Hi Zhao,
On 8/1/23 05:35, Zhao Liu wrote:
> From: Zhao Liu <zhao1....@intel.com>
>
> In cpu_x86_cpuid(), there are many variables in representing the cpu
> topology, e.g., topo_info, cs->nr_cores/cs->nr_threads.
>
> Since the names of cs->nr_cores/cs->nr_threads does not accurately
> represent its meaning, the use of cs->nr_cores/cs->nr_threads is prone
> to confusion and mistakes.
>
> And the structure X86CPUTopoInfo names its memebers clearly, thus the
s/memebers/members/
Thanks
Babu
> variable "topo_info" should be preferred.
>
> In addition, in cpu_x86_cpuid(), to uniformly use the topology variable,
> replace env->dies with topo_info.dies_per_pkg as well.
>
> Suggested-by: Robert Hoo <robert...@linux.intel.com>
> Signed-off-by: Zhao Liu <zhao1....@intel.com>
> ---
> Changes since v1:
> * Extract cores_per_socket from the code block and use it as a local
> variable for cpu_x86_cpuid(). (Yanan)
> * Remove vcpus_per_socket variable and use cpus_per_pkg directly.
> (Yanan)
> * Replace env->dies with topo_info.dies_per_pkg in cpu_x86_cpuid().
> ---
> target/i386/cpu.c | 31 ++++++++++++++++++-------------
> 1 file changed, 18 insertions(+), 13 deletions(-)
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index c80613bfcded..fc50bf98c60e 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -6008,11 +6008,16 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> uint32_t limit;
> uint32_t signature[3];
> X86CPUTopoInfo topo_info;
> + uint32_t cores_per_pkg;
> + uint32_t cpus_per_pkg;
>
> topo_info.dies_per_pkg = env->nr_dies;
> topo_info.cores_per_die = cs->nr_cores / env->nr_dies;
> topo_info.threads_per_core = cs->nr_threads;
>
> + cores_per_pkg = topo_info.cores_per_die * topo_info.dies_per_pkg;
> + cpus_per_pkg = cores_per_pkg * topo_info.threads_per_core;
> +
> /* Calculate & apply limits for different index ranges */
> if (index >= 0xC0000000) {
> limit = env->cpuid_xlevel2;
> @@ -6048,8 +6053,8 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> *ecx |= CPUID_EXT_OSXSAVE;
> }
> *edx = env->features[FEAT_1_EDX];
> - if (cs->nr_cores * cs->nr_threads > 1) {
> - *ebx |= (cs->nr_cores * cs->nr_threads) << 16;
> + if (cpus_per_pkg > 1) {
> + *ebx |= cpus_per_pkg << 16;
> *edx |= CPUID_HT;
> }
> if (!cpu->enable_pmu) {
> @@ -6086,8 +6091,8 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> */
> if (*eax & 31) {
> int host_vcpus_per_cache = 1 + ((*eax & 0x3FFC000) >> 14);
> - int vcpus_per_socket = cs->nr_cores * cs->nr_threads;
> - if (cs->nr_cores > 1) {
> +
> + if (cores_per_pkg > 1) {
> int addressable_cores_offset =
>
> apicid_pkg_offset(&topo_info) -
>
> apicid_core_offset(&topo_info);
> @@ -6095,7 +6100,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> *eax &= ~0xFC000000;
> *eax |= (1 << addressable_cores_offset - 1) << 26;
> }
> - if (host_vcpus_per_cache > vcpus_per_socket) {
> + if (host_vcpus_per_cache > cpus_per_pkg) {
> int pkg_offset = apicid_pkg_offset(&topo_info);
>
> *eax &= ~0x3FFC000;
> @@ -6240,12 +6245,12 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> switch (count) {
> case 0:
> *eax = apicid_core_offset(&topo_info);
> - *ebx = cs->nr_threads;
> + *ebx = topo_info.threads_per_core;
> *ecx |= CPUID_TOPOLOGY_LEVEL_SMT;
> break;
> case 1:
> *eax = apicid_pkg_offset(&topo_info);
> - *ebx = cs->nr_cores * cs->nr_threads;
> + *ebx = cpus_per_pkg;
> *ecx |= CPUID_TOPOLOGY_LEVEL_CORE;
> break;
> default:
> @@ -6266,7 +6271,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> break;
> case 0x1F:
> /* V2 Extended Topology Enumeration Leaf */
> - if (env->nr_dies < 2) {
> + if (topo_info.dies_per_pkg < 2) {
> *eax = *ebx = *ecx = *edx = 0;
> break;
> }
> @@ -6276,7 +6281,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> switch (count) {
> case 0:
> *eax = apicid_core_offset(&topo_info);
> - *ebx = cs->nr_threads;
> + *ebx = topo_info.threads_per_core;
> *ecx |= CPUID_TOPOLOGY_LEVEL_SMT;
> break;
> case 1:
> @@ -6286,7 +6291,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> break;
> case 2:
> *eax = apicid_pkg_offset(&topo_info);
> - *ebx = cs->nr_cores * cs->nr_threads;
> + *ebx = cpus_per_pkg;
> *ecx |= CPUID_TOPOLOGY_LEVEL_DIE;
> break;
> default:
> @@ -6511,7 +6516,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> * discards multiple thread information if it is set.
> * So don't set it here for Intel to make Linux guests happy.
> */
> - if (cs->nr_cores * cs->nr_threads > 1) {
> + if (cpus_per_pkg > 1) {
> if (env->cpuid_vendor1 != CPUID_VENDOR_INTEL_1 ||
> env->cpuid_vendor2 != CPUID_VENDOR_INTEL_2 ||
> env->cpuid_vendor3 != CPUID_VENDOR_INTEL_3) {
> @@ -6577,7 +6582,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> *eax |= (cpu_x86_virtual_addr_width(env) << 8);
> }
> *ebx = env->features[FEAT_8000_0008_EBX];
> - if (cs->nr_cores * cs->nr_threads > 1) {
> + if (cpus_per_pkg > 1) {
> /*
> * Bits 15:12 is "The number of bits in the initial
> * Core::X86::Apic::ApicId[ApicId] value that indicate
> @@ -6585,7 +6590,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> * Bits 7:0 is "The number of threads in the package is NC+1"
> */
> *ecx = (apicid_pkg_offset(&topo_info) << 12) |
> - ((cs->nr_cores * cs->nr_threads) - 1);
> + (cpus_per_pkg - 1);
> } else {
> *ecx = 0;
> }
--
Thanks
Babu Moger
