Re: [PATCH 3/6] x86: simplify _acpi_map_lsapic()

On Saturday, August 31, 2013 06:15:58 PM Hanjun Guo wrote:

From: Jiang Liu jiang.liu@huawei.com

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

---

arch/x86/include/asm/mpspec.h | 2 +- arch/x86/kernel/acpi/boot.c | 48 +++++++++++++---------------------------- arch/x86/kernel/apic/apic.c | 8 ++++--- 3 files changed, 21 insertions(+), 37 deletions(-)

diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h index 626cf70..3142a94 100644 --- 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 3e186d1..ca73370 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -195,24 +195,31 @@ 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-1)) { printk(KERN_INFO PREFIX "skipped apicid that is too big\n");

• return;
  

• return -1;
  

  }

if (!enabled) { ++disabled_cpus;

• return;
  

• return -1;
  

  }

If this returned -EINVAL instead of just -1, ->

if (boot_cpu_physical_apicid != -1U) ver = apic_version[boot_cpu_physical_apicid];

• generic_processor_info(id, ver);

• return generic_processor_info(id, ver);

-> and this too (on errors), -->

} static int __init @@ -622,44 +629,19 @@ 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)) {

• cpu = acpi_register_lapic(physid, ACPI_MADT_ENABLED);
• if (cpu == -1) { printk ("Unable to map lapic to logical cpu number\n");

• retval = -EINVAL;
  

• goto free_new_map;
  

• return -EINVAL;
  

  }

--> then this could be

if (cpu < 0) { ... 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 eca89c5..87128778 100644 --- 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 -1;
  

  }

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 -1;
  

  }

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)