| Message ID | 20240627-add-cpu-type-v2-3-f927bde83ad0@linux.intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Add CPU-type to topology | expand |
On 6/28/2024 4:44 AM, Pawan Gupta wrote: > get_this_hybrid_cpu_type() misses a case when cpu-type is populated > regardless of X86_FEATURE_HYBRID_CPU. This is particularly true for hybrid > variants that have P or E cores fused off. > > Instead use topology_hw_cpu_type() as it does not rely on hybrid feature to > enumerate cpu-type. This can also help avoid the model-specific fixup > get_hybrid_cpu_type(). > > Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> > Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> > --- > arch/x86/events/intel/core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c > index 38c1b1f1deaa..0da1fd14b0ea 100644 > --- a/arch/x86/events/intel/core.c > +++ b/arch/x86/events/intel/core.c > @@ -4753,7 +4753,7 @@ static void intel_pmu_check_hybrid_pmus(struct x86_hybrid_pmu *pmu) > > static struct x86_hybrid_pmu *find_hybrid_pmu_for_cpu(void) > { > - u8 cpu_type = get_this_hybrid_cpu_type(); > + u8 cpu_type = topology_hw_cpu_type(smp_processor_id()); As Kan said, ARL-H would have two different atom uarchs, so we have to use the extra native model id to identify them for PMU enabling. I'm not sure if we need a similar helper topology_hw_cpu_native_id(), it may depend on if the native id needs to be exposed to user space? such as whether there are different vulnerabilities between these two atom uarchs? For PMU enabling, we don't need to expose the native model ID to user space, so we define a new helper get_this_hybrid_cpu_native_id() and leverage it to identify the atom uarch. > int i; > > /* >
On Fri, Jun 28, 2024 at 04:59:18PM +0800, Mi, Dapeng wrote: > > On 6/28/2024 4:44 AM, Pawan Gupta wrote: > > get_this_hybrid_cpu_type() misses a case when cpu-type is populated > > regardless of X86_FEATURE_HYBRID_CPU. This is particularly true for hybrid > > variants that have P or E cores fused off. > > > > Instead use topology_hw_cpu_type() as it does not rely on hybrid feature to > > enumerate cpu-type. This can also help avoid the model-specific fixup > > get_hybrid_cpu_type(). > > > > Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> > > Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> > > --- > > arch/x86/events/intel/core.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c > > index 38c1b1f1deaa..0da1fd14b0ea 100644 > > --- a/arch/x86/events/intel/core.c > > +++ b/arch/x86/events/intel/core.c > > @@ -4753,7 +4753,7 @@ static void intel_pmu_check_hybrid_pmus(struct x86_hybrid_pmu *pmu) > > > > static struct x86_hybrid_pmu *find_hybrid_pmu_for_cpu(void) > > { > > - u8 cpu_type = get_this_hybrid_cpu_type(); > > + u8 cpu_type = topology_hw_cpu_type(smp_processor_id()); > > As Kan said, ARL-H would have two different atom uarchs, so we have to use > the extra native model id to identify them for PMU enabling. I'm not sure > if we need a similar helper topology_hw_cpu_native_id(), it may depend on > if the native id needs to be exposed to user space? such as whether there > are different vulnerabilities between these two atom uarchs? > > For PMU enabling, we don't need to expose the native model ID to user > space, so we define a new helper get_this_hybrid_cpu_native_id() and > leverage it to identify the atom uarch. As CPUID.1A.EAX returns both the native model ID and core type, we can store it raw in topo->hw_cpu_type. Such that topo->hw_cpu_type contains both the native model ID and core-type. Then use accessors to get them separately? As per Intel SDM Vol 2A, table 3-8, combination of core-type and native model ID identifies the microarchitecture uniquely: EAX Enumerates the native model ID and core type. Bits 31-24: Core type* 10H: Reserved 20H: Intel Atom® 30H: Reserved 40H: Intel® Core™ Bits 23-00: Native model ID of the core. The core-type and native model ID can be used to uniquely identify the microarchitecture of the core. Let me know if below patch that implements intel_get_native_model_id() would work for your use case: --- diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index 20e491c22b98..eaa84e4e4771 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -26,11 +26,13 @@ int mwait_usable(const struct cpuinfo_x86 *); unsigned int x86_family(unsigned int sig); unsigned int x86_model(unsigned int sig); unsigned int x86_stepping(unsigned int sig); +enum x86_hw_topo_cpu_type x86_get_hw_cpu_type(struct cpuinfo_x86 *c); #ifdef CONFIG_CPU_SUP_INTEL extern void __init sld_setup(struct cpuinfo_x86 *c); extern bool handle_user_split_lock(struct pt_regs *regs, long error_code); extern bool handle_guest_split_lock(unsigned long ip); extern void handle_bus_lock(struct pt_regs *regs); +u32 intel_get_native_model_id(struct cpuinfo_x86 *c); #else static inline void __init sld_setup(struct cpuinfo_x86 *c) {} static inline bool handle_user_split_lock(struct pt_regs *regs, long error_code) @@ -44,6 +46,7 @@ static inline bool handle_guest_split_lock(unsigned long ip) } static inline void handle_bus_lock(struct pt_regs *regs) {} +u32 intel_get_native_model_id(struct cpuinfo_x86 *c) { return 0; } #endif #ifdef CONFIG_IA32_FEAT_CTL void init_ia32_feat_ctl(struct cpuinfo_x86 *c); diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index d8d715fcc25c..08794668750f 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -107,7 +107,7 @@ struct cpuinfo_topology { u32 l2c_id; // Hardware defined CPU-type - u8 hw_cpu_type; + u32 hw_cpu_type; }; struct cpuinfo_x86 { diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h index 717fdb928dc3..70f1a9661ce3 100644 --- a/arch/x86/include/asm/topology.h +++ b/arch/x86/include/asm/topology.h @@ -33,8 +33,6 @@ #include <linux/numa.h> #include <linux/cpumask.h> -#define X86_CPU_TYPE_INTEL_SHIFT 24 - enum x86_hw_topo_cpu_type { X86_HW_CPU_TYPE_UNKNOWN = 0, X86_HW_CPU_TYPE_INTEL_ATOM = 0x20, diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 86e0c69a60f6..151c2377df21 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1292,6 +1292,11 @@ static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long whi return m && !!(m->driver_data & which); } +enum x86_hw_topo_cpu_type __weak x86_get_hw_cpu_type(struct cpuinfo_x86 *c) +{ + return X86_HW_CPU_TYPE_UNKNOWN; +} + u64 x86_read_arch_cap_msr(void) { u64 x86_arch_cap_msr = 0; diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index ac6c68a39051..3a951632d210 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -1335,3 +1335,16 @@ void __init sld_setup(struct cpuinfo_x86 *c) sld_state_setup(); sld_state_show(); } + +#define X86_INTEL_CPU_TYPE_SHIFT 24 +#define X86_INTEL_NATIVE_MODEL_ID_MASK ((1 << X86_INTEL_CPU_TYPE_SHIFT) - 1) + +enum x86_hw_topo_cpu_type x86_get_hw_cpu_type(struct cpuinfo_x86 *c) +{ + return c->topo.hw_cpu_type >> X86_INTEL_CPU_TYPE_SHIFT; +} + +u32 intel_get_native_model_id(struct cpuinfo_x86 *c) +{ + return c->topo.hw_cpu_type & X86_INTEL_NATIVE_MODEL_ID_MASK; +} diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c index 85ef17325c06..8493bcd4db0b 100644 --- a/arch/x86/kernel/cpu/match.c +++ b/arch/x86/kernel/cpu/match.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include <asm/cpu_device_id.h> #include <asm/cpufeature.h> +#include <asm/cpu.h> #include <linux/cpu.h> #include <linux/export.h> #include <linux/slab.h> @@ -22,7 +23,7 @@ static bool x86_match_hw_cpu_type(struct cpuinfo_x86 *c, const struct x86_cpu_id if (boot_cpu_has(X86_FEATURE_HYBRID_CPU)) return true; - return c->topo.hw_cpu_type == m->cpu_type; + return m->cpu_type == x86_get_hw_cpu_type(c); } /** diff --git a/arch/x86/kernel/cpu/topology_common.c b/arch/x86/kernel/cpu/topology_common.c index 8b47bd6b0623..819f850b1960 100644 --- a/arch/x86/kernel/cpu/topology_common.c +++ b/arch/x86/kernel/cpu/topology_common.c @@ -87,6 +87,7 @@ static void parse_topology(struct topo_scan *tscan, bool early) .cu_id = 0xff, .llc_id = BAD_APICID, .l2c_id = BAD_APICID, + .hw_cpu_type = X86_HW_CPU_TYPE_UNKNOWN, }; struct cpuinfo_x86 *c = tscan->c; struct { @@ -132,6 +133,8 @@ static void parse_topology(struct topo_scan *tscan, bool early) case X86_VENDOR_INTEL: if (!IS_ENABLED(CONFIG_CPU_SUP_INTEL) || !cpu_parse_topology_ext(tscan)) parse_legacy(tscan); + if (c->cpuid_level >= 0x1a) + c->topo.hw_cpu_type = cpuid_eax(0x1a); break; case X86_VENDOR_HYGON: if (IS_ENABLED(CONFIG_CPU_SUP_HYGON)) @@ -140,14 +143,6 @@ static void parse_topology(struct topo_scan *tscan, bool early) } } -static void topo_set_hw_cpu_type(struct cpuinfo_x86 *c) -{ - c->topo.hw_cpu_type = X86_HW_CPU_TYPE_UNKNOWN; - - if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 0x1a) - c->topo.hw_cpu_type = cpuid_eax(0x1a) >> X86_CPU_TYPE_INTEL_SHIFT; -} - static void topo_set_ids(struct topo_scan *tscan, bool early) { struct cpuinfo_x86 *c = tscan->c; @@ -198,7 +193,6 @@ void cpu_parse_topology(struct cpuinfo_x86 *c) } topo_set_ids(&tscan, false); - topo_set_hw_cpu_type(c); } void __init cpu_init_topology(struct cpuinfo_x86 *c)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 38c1b1f1deaa..0da1fd14b0ea 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -4753,7 +4753,7 @@ static void intel_pmu_check_hybrid_pmus(struct x86_hybrid_pmu *pmu) static struct x86_hybrid_pmu *find_hybrid_pmu_for_cpu(void) { - u8 cpu_type = get_this_hybrid_cpu_type(); + u8 cpu_type = topology_hw_cpu_type(smp_processor_id()); int i; /*
get_this_hybrid_cpu_type() misses a case when cpu-type is populated regardless of X86_FEATURE_HYBRID_CPU. This is particularly true for hybrid variants that have P or E cores fused off. Instead use topology_hw_cpu_type() as it does not rely on hybrid feature to enumerate cpu-type. This can also help avoid the model-specific fixup get_hybrid_cpu_type(). Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> --- arch/x86/events/intel/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)