flusher: Fix PF_FROZEN race

[safe/jmp/linux-2.6] / mm / allocpercpu.c

diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c
index 1882923..df34cea 100644 (file)
--- 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
@@ -31,7 +33,7 @@ static void percpu_depopulate(void *__pdata, int cpu)
  * @__pdata: per-cpu data to depopulate
  * @mask: depopulate per-cpu data for cpu's selected through mask bits
  */
-static void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask)
+static void __percpu_depopulate_mask(void *__pdata, const cpumask_t *mask)
 {
        int cpu;
        for_each_cpu_mask_nr(cpu, *mask)
@@ -143,7 +145,33 @@ void free_percpu(void *__pdata)
 {
        if (unlikely(!__pdata))
                return;
-       __percpu_depopulate_mask(__pdata, &cpu_possible_map);
+       __percpu_depopulate_mask(__pdata, cpu_possible_mask);
        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 */