x86/topology: Avoid wasting 128k for package id array

[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kernel / smpboot.c

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 5f59e6bee123ffb324ec12a02d1921a7029ddc96..da5e162636fd636226f854e628e49bbf5d403dde 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -101,9 +101,6 @@ 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 int max_physical_pkg_id __read_mostly;
 unsigned int __max_logical_packages __read_mostly;
 EXPORT_SYMBOL(__max_logical_packages);
 static unsigned int logical_packages __read_mostly;
@@ -280,6 +277,25 @@ static void notrace start_secondary(void *unused)
        cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
 
+/**
+ * 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)
+{
+       int cpu;
+
+       for_each_possible_cpu(cpu) {
+               struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+               if (c->initialized && c->phys_proc_id == phys_pkg)
+                       return c->logical_proc_id;
+       }
+       return -1;
+}
+EXPORT_SYMBOL(topology_phys_to_logical_pkg);
+
 /**
  * topology_update_package_map - Update the physical to logical package map
  * @pkg:       The physical package id as retrieved via CPUID
@@ -287,17 +303,11 @@ static void notrace start_secondary(void *unused)
  */
 int topology_update_package_map(unsigned int pkg, unsigned int cpu)
 {
-       unsigned int new;
-
-       /* Called from early boot ? */
-       if (!physical_package_map)
-               return 0;
-
-       if (pkg >= max_physical_pkg_id)
-               return -EINVAL;
+       int new;
 
-       /* Set the logical package id */
-       if (test_and_set_bit(pkg, physical_package_map))
+       /* Already available somewhere? */
+       new = topology_phys_to_logical_pkg(pkg);
+       if (new >= 0)
                goto found;
 
        if (logical_packages >= __max_logical_packages) {
@@ -311,30 +321,14 @@ int topology_update_package_map(unsigned int pkg, unsigned int cpu)
                pr_info("CPU %u Converting physical %u to logical package %u\n",
                        cpu, pkg, new);
        }
-       physical_to_logical_pkg[pkg] = new;
-
 found:
-       cpu_data(cpu).logical_proc_id = physical_to_logical_pkg[pkg];
+       cpu_data(cpu).logical_proc_id = new;
        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(struct cpuinfo_x86 *c, unsigned int cpu)
 {
        unsigned int ncpus;
-       size_t size;
 
        /*
         * Today neither Intel nor AMD support heterogenous systems. That
@@ -365,19 +359,6 @@ static void __init smp_init_package_map(struct cpuinfo_x86 *c, unsigned int cpu)
        }
 
        __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
-       logical_packages = 0;
-
-       /*
-        * 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);
-
        pr_info("Max logical packages: %u\n", __max_logical_packages);
 
        topology_update_package_map(c->phys_proc_id, cpu);
@@ -391,6 +372,7 @@ void __init smp_store_boot_cpu_info(void)
        *c = boot_cpu_data;
        c->cpu_index = id;
        smp_init_package_map(c, id);
+       c->initialized = true;
 }
 
 /*
@@ -401,13 +383,16 @@ void smp_store_cpu_info(int id)
 {
        struct cpuinfo_x86 *c = &cpu_data(id);
 
-       *c = boot_cpu_data;
+       /* Copy boot_cpu_data only on the first bringup */
+       if (!c->initialized)
+               *c = boot_cpu_data;
        c->cpu_index = id;
        /*
         * During boot time, CPU0 has this setup already. Save the info when
         * bringing up AP or offlined CPU0.
         */
        identify_secondary_cpu(c);
+       c->initialized = true;
 }
 
 static bool