x86/topology: Add CPUID.1F multi-die/package support

Some new systems have multiple software-visible die within each package.

Update Linux parsing of the Intel CPUID "Extended Topology Leaf" to handle
either CPUID.B, or the new CPUID.1F.

Add cpuinfo_x86.die_id and cpuinfo_x86.max_dies to store the result.

die_id will be non-zero only for multi-die/package systems.

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-doc@vger.kernel.org
Link: https://lkml.kernel.org/r/7b23d2d26d717b8e14ba137c94b70943f1ae4b5c.1557769318.git.len.brown@intel.com

diff --git a/Documentation/x86/topology.rst b/Documentation/x86/topology.rst
index 6e28dbe818ab122d32dbecd9a03b569f04cb5894..8e9704f6101755ba5626117603c2cfd06f396484 100644 (file)
--- a/Documentation/x86/topology.rst
+++ b/Documentation/x86/topology.rst
@@ -49,6 +49,10 @@ Package-related topology information in the kernel:
 
     The number of cores in a package. This information is retrieved via CPUID.
 
+  - cpuinfo_x86.x86_max_dies:
+
+    The number of dies in a package. This information is retrieved via CPUID.
+
   - cpuinfo_x86.phys_proc_id:
 
     The physical ID of the package. This information is retrieved via CPUID

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index c34a35c786185c3161aa7defa1c1714feacd43de..ef0a44fccaecd3dff7ffc1cbbc0c4a3786ebbe50 100644 (file)
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -105,7 +105,8 @@ struct cpuinfo_x86 {
        int                     x86_power;
        unsigned long           loops_per_jiffy;
        /* cpuid returned max cores value: */
-       u16                      x86_max_cores;
+       u16                     x86_max_cores;
+       u16                     x86_max_dies;
        u16                     apicid;
        u16                     initial_apicid;
        u16                     x86_clflush_size;
@@ -117,6 +118,7 @@ struct cpuinfo_x86 {
        u16                     logical_proc_id;
        /* Core id: */
        u16                     cpu_core_id;
+       u16                     cpu_die_id;
        /* Index into per_cpu list: */
        u16                     cpu_index;
        u32                     microcode;

diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c
index 8f6c784141d1197a38cd88a50f8abeb4f144b693..4d17e699657d684f34c11085f0cfbc00a1b7be43 100644 (file)
--- a/arch/x86/kernel/cpu/topology.c
+++ b/arch/x86/kernel/cpu/topology.c
@@ -15,33 +15,63 @@
 /* leaf 0xb SMT level */
 #define SMT_LEVEL      0
 
-/* leaf 0xb sub-leaf types */
+/* extended topology sub-leaf types */
 #define INVALID_TYPE   0
 #define SMT_TYPE       1
 #define CORE_TYPE      2
+#define DIE_TYPE       5
 
 #define LEAFB_SUBTYPE(ecx)             (((ecx) >> 8) & 0xff)
 #define BITS_SHIFT_NEXT_LEVEL(eax)     ((eax) & 0x1f)
 #define LEVEL_MAX_SIBLINGS(ebx)                ((ebx) & 0xffff)
 
-int detect_extended_topology_early(struct cpuinfo_x86 *c)
-{
 #ifdef CONFIG_SMP
+/*
+ * Check if given CPUID extended toplogy "leaf" is implemented
+ */
+static int check_extended_topology_leaf(int leaf)
+{
        unsigned int eax, ebx, ecx, edx;
 
-       if (c->cpuid_level < 0xb)
+       cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+
+       if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
                return -1;
 
-       cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+       return 0;
+}
+/*
+ * Return best CPUID Extended Toplogy Leaf supported
+ */
+static int detect_extended_topology_leaf(struct cpuinfo_x86 *c)
+{
+       if (c->cpuid_level >= 0x1f) {
+               if (check_extended_topology_leaf(0x1f) == 0)
+                       return 0x1f;
+       }
 
-       /*
-        * check if the cpuid leaf 0xb is actually implemented.
-        */
-       if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
+       if (c->cpuid_level >= 0xb) {
+               if (check_extended_topology_leaf(0xb) == 0)
+                       return 0xb;
+       }
+
+       return -1;
+}
+#endif
+
+int detect_extended_topology_early(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+       unsigned int eax, ebx, ecx, edx;
+       int leaf;
+
+       leaf = detect_extended_topology_leaf(c);
+       if (leaf < 0)
                return -1;
 
        set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
 
+       cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
        /*
         * initial apic id, which also represents 32-bit extended x2apic id.
         */
@@ -52,7 +82,7 @@ int detect_extended_topology_early(struct cpuinfo_x86 *c)
 }
 
 /*
- * Check for extended topology enumeration cpuid leaf 0xb and if it
+ * Check for extended topology enumeration cpuid leaf, and if it
  * exists, use it for populating initial_apicid and cpu topology
  * detection.
  */
@@ -60,22 +90,28 @@ int detect_extended_topology(struct cpuinfo_x86 *c)
 {
 #ifdef CONFIG_SMP
        unsigned int eax, ebx, ecx, edx, sub_index;
-       unsigned int ht_mask_width, core_plus_mask_width;
+       unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width;
        unsigned int core_select_mask, core_level_siblings;
+       unsigned int die_select_mask, die_level_siblings;
+       int leaf;
 
-       if (detect_extended_topology_early(c) < 0)
+       leaf = detect_extended_topology_leaf(c);
+       if (leaf < 0)
                return -1;
 
        /*
         * Populate HT related information from sub-leaf level 0.
         */
-       cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+       cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+       c->initial_apicid = edx;
        core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx);
        core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+       die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+       die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
 
        sub_index = 1;
        do {
-               cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx);
+               cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx);
 
                /*
                 * Check for the Core type in the implemented sub leaves.
@@ -83,23 +119,34 @@ int detect_extended_topology(struct cpuinfo_x86 *c)
                if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
                        core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
                        core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
-                       break;
+                       die_level_siblings = core_level_siblings;
+                       die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+               }
+               if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) {
+                       die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+                       die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
                }
 
                sub_index++;
        } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);
 
        core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width;
-
-       c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width)
-                                                & core_select_mask;
-       c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, core_plus_mask_width);
+       die_select_mask = (~(-1 << die_plus_mask_width)) >>
+                               core_plus_mask_width;
+
+       c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid,
+                               ht_mask_width) & core_select_mask;
+       c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid,
+                               core_plus_mask_width) & die_select_mask;
+       c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,
+                               die_plus_mask_width);
        /*
         * Reinit the apicid, now that we have extended initial_apicid.
         */
        c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
 
        c->x86_max_cores = (core_level_siblings / smp_num_siblings);
+       c->x86_max_dies = (die_level_siblings / core_level_siblings);
 #endif
        return 0;
 }

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 73e69aaaa11740fdcd8d9ed12805831a8369c8d4..40ffe23249c06bc78055e6c2b0c0a8b64e0809ab 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -389,6 +389,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
                int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
 
                if (c->phys_proc_id == o->phys_proc_id &&
+                   c->cpu_die_id == o->cpu_die_id &&
                    per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {
                        if (c->cpu_core_id == o->cpu_core_id)
                                return topology_sane(c, o, "smt");
@@ -400,6 +401,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
                }
 
        } else if (c->phys_proc_id == o->phys_proc_id &&
+                  c->cpu_die_id == o->cpu_die_id &&
                   c->cpu_core_id == o->cpu_core_id) {
                return topology_sane(c, o, "smt");
        }