x86 / ACPI: simplify _acpi_map_lsapic()

In acpi_register_lapic(), it will generates a new logical cpu
number and maps to the local APIC id, this logical cpu number
can be returned to simplify _acpi_map_lsapic() implementation.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
index 626cf70..3142a94 100644 (file)
--- a/arch/x86/include/asm/mpspec.h
+++ b/arch/x86/include/asm/mpspec.h
@@ -94,7 +94,7 @@ static inline void early_reserve_e820_mpc_new(void) { }
 #define default_get_smp_config x86_init_uint_noop
 #endif
 
-void generic_processor_info(int apicid, int version);
+int generic_processor_info(int apicid, int version);
 #ifdef CONFIG_ACPI
 extern void mp_register_ioapic(int id, u32 address, u32 gsi_base);
 extern void mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger,

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index f6dbb2f..1f7c074 100644 (file)
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -189,24 +189,31 @@ static int __init acpi_parse_madt(struct acpi_table_header *table)
        return 0;
 }
 
-static void acpi_register_lapic(int id, u8 enabled)
+/**
+ * acpi_register_lapic - register a local apic and generates a logic cpu number
+ * @id: local apic id to register
+ * @enabled: this cpu is enabled or not
+ *
+ * Returns the logic cpu number which maps to the local apic
+ */
+static int acpi_register_lapic(int id, u8 enabled)
 {
        unsigned int ver = 0;
 
        if (id >= MAX_LOCAL_APIC) {
                printk(KERN_INFO PREFIX "skipped apicid that is too big\n");
-               return;
+               return -EINVAL;
        }
 
        if (!enabled) {
                ++disabled_cpus;
-               return;
+               return -EINVAL;
        }
 
        if (boot_cpu_physical_apicid != -1U)
                ver = apic_version[boot_cpu_physical_apicid];
 
-       generic_processor_info(id, ver);
+       return generic_processor_info(id, ver);
 }
 
 static int __init
@@ -616,44 +623,19 @@ static void acpi_map_cpu2node(acpi_handle handle, int cpu, int physid)
 
 static int _acpi_map_lsapic(acpi_handle handle, int physid, int *pcpu)
 {
-       cpumask_var_t tmp_map, new_map;
        int cpu;
-       int retval = -ENOMEM;
-
-       if (!alloc_cpumask_var(&tmp_map, GFP_KERNEL))
-               goto out;
 
-       if (!alloc_cpumask_var(&new_map, GFP_KERNEL))
-               goto free_tmp_map;
-
-       cpumask_copy(tmp_map, cpu_present_mask);
-       acpi_register_lapic(physid, ACPI_MADT_ENABLED);
-
-       /*
-        * If acpi_register_lapic successfully generates a new logical cpu
-        * number, then the following will get us exactly what was mapped
-        */
-       cpumask_andnot(new_map, cpu_present_mask, tmp_map);
-       if (cpumask_empty(new_map)) {
-               printk ("Unable to map lapic to logical cpu number\n");
-               retval = -EINVAL;
-               goto free_new_map;
+       cpu = acpi_register_lapic(physid, ACPI_MADT_ENABLED);
+       if (cpu < 0) {
+               pr_info(PREFIX "Unable to map lapic to logical cpu number\n");
+               return cpu;
        }
 
        acpi_processor_set_pdc(handle);
-
-       cpu = cpumask_first(new_map);
        acpi_map_cpu2node(handle, cpu, physid);
 
        *pcpu = cpu;
-       retval = 0;
-
-free_new_map:
-       free_cpumask_var(new_map);
-free_tmp_map:
-       free_cpumask_var(tmp_map);
-out:
-       return retval;
+       return 0;
 }
 
 /* wrapper to silence section mismatch warning */

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index a7eb82d..ed165d6 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2107,7 +2107,7 @@ void disconnect_bsp_APIC(int virt_wire_setup)
        apic_write(APIC_LVT1, value);
 }
 
-void generic_processor_info(int apicid, int version)
+int generic_processor_info(int apicid, int version)
 {
        int cpu, max = nr_cpu_ids;
        bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
@@ -2127,7 +2127,7 @@ void generic_processor_info(int apicid, int version)
                        "  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
 
                disabled_cpus++;
-               return;
+               return -ENODEV;
        }
 
        if (num_processors >= nr_cpu_ids) {
@@ -2138,7 +2138,7 @@ void generic_processor_info(int apicid, int version)
                        "  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
 
                disabled_cpus++;
-               return;
+               return -EINVAL;
        }
 
        num_processors++;
@@ -2183,6 +2183,8 @@ void generic_processor_info(int apicid, int version)
 #endif
        set_cpu_possible(cpu, true);
        set_cpu_present(cpu, true);
+
+       return cpu;
 }
 
 int hard_smp_processor_id(void)