabkost@redhat.com>
Message-Id: <1529443919-67509-4-git-send-email-babu.moger@amd.com>
Signed-off-by: default avatarEduardo Habkost <ehabkost@redhat.com>
parent e0051647

target/i386/cpu.c

+11 −6
Original line number Diff line number Diff line
@@ -4985,17 +4985,22 @@ 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(%d). Please configure -smp "

                         "options properly or try enabling topoext feature.",

                         cs->nr_threads);

        ht_warned = true;

    }