cpu: Register a generic CPU device on architectures that currently do not

frv, h8300, m68k, microblaze, openrisc, score, um and xtensa currently
do not register a CPU device.  Add the config option GENERIC_CPU_DEVICES
which causes a generic CPU device to be registered for each present CPU,
and make all these architectures select it.

Richard Weinberger <richard@nod.at> covered UML and suggested using
per_cpu.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig
index bbbf792..a685910 100644 (file)
--- a/arch/frv/Kconfig
+++ b/arch/frv/Kconfig
@@ -8,6 +8,7 @@ config FRV
        select HAVE_GENERIC_HARDIRQS
        select GENERIC_IRQ_SHOW
        select ARCH_HAVE_NMI_SAFE_CMPXCHG
+       select GENERIC_CPU_DEVICES
 
 config ZONE_DMA
        bool

diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
index d1f377f..56e890d 100644 (file)
--- a/arch/h8300/Kconfig
+++ b/arch/h8300/Kconfig
@@ -4,6 +4,7 @@ config H8300
        select HAVE_IDE
        select HAVE_GENERIC_HARDIRQS
        select GENERIC_IRQ_SHOW
+       select GENERIC_CPU_DEVICES
 
 config SYMBOL_PREFIX
        string

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 99c3636..ae413d4 100644 (file)
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -6,6 +6,7 @@ config M68K
        select HAVE_GENERIC_HARDIRQS
        select GENERIC_IRQ_SHOW
        select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS
+       select GENERIC_CPU_DEVICES
 
 config RWSEM_GENERIC_SPINLOCK
        bool

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index f0eead7..74f23a4 100644 (file)
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -18,6 +18,7 @@ config MICROBLAZE
        select GENERIC_IRQ_PROBE
        select GENERIC_IRQ_SHOW
        select GENERIC_PCI_IOMAP
+       select GENERIC_CPU_DEVICES
 
 config SWAP
        def_bool n

diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index 081a54f..bc428b5 100644 (file)
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -15,6 +15,7 @@ config OPENRISC
        select GENERIC_IRQ_PROBE
        select GENERIC_IRQ_SHOW
        select GENERIC_IOMAP
+       select GENERIC_CPU_DEVICES
 
 config MMU
        def_bool y

diff --git a/arch/score/Kconfig b/arch/score/Kconfig
index 3df65d3..4b28577 100644 (file)
--- a/arch/score/Kconfig
+++ b/arch/score/Kconfig
@@ -8,6 +8,7 @@ config SCORE
        select HAVE_MEMBLOCK
        select HAVE_MEMBLOCK_NODE_MAP
        select ARCH_DISCARD_MEMBLOCK
+       select GENERIC_CPU_DEVICES
 
 choice
        prompt "System type"

diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index a923483..b37ae70 100644 (file)
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -8,6 +8,7 @@ config UML
        default y
        select HAVE_GENERIC_HARDIRQS
        select GENERIC_IRQ_SHOW
+       select GENERIC_CPU_DEVICES
 
 config MMU
        bool

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index c346ccd..8a3f835 100644 (file)
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -9,6 +9,7 @@ config XTENSA
        select HAVE_IDE
        select HAVE_GENERIC_HARDIRQS
        select GENERIC_IRQ_SHOW
+       select GENERIC_CPU_DEVICES
        help
          Xtensa processors are 32-bit RISC machines designed by Tensilica
          primarily for embedded systems.  These processors are both

diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index e95c67e..fcbec8a 100644 (file)
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -172,6 +172,10 @@ config SYS_HYPERVISOR
        bool
        default n
 
+config GENERIC_CPU_DEVICES
+       bool
+       default n
+
 source "drivers/base/regmap/Kconfig"
 
 config DMA_SHARED_BUFFER

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index bba70d0..db87e78 100644 (file)
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -11,6 +11,7 @@
 #include <linux/device.h>
 #include <linux/node.h>
 #include <linux/gfp.h>
+#include <linux/percpu.h>
 
 #include "base.h"
 
@@ -275,11 +276,29 @@ bool cpu_is_hotpluggable(unsigned cpu)
 }
 EXPORT_SYMBOL_GPL(cpu_is_hotpluggable);
 
+#ifdef CONFIG_GENERIC_CPU_DEVICES
+static DEFINE_PER_CPU(struct cpu, cpu_devices);
+#endif
+
+static void __init cpu_dev_register_generic(void)
+{
+#ifdef CONFIG_GENERIC_CPU_DEVICES
+       int i;
+
+       for_each_possible_cpu(i) {
+               if (register_cpu(&per_cpu(cpu_devices, i), i))
+                       panic("Failed to register CPU device");
+       }
+#endif
+}
+
 void __init cpu_dev_init(void)
 {
        if (subsys_system_register(&cpu_subsys, cpu_root_attr_groups))
                panic("Failed to register CPU subsystem");
 
+       cpu_dev_register_generic();
+
 #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
        sched_create_sysfs_power_savings_entries(cpu_subsys.dev_root);
 #endif