1 files changed, 28 insertions, 0 deletions

diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c
index dfdee6a47359..df34ceae0c67 100644
--- a/mm/allocpercpu.c
+++ b/mm/allocpercpu.c
@@ -5,6 +5,8 @@
  */
 #include <linux/mm.h>
 #include <linux/module.h>
+#include <linux/bootmem.h>
+#include <asm/sections.h>
 
 #ifndef cache_line_size
 #define cache_line_size()       L1_CACHE_BYTES
@@ -147,3 +149,29 @@ void free_percpu(void *__pdata)
         kfree(__percpu_disguise(__pdata));
 }
 EXPORT_SYMBOL_GPL(free_percpu);
+
+/*
+ * Generic percpu area setup.
+ */
+#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
+unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
+
+EXPORT_SYMBOL(__per_cpu_offset);
+
+void __init setup_per_cpu_areas(void)
+{
+        unsigned long size, i;
+        char *ptr;
+        unsigned long nr_possible_cpus = num_possible_cpus();
+
+        /* Copy section for each CPU (we discard the original) */
+        size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
+        ptr = alloc_bootmem_pages(size * nr_possible_cpus);
+
+        for_each_possible_cpu(i) {
+                __per_cpu_offset[i] = ptr - __per_cpu_start;
+                memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
+                ptr += size;
+        }
+}
+#endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */