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>
joolstorrentecalo · Jan 11, 2012 · 9f13a1f · 9f13a1f
1 parent 024f784
commit 9f13a1f
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Showing 10 changed files with 31 additions and 0 deletions.
diff --git 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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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