From: "Mi, Dapeng" <dapeng1.mi@linux.intel.com>
To: "Zhao Liu" <zhao1.liu@intel.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Marcelo Tosatti" <mtosatti@redhat.com>,
"Michael S . Tsirkin" <mst@redhat.com>,
"Daniel P . Berrangé" <berrange@redhat.com>,
"Igor Mammedov" <imammedo@redhat.com>,
"Marcel Apfelbaum" <marcel.apfelbaum@gmail.com>,
"Richard Henderson" <richard.henderson@linaro.org>,
"Eduardo Habkost" <eduardo@habkost.net>
Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org>,
"Babu Moger" <babu.moger@amd.com>,
"Ewan Hai" <ewanhai-oc@zhaoxin.com>, "Pu Wen" <puwen@hygon.cn>,
"Tao Su" <tao1.su@intel.com>, "Yi Lai" <yi1.lai@intel.com>,
"Dapeng Mi" <dapeng1.mi@intel.com>,
qemu-devel@nongnu.org, kvm@vger.kernel.org
Subject: Re: [PATCH 16/16] i386/cpu: Use a unified cache_info in X86CPUState
Date: Thu, 3 Jul 2025 16:53:50 +0800 [thread overview]
Message-ID: <3d1f5698-1936-4fc0-af04-db900f0d1b9e@linux.intel.com> (raw)
In-Reply-To: <20250620092734.1576677-17-zhao1.liu@intel.com>
On 6/20/2025 5:27 PM, Zhao Liu wrote:
> At present, all cases using the cache model (CPUID 0x2, 0x4, 0x80000005,
> 0x80000006 and 0x8000001D leaves) have been verified to be able to
> select either cache_info_intel or cache_info_amd based on the vendor.
>
> Therefore, further merge cache_info_intel and cache_info_amd into a
> unified cache_info in X86CPUState, and during its initialization, set
> different legacy cache models based on the vendor.
>
> Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
> ---
> target/i386/cpu.c | 150 ++++++++--------------------------------------
> target/i386/cpu.h | 5 +-
> 2 files changed, 27 insertions(+), 128 deletions(-)
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 4e9ac37850c0..c1d1289ee9de 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -7484,27 +7484,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> } else if (env->enable_legacy_vendor_cache) {
> caches = &legacy_intel_cache_info;
> } else {
> - /*
> - * FIXME: Temporarily select cache info model here based on
> - * vendor, and merge these 2 cache info models later.
> - *
> - * This condition covers the following cases (with
> - * enable_legacy_vendor_cache=false):
> - * - When CPU model has its own cache model and doesn't use legacy
> - * cache model (legacy_model=off). Then cache_info_amd and
> - * cache_info_cpuid4 are the same.
> - *
> - * - For v10.1 and newer machines, when CPU model uses legacy cache
> - * model. Non-AMD CPUs use cache_info_cpuid4 like before and AMD
> - * CPU will use cache_info_amd. But this doesn't matter for AMD
> - * CPU, because this leaf encodes all-0 for AMD whatever its cache
> - * model is.
> - */
> - if (IS_AMD_CPU(env)) {
> - caches = &env->cache_info_amd;
> - } else {
> - caches = &env->cache_info_cpuid4;
> - }
> + caches = &env->cache_info;
> }
>
> if (cpu->cache_info_passthrough) {
> @@ -7523,27 +7503,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> if (env->enable_legacy_vendor_cache) {
> caches = &legacy_intel_cache_info;
> } else {
> - /*
> - * FIXME: Temporarily select cache info model here based on
> - * vendor, and merge these 2 cache info models later.
> - *
> - * This condition covers the following cases (with
> - * enable_legacy_vendor_cache=false):
> - * - When CPU model has its own cache model and doesn't use legacy
> - * cache model (legacy_model=off). Then cache_info_amd and
> - * cache_info_cpuid4 are the same.
> - *
> - * - For v10.1 and newer machines, when CPU model uses legacy cache
> - * model. Non-AMD CPUs use cache_info_cpuid4 like before and AMD
> - * CPU will use cache_info_amd. But this doesn't matter for AMD
> - * CPU, because this leaf encodes all-0 for AMD whatever its cache
> - * model is.
> - */
> - if (IS_AMD_CPU(env)) {
> - caches = &env->cache_info_amd;
> - } else {
> - caches = &env->cache_info_cpuid4;
> - }
> + caches = &env->cache_info;
> }
>
> /* cache info: needed for Core compatibility */
> @@ -7951,27 +7911,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> if (env->enable_legacy_vendor_cache) {
> caches = &legacy_amd_cache_info;
> } else {
> - /*
> - * FIXME: Temporarily select cache info model here based on
> - * vendor, and merge these 2 cache info models later.
> - *
> - * This condition covers the following cases (with
> - * enable_legacy_vendor_cache=false):
> - * - When CPU model has its own cache model and doesn't uses legacy
> - * cache model (legacy_model=off). Then cache_info_amd and
> - * cache_info_cpuid4 are the same.
> - *
> - * - For v10.1 and newer machines, when CPU model uses legacy cache
> - * model. AMD CPUs use cache_info_amd like before and non-AMD
> - * CPU will use cache_info_cpuid4. But this doesn't matter,
> - * because for Intel CPU, it will get all-0 leaf, and Zhaoxin CPU
> - * will get correct cache info. Both are expected.
> - */
> - if (IS_AMD_CPU(env)) {
> - caches = &env->cache_info_amd;
> - } else {
> - caches = &env->cache_info_cpuid4;
> - }
> + caches = &env->cache_info;
> }
>
> if (cpu->cache_info_passthrough) {
> @@ -7998,25 +7938,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> if (env->enable_legacy_vendor_cache) {
> caches = &legacy_amd_cache_info;
> } else {
> - /*
> - * FIXME: Temporarily select cache info model here based on
> - * vendor, and merge these 2 cache info models later.
> - *
> - * This condition covers the following cases (with
> - * enable_legacy_vendor_cache=false):
> - * - When CPU model has its own cache model and doesn't uses legacy
> - * cache model (legacy_model=off). Then cache_info_amd and
> - * cache_info_cpuid4 are the same.
> - *
> - * - For v10.1 and newer machines, when CPU model uses legacy cache
> - * model. AMD CPUs use cache_info_amd like before and non-AMD
> - * CPU (Intel & Zhaoxin) will use cache_info_cpuid4 as expected.
> - */
> - if (IS_AMD_CPU(env)) {
> - caches = &env->cache_info_amd;
> - } else {
> - caches = &env->cache_info_cpuid4;
> - }
> + caches = &env->cache_info;
> }
>
> if (cpu->cache_info_passthrough) {
> @@ -8089,22 +8011,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> *edx = 0;
> }
> break;
> - case 0x8000001D: {
> - const CPUCaches *caches;
> -
> - /*
> - * FIXME: Temporarily select cache info model here based on
> - * vendor, and merge these 2 cache info models later.
> - *
> - * Intel doesn't support this leaf so that Intel Guests don't
> - * have this leaf. This change is harmless to Intel CPUs.
> - */
> - if (IS_AMD_CPU(env)) {
> - caches = &env->cache_info_amd;
> - } else {
> - caches = &env->cache_info_cpuid4;
> - }
> -
> + case 0x8000001D:
> *eax = 0;
> if (cpu->cache_info_passthrough) {
> x86_cpu_get_cache_cpuid(index, count, eax, ebx, ecx, edx);
> @@ -8112,19 +8019,19 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> }
> switch (count) {
> case 0: /* L1 dcache info */
> - encode_cache_cpuid8000001d(caches->l1d_cache,
> + encode_cache_cpuid8000001d(env->cache_info.l1d_cache,
> topo_info, eax, ebx, ecx, edx);
> break;
> case 1: /* L1 icache info */
> - encode_cache_cpuid8000001d(caches->l1i_cache,
> + encode_cache_cpuid8000001d(env->cache_info.l1i_cache,
> topo_info, eax, ebx, ecx, edx);
> break;
> case 2: /* L2 cache info */
> - encode_cache_cpuid8000001d(caches->l2_cache,
> + encode_cache_cpuid8000001d(env->cache_info.l2_cache,
> topo_info, eax, ebx, ecx, edx);
> break;
> case 3: /* L3 cache info */
> - encode_cache_cpuid8000001d(caches->l3_cache,
> + encode_cache_cpuid8000001d(env->cache_info.l3_cache,
> topo_info, eax, ebx, ecx, edx);
> break;
> default: /* end of info */
> @@ -8135,7 +8042,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
> *edx &= CACHE_NO_INVD_SHARING | CACHE_INCLUSIVE;
> }
> break;
> - }
> case 0x8000001E:
> if (cpu->core_id <= 255) {
> encode_topo_cpuid8000001e(cpu, topo_info, eax, ebx, ecx, edx);
> @@ -8825,46 +8731,34 @@ static bool x86_cpu_update_smp_cache_topo(MachineState *ms, X86CPU *cpu,
>
> level = machine_get_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L1D);
> if (level != CPU_TOPOLOGY_LEVEL_DEFAULT) {
> - env->cache_info_cpuid4.l1d_cache->share_level = level;
> - env->cache_info_amd.l1d_cache->share_level = level;
> + env->cache_info.l1d_cache->share_level = level;
> } else {
> machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L1D,
> - env->cache_info_cpuid4.l1d_cache->share_level);
> - machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L1D,
> - env->cache_info_amd.l1d_cache->share_level);
> + env->cache_info.l1d_cache->share_level);
> }
>
> level = machine_get_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L1I);
> if (level != CPU_TOPOLOGY_LEVEL_DEFAULT) {
> - env->cache_info_cpuid4.l1i_cache->share_level = level;
> - env->cache_info_amd.l1i_cache->share_level = level;
> + env->cache_info.l1i_cache->share_level = level;
> } else {
> machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L1I,
> - env->cache_info_cpuid4.l1i_cache->share_level);
> - machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L1I,
> - env->cache_info_amd.l1i_cache->share_level);
> + env->cache_info.l1i_cache->share_level);
> }
>
> level = machine_get_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L2);
> if (level != CPU_TOPOLOGY_LEVEL_DEFAULT) {
> - env->cache_info_cpuid4.l2_cache->share_level = level;
> - env->cache_info_amd.l2_cache->share_level = level;
> + env->cache_info.l2_cache->share_level = level;
> } else {
> machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L2,
> - env->cache_info_cpuid4.l2_cache->share_level);
> - machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L2,
> - env->cache_info_amd.l2_cache->share_level);
> + env->cache_info.l2_cache->share_level);
> }
>
> level = machine_get_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L3);
> if (level != CPU_TOPOLOGY_LEVEL_DEFAULT) {
> - env->cache_info_cpuid4.l3_cache->share_level = level;
> - env->cache_info_amd.l3_cache->share_level = level;
> + env->cache_info.l3_cache->share_level = level;
> } else {
> machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L3,
> - env->cache_info_cpuid4.l3_cache->share_level);
> - machine_set_cache_topo_level(ms, CACHE_LEVEL_AND_TYPE_L3,
> - env->cache_info_amd.l3_cache->share_level);
> + env->cache_info.l3_cache->share_level);
> }
>
> if (!machine_check_smp_cache(ms, errp)) {
> @@ -9091,7 +8985,7 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
> "CPU model '%s' doesn't support legacy-cache=off", name);
> return;
> }
> - env->cache_info_cpuid4 = env->cache_info_amd = *cache_info;
> + env->cache_info = *cache_info;
> } else {
> /* Build legacy cache information */
> if (!cpu->consistent_cache) {
> @@ -9101,8 +8995,12 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
> if (!cpu->vendor_cpuid_only_v2) {
> env->enable_legacy_vendor_cache = true;
> }
> - env->cache_info_cpuid4 = legacy_intel_cache_info;
> - env->cache_info_amd = legacy_amd_cache_info;
> +
> + if (IS_AMD_CPU(env)) {
> + env->cache_info = legacy_amd_cache_info;
> + } else {
> + env->cache_info = legacy_intel_cache_info;
> + }
> }
>
> #ifndef CONFIG_USER_ONLY
> diff --git a/target/i386/cpu.h b/target/i386/cpu.h
> index 243383efd602..3f79db679888 100644
> --- a/target/i386/cpu.h
> +++ b/target/i386/cpu.h
> @@ -2072,11 +2072,12 @@ typedef struct CPUArchState {
> /* Features that were explicitly enabled/disabled */
> FeatureWordArray user_features;
> uint32_t cpuid_model[12];
> - /* Cache information for CPUID. When legacy-cache=on, the cache data
> + /*
> + * Cache information for CPUID. When legacy-cache=on, the cache data
> * on each CPUID leaf will be different, because we keep compatibility
> * with old QEMU versions.
> */
> - CPUCaches cache_info_cpuid4, cache_info_amd;
> + CPUCaches cache_info;
> bool enable_legacy_cpuid2_cache;
> bool enable_legacy_vendor_cache;
>
Nice clean-up patch series. Thanks.
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
next prev parent reply other threads:[~2025-07-03 8:53 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-20 9:27 [PATCH 00/16] i386/cpu: Unify the cache model in X86CPUState Zhao Liu
2025-06-20 9:27 ` [PATCH 01/16] i386/cpu: Refine comment of CPUID2CacheDescriptorInfo Zhao Liu
2025-07-02 8:48 ` Mi, Dapeng
2025-07-03 7:38 ` Zhao Liu
2025-06-20 9:27 ` [PATCH 02/16] i386/cpu: Add descriptor 0x49 for CPUID 0x2 encoding Zhao Liu
2025-07-02 9:04 ` Mi, Dapeng
2025-07-03 7:39 ` Zhao Liu
2025-06-20 9:27 ` [PATCH 03/16] i386/cpu: Add default cache model for Intel CPUs with level < 4 Zhao Liu
2025-07-02 9:53 ` Mi, Dapeng
2025-07-03 7:47 ` Zhao Liu
2025-06-20 9:27 ` [PATCH 04/16] i386/cpu: Present same cache model in CPUID 0x2 & 0x4 Zhao Liu
2025-07-03 4:14 ` Mi, Dapeng
2025-07-03 6:35 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 05/16] i386/cpu: Consolidate CPUID 0x4 leaf Zhao Liu
2025-06-26 12:10 ` Ewan Hai
2025-06-27 2:44 ` Zhao Liu
2025-07-03 6:41 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 06/16] i386/cpu: Drop CPUID 0x2 specific cache info in X86CPUState Zhao Liu
2025-07-03 7:03 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 07/16] i386/cpu: Mark CPUID[0x80000005] as reserved for Intel Zhao Liu
2025-07-03 7:07 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 08/16] i386/cpu: Fix CPUID[0x80000006] for Intel CPU Zhao Liu
2025-07-03 7:09 ` Mi, Dapeng
2025-07-03 7:52 ` Zhao Liu
2025-06-20 9:27 ` [PATCH 09/16] i386/cpu: Add legacy_intel_cache_info cache model Zhao Liu
2025-07-03 7:15 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 10/16] i386/cpu: Add legacy_amd_cache_info " Zhao Liu
2025-07-03 7:18 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 11/16] i386/cpu: Select legacy cache model based on vendor in CPUID 0x2 Zhao Liu
2025-07-03 8:47 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 12/16] i386/cpu: Select legacy cache model based on vendor in CPUID 0x4 Zhao Liu
2025-07-03 8:49 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 13/16] i386/cpu: Select legacy cache model based on vendor in CPUID 0x80000005 Zhao Liu
2025-07-03 8:52 ` Mi, Dapeng
2025-06-20 9:27 ` [PATCH 14/16] i386/cpu: Select legacy cache model based on vendor in CPUID 0x80000006 Zhao Liu
2025-06-20 9:27 ` [PATCH 15/16] i386/cpu: Select legacy cache model based on vendor in CPUID 0x8000001D Zhao Liu
2025-06-20 9:27 ` [PATCH 16/16] i386/cpu: Use a unified cache_info in X86CPUState Zhao Liu
2025-07-03 8:53 ` Mi, Dapeng [this message]
2025-07-03 9:50 ` Zhao Liu
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