From: Zhao Liu <zhao1.liu@xxxxxxxxx>
In cpu_x86_cpuid(), there are many variables in representing the cpu
topology, e.g., topo_info, cs->nr_cores and 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 members clearly, thus the
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.hu@xxxxxxxxxxxxxxx>
Tested-by: Yongwei Ma <yongwei.ma@xxxxxxxxx>
Signed-off-by: Zhao Liu <zhao1.liu@xxxxxxxxx>
Reviewed-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
Changes since v7:
* Renamed cpus_per_pkg to threads_per_pkg. (Xiaoyao)
* Dropped Michael/Babu's Acked/Tested tags since the code change.
* Re-added Yongwei's Tested tag For his re-testing.
* Added Xiaoyao's Reviewed tag.
Changes since v3:
* Fixed typo. (Babu)
Changes since v1:
* Extracted cores_per_socket from the code block and use it as a local
variable for cpu_x86_cpuid(). (Yanan)
* Removed vcpus_per_socket variable and use cpus_per_pkg directly.
(Yanan)
* Replaced 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 65944645db5c..b32833f65dd6 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6016,11 +6016,16 @@ 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 threads_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;
+ threads_per_pkg = cores_per_pkg * topo_info.threads_per_core;
+
/* Calculate & apply limits for different index ranges */
if (index >= 0xC0000000) {
limit = env->cpuid_xlevel2;
@@ -6056,8 +6061,8 @@ 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 (threads_per_pkg > 1) {
+ *ebx |= threads_per_pkg << 16;
*edx |= CPUID_HT;
}
if (!cpu->enable_pmu) {
@@ -6097,15 +6102,15 @@ 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) {
addressable_cores_width = apicid_pkg_offset(&topo_info) -
apicid_core_offset(&topo_info);
*eax &= ~0xFC000000;
*eax |= ((1 << addressable_cores_width) - 1) << 26;
}
- if (host_vcpus_per_cache > vcpus_per_socket) {
+ if (host_vcpus_per_cache > threads_per_pkg) {
/* Share the cache at package level. */
addressable_threads_width = apicid_pkg_offset(&topo_info);
@@ -6251,12 +6256,12 @@ 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 = threads_per_pkg;
*ecx |= CPUID_TOPOLOGY_LEVEL_CORE;
break;
default:
@@ -6276,7 +6281,7 @@ 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;
}
@@ -6286,7 +6291,7 @@ 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:
@@ -6296,7 +6301,7 @@ 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 = threads_per_pkg;
*ecx |= CPUID_TOPOLOGY_LEVEL_DIE;
break;
default:
@@ -6520,7 +6525,7 @@ 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 (threads_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) {
@@ -6586,7 +6591,7 @@ 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 (threads_per_pkg > 1) {
/*
* Bits 15:12 is "The number of bits in the initial
* Core::X86::Apic::ApicId[ApicId] value that indicate
@@ -6594,7 +6599,7 @@ 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);
+ (threads_per_pkg - 1);
} else {
*ecx = 0;
}
--
2.34.1
