File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/kernel/up.c b/kernel/up.c
new file mode 100644
index 0000000..1760bf3
--- /dev/null
+++ b/kernel/up.c
@@ -0,0 +1,84 @@
+/*
+ * Uniprocessor-only support functions. The counterpart to kernel/smp.c
+ */
+
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/smp.h>
+
+int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
+ int wait)
+{
+ unsigned long flags;
+
+ WARN_ON(cpu != 0);
+
+ local_irq_save(flags);
+ func(info);
+ local_irq_restore(flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(smp_call_function_single);
+
+int smp_call_function_single_async(int cpu, struct call_single_data *csd)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ csd->func(csd->info);
+ local_irq_restore(flags);
+ return 0;
+}
+EXPORT_SYMBOL(smp_call_function_single_async);
+
+int on_each_cpu(smp_call_func_t func, void *info, int wait)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ func(info);
+ local_irq_restore(flags);
+ return 0;
+}
+EXPORT_SYMBOL(on_each_cpu);
+
+/*
+ * Note we still need to test the mask even for UP
+ * because we actually can get an empty mask from
+ * code that on SMP might call us without the local
+ * CPU in the mask.
+ */
+void on_each_cpu_mask(const struct cpumask *mask,
+ smp_call_func_t func, void *info, bool wait)
+{
+ unsigned long flags;
+
+ if (cpumask_test_cpu(0, mask)) {
+ local_irq_save(flags);
+ func(info);
+ local_irq_restore(flags);
+ }
+}
+EXPORT_SYMBOL(on_each_cpu_mask);
+
+/*
+ * Preemption is disabled here to make sure the cond_func is called under the
+ * same condtions in UP and SMP.
+ */
+void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
+ smp_call_func_t func, void *info, bool wait,
+ gfp_t gfp_flags)
+{
+ unsigned long flags;
+
+ preempt_disable();
+ if (cond_func(0, info)) {
+ local_irq_save(flags);
+ func(info);
+ local_irq_restore(flags);
+ }
+ preempt_enable();
+}
+EXPORT_SYMBOL(on_each_cpu_cond);