percpu: kill percpu_alloc() and friends

Impact: kill unused functions

percpu_alloc() and its friends never saw much action.  It was supposed
to replace the cpu-mask unaware __alloc_percpu() but it never happened
and in fact __percpu_alloc_mask() itself never really grew proper
up/down handling interface either (no exported interface for
populate/depopulate).

percpu allocation is about to go through major reimplementation and
there's no reason to carry this unused interface around.  Replace it
with __alloc_percpu() and free_percpu().

Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 22 insertions, 25 deletions

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 1fdaee93c04d..d99e24ae1811 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -82,46 +82,43 @@ struct percpu_data {
 
 #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
 
-extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask);
-extern void percpu_free(void *__pdata);
+/*
+ * Use this to get to a cpu's version of the per-cpu object
+ * dynamically allocated. Non-atomic access to the current CPU's
+ * version should probably be combined with get_cpu()/put_cpu().
+ */
+#define per_cpu_ptr(ptr, cpu)                                           \
+({                                                                      \
+        struct percpu_data *__p = __percpu_disguise(ptr);               \
+        (__typeof__(ptr))__p->ptrs[(cpu)];                              \
+})
+
+extern void *__alloc_percpu(size_t size, size_t align);
+extern void free_percpu(void *__pdata);
 
 #else /* CONFIG_SMP */
 
 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
 
-static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask)
+static inline void *__alloc_percpu(size_t size, size_t align)
 {
+        /*
+         * Can't easily make larger alignment work with kmalloc.  WARN
+         * on it.  Larger alignment should only be used for module
+         * percpu sections on SMP for which this path isn't used.
+         */
+        WARN_ON_ONCE(align > __alignof__(unsigned long long));
         return kzalloc(size, gfp);
 }
 
-static inline void percpu_free(void *__pdata)
+static inline void free_percpu(void *p)
 {
-        kfree(__pdata);
+        kfree(p);
 }
 
 #endif /* CONFIG_SMP */
 
-#define percpu_alloc_mask(size, gfp, mask) \
-        __percpu_alloc_mask((size), (gfp), &(mask))
-
-#define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map)
-
-/* (legacy) interface for use without CPU hotplug handling */
-
-#define __alloc_percpu(size, align)     percpu_alloc_mask((size), GFP_KERNEL, \
-                                                  cpu_possible_map)
 #define alloc_percpu(type)      (type *)__alloc_percpu(sizeof(type), \
                                                        __alignof__(type))
-#define free_percpu(ptr)        percpu_free((ptr))
-/*
- * Use this to get to a cpu's version of the per-cpu object dynamically
- * allocated. Non-atomic access to the current CPU's version should
- * probably be combined with get_cpu()/put_cpu().
- */
-#define per_cpu_ptr(ptr, cpu)                                           \
-({                                                                      \
-        struct percpu_data *__p = __percpu_disguise(ptr);               \
-        (__typeof__(ptr))__p->ptrs[(cpu)];                              \
-})
 
 #endif /* __LINUX_PERCPU_H */