[PATCH] per-cpu areas

This is the Richard Henderson-approved, cleaner, brighter per-cpu patch.

1 files changed, 25 insertions, 0 deletions

diff --git a/init/main.c b/init/main.c
index 9a810361e27a..524abe909c64 100644
--- a/init/main.c
+++ b/init/main.c
@@ -270,8 +270,32 @@ static void __init smp_init(void)
 #define smp_init()	do { } while (0)
 #endif
 
+static inline void setup_per_cpu_areas(void)
+{
+}
 #else
 
+#ifndef __HAVE_ARCH_PER_CPU
+unsigned long __per_cpu_offset[NR_CPUS];
+
+static void __init setup_per_cpu_areas(void)
+{
+	unsigned long size, i;
+	char *ptr;
+	/* Created by linker magic */
+	extern char __per_cpu_start[], __per_cpu_end[];
+
+	/* Copy section for each CPU (we discard the original) */
+	size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
+	ptr = alloc_bootmem(size * NR_CPUS);
+
+	for (i = 0; i < NR_CPUS; i++, ptr += size) {
+		__per_cpu_offset[i] = ptr - __per_cpu_start;
+		memcpy(ptr, __per_cpu_start, size);
+	}
+}
+#endif /* !__HAVE_ARCH_PER_CPU */
+
 /* Called by boot processor to activate the rest. */
 static void __init smp_init(void)
 {
@@ -314,6 +338,7 @@ asmlinkage void __init start_kernel(void)
 	lock_kernel();
 	printk(linux_banner);
 	setup_arch(&command_line);
+	setup_per_cpu_areas();
 	printk("Kernel command line: %s\n", saved_command_line);
 	parse_options(command_line);
 	trap_init();