x86/topology: Create logical package id

For per package oriented services we must be able to rely on the number of CPU
packages to be within bounds. Create a tracking facility, which

- calculates the number of possible packages depending on nr_cpu_ids after boot

- makes sure that the package id is within the number of possible packages. If
  the apic id is outside we map it to a logical package id if there is enough
  space available.

Provide interfaces for drivers to query the mapping and do translations from
physcial to logical ids.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160222221011.541071755@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 20c11d1..813384e 100644 (file)
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -129,6 +129,8 @@ struct cpuinfo_x86 {
        u16                     booted_cores;
        /* Physical processor id: */
        u16                     phys_proc_id;
+       /* Logical processor id: */
+       u16                     logical_proc_id;
        /* Core id: */
        u16                     cpu_core_id;
        /* Compute unit id */

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index 0fb4648..7f991bd 100644 (file)
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -119,12 +119,23 @@ static inline void setup_node_to_cpumask_map(void) { }
 
 extern const struct cpumask *cpu_coregroup_mask(int cpu);
 
+#define topology_logical_package_id(cpu)       (cpu_data(cpu).logical_proc_id)
 #define topology_physical_package_id(cpu)      (cpu_data(cpu).phys_proc_id)
 #define topology_core_id(cpu)                  (cpu_data(cpu).cpu_core_id)
 
 #ifdef ENABLE_TOPO_DEFINES
 #define topology_core_cpumask(cpu)             (per_cpu(cpu_core_map, cpu))
 #define topology_sibling_cpumask(cpu)          (per_cpu(cpu_sibling_map, cpu))
+
+extern unsigned int __max_logical_packages;
+#define topology_max_packages()                        (__max_logical_packages)
+int topology_update_package_map(unsigned int apicid, unsigned int cpu);
+extern int topology_phys_to_logical_pkg(unsigned int pkg);
+#else
+#define topology_max_packages()                        (1)
+static inline int
+topology_update_package_map(unsigned int apicid, unsigned int cpu) { return 0; }
+static inline int topology_phys_to_logical_pkg(unsigned int pkg) { return 0; }
 #endif
 
 static inline void arch_fix_phys_package_id(int num, u32 slot)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 8a5cdda..531b961 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2077,6 +2077,20 @@ int generic_processor_info(int apicid, int version)
        } else
                cpu = cpumask_next_zero(-1, cpu_present_mask);
 
+       /*
+        * This can happen on physical hotplug. The sanity check at boot time
+        * is done from native_smp_prepare_cpus() after num_possible_cpus() is
+        * established.
+        */
+       if (topology_update_package_map(apicid, cpu) < 0) {
+               int thiscpu = max + disabled_cpus;
+
+               pr_warning("ACPI: Package limit reached. Processor %d/0x%x ignored.\n",
+                          thiscpu, apicid);
+               disabled_cpus++;
+               return -ENOSPC;
+       }
+
        /*
         * Validate version
         */

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 68a80e9..81cf716 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -975,6 +975,8 @@ static void identify_cpu(struct cpuinfo_x86 *c)
 #ifdef CONFIG_NUMA
        numa_add_cpu(smp_processor_id());
 #endif
+       /* The boot/hotplug time assigment got cleared, restore it */
+       c->logical_proc_id = topology_phys_to_logical_pkg(c->phys_proc_id);
 }
 
 /*

diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 05b9211..38766c2 100644 (file)
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -160,6 +160,19 @@ static void early_init_intel(struct cpuinfo_x86 *c)
                pr_info("Disabling PGE capability bit\n");
                setup_clear_cpu_cap(X86_FEATURE_PGE);
        }
+
+       if (c->cpuid_level >= 0x00000001) {
+               u32 eax, ebx, ecx, edx;
+
+               cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
+               /*
+                * If HTT (EDX[28]) is set EBX[16:23] contain the number of
+                * apicids which are reserved per package. Store the resulting
+                * shift value for the package management code.
+                */
+               if (edx & (1U << 28))
+                       c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
+       }
 }
 
 #ifdef CONFIG_X86_32

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 24d57f7..3bf1e0b 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -97,6 +97,14 @@ DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map);
 DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
 EXPORT_PER_CPU_SYMBOL(cpu_info);
 
+/* Logical package management. We might want to allocate that dynamically */
+static int *physical_to_logical_pkg __read_mostly;
+static unsigned long *physical_package_map __read_mostly;;
+static unsigned long *logical_package_map  __read_mostly;
+static unsigned int max_physical_pkg_id __read_mostly;
+unsigned int __max_logical_packages __read_mostly;
+EXPORT_SYMBOL(__max_logical_packages);
+
 static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
 {
        unsigned long flags;
@@ -251,6 +259,97 @@ static void notrace start_secondary(void *unused)
        cpu_startup_entry(CPUHP_ONLINE);
 }
 
+int topology_update_package_map(unsigned int apicid, unsigned int cpu)
+{
+       unsigned int new, pkg = apicid >> boot_cpu_data.x86_coreid_bits;
+
+       /* Called from early boot ? */
+       if (!physical_package_map)
+               return 0;
+
+       if (pkg >= max_physical_pkg_id)
+               return -EINVAL;
+
+       /* Set the logical package id */
+       if (test_and_set_bit(pkg, physical_package_map))
+               goto found;
+
+       if (pkg < __max_logical_packages) {
+               set_bit(pkg, logical_package_map);
+               physical_to_logical_pkg[pkg] = pkg;
+               goto found;
+       }
+       new = find_first_zero_bit(logical_package_map, __max_logical_packages);
+       if (new >= __max_logical_packages) {
+               physical_to_logical_pkg[pkg] = -1;
+               pr_warn("APIC(%x) Package %u exceeds logical package map\n",
+                       apicid, pkg);
+               return -ENOSPC;
+       }
+       set_bit(new, logical_package_map);
+       pr_info("APIC(%x) Converting physical %u to logical package %u\n",
+               apicid, pkg, new);
+       physical_to_logical_pkg[pkg] = new;
+
+found:
+       cpu_data(cpu).logical_proc_id = physical_to_logical_pkg[pkg];
+       return 0;
+}
+
+/**
+ * topology_phys_to_logical_pkg - Map a physical package id to a logical
+ *
+ * Returns logical package id or -1 if not found
+ */
+int topology_phys_to_logical_pkg(unsigned int phys_pkg)
+{
+       if (phys_pkg >= max_physical_pkg_id)
+               return -1;
+       return physical_to_logical_pkg[phys_pkg];
+}
+EXPORT_SYMBOL(topology_phys_to_logical_pkg);
+
+static void __init smp_init_package_map(void)
+{
+       unsigned int ncpus, cpu;
+       size_t size;
+
+       /*
+        * Today neither Intel nor AMD support heterogenous systems. That
+        * might change in the future....
+        */
+       ncpus = boot_cpu_data.x86_max_cores * smp_num_siblings;
+       __max_logical_packages = DIV_ROUND_UP(nr_cpu_ids, ncpus);
+
+       /*
+        * Possibly larger than what we need as the number of apic ids per
+        * package can be smaller than the actual used apic ids.
+        */
+       max_physical_pkg_id = DIV_ROUND_UP(MAX_LOCAL_APIC, ncpus);
+       size = max_physical_pkg_id * sizeof(unsigned int);
+       physical_to_logical_pkg = kmalloc(size, GFP_KERNEL);
+       memset(physical_to_logical_pkg, 0xff, size);
+       size = BITS_TO_LONGS(max_physical_pkg_id) * sizeof(unsigned long);
+       physical_package_map = kzalloc(size, GFP_KERNEL);
+       size = BITS_TO_LONGS(__max_logical_packages) * sizeof(unsigned long);
+       logical_package_map = kzalloc(size, GFP_KERNEL);
+
+       pr_info("Max logical packages: %u\n", __max_logical_packages);
+
+       for_each_present_cpu(cpu) {
+               unsigned int apicid = apic->cpu_present_to_apicid(cpu);
+
+               if (apicid == BAD_APICID || !apic->apic_id_valid(apicid))
+                       continue;
+               if (!topology_update_package_map(apicid, cpu))
+                       continue;
+               pr_warn("CPU %u APICId %x disabled\n", cpu, apicid);
+               per_cpu(x86_bios_cpu_apicid, cpu) = BAD_APICID;
+               set_cpu_possible(cpu, false);
+               set_cpu_present(cpu, false);
+       }
+}
+
 void __init smp_store_boot_cpu_info(void)
 {
        int id = 0; /* CPU 0 */
@@ -258,6 +357,7 @@ void __init smp_store_boot_cpu_info(void)
 
        *c = boot_cpu_data;
        c->cpu_index = id;
+       smp_init_package_map();
 }
 
 /*