percpu: don't implicitly include slab.h from percpu.h

percpu.h has always been including slab.h to get k[mz]alloc/free() for UP inline implementation. percpu.h being used by very low level headers including module.h and sched.h, this meant that a lot files unintentionally got slab.h inclusion. Lee Schermerhorn was trying to make topology.h use percpu.h and got bitten by this implicit inclusion. The right thing to do is break this ultimately unnecessary dependency. The previous patch added explicit inclusion of either gfp.h or slab.h to the source files using them. This patch updates percpu.h such that slab.h is no longer included from percpu.h. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

percpu: don't implicitly include slab.h from percpu.h
percpu.h has always been including slab.h to get k[mz]alloc/free() for UP inline implementation. percpu.h being used by very low level headers including module.h and sched.h, this meant that a lot files unintentionally got slab.h inclusion. Lee Schermerhorn was trying to make topology.h use percpu.h and got bitten by this implicit inclusion. The right thing to do is break this ultimately unnecessary dependency. The previous patch added explicit inclusion of either gfp.h or slab.h to the source files using them. This patch updates percpu.h such that slab.h is no longer included from percpu.h. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Tejun Heo
1 parent ea5a9f0c34
Showing 3 changed files with 40 additions and 26 deletions Side-by-side Diff
include/linux/percpu.h
mm/Makefile
mm/percpu_up.c
@@ -2,10 +2,10 @@
 #define __LINUX_PERCPU_H
  
 #include <linux/preempt.h>
-#include <linux/slab.h> /* For kmalloc() */
 #include <linux/smp.h>
 #include <linux/cpumask.h>
 #include <linux/pfn.h>
+#include <linux/init.h>
  
 #include <asm/percpu.h>
  
@@ -135,9 +135,6 @@
 #define per_cpu_ptr(ptr, cpu)	SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
  
 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
-extern void __percpu *__alloc_percpu(size_t size, size_t align);
-extern void free_percpu(void __percpu *__pdata);
-extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
  
 #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
 extern void __init setup_per_cpu_areas(void);
@@ -147,27 +144,6 @@
  
 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
  
-static inline void __percpu *__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 > SMP_CACHE_BYTES);
-	return kzalloc(size, GFP_KERNEL);
-}
-
-static inline void free_percpu(void __percpu *p)
-{
-	kfree(p);
-}
-
-static inline phys_addr_t per_cpu_ptr_to_phys(void *addr)
-{
-	return __pa(addr);
-}
-
 static inline void __init setup_per_cpu_areas(void) { }
  
 static inline void *pcpu_lpage_remapped(void *kaddr)
@@ -176,6 +152,10 @@
 }
  
 #endif /* CONFIG_SMP */
+
+extern void __percpu *__alloc_percpu(size_t size, size_t align);
+extern void free_percpu(void __percpu *__pdata);
+extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
  
 #define alloc_percpu(type)	\
 	(typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
@@ -33,7 +33,11 @@
 obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
 obj-$(CONFIG_FS_XIP) += filemap_xip.o
 obj-$(CONFIG_MIGRATION) += migrate.o
-obj-$(CONFIG_SMP) += percpu.o
+ifdef CONFIG_SMP
+obj-y += percpu.o
+else
+obj-y += percpu_up.o
+endif
 obj-$(CONFIG_QUICKLIST) += quicklist.o
 obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o
 obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o
+/*
+ * mm/percpu_up.c - dummy percpu memory allocator implementation for UP
+ */
+
+#include <linux/module.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+
+void __percpu *__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 > SMP_CACHE_BYTES);
+	return kzalloc(size, GFP_KERNEL);
+}
+EXPORT_SYMBOL_GPL(__alloc_percpu);
+
+void free_percpu(void __percpu *p)
+{
+	kfree(p);
+}
+EXPORT_SYMBOL_GPL(free_percpu);
+
+phys_addr_t per_cpu_ptr_to_phys(void *addr)
+{
+	return __pa(addr);
+}
...	...	@@ -2,10 +2,10 @@
2	2	#define __LINUX_PERCPU_H
3	3
4	4	#include <linux/preempt.h>
5		-#include <linux/slab.h> /* For kmalloc() */
6	5	#include <linux/smp.h>
7	6	#include <linux/cpumask.h>
8	7	#include <linux/pfn.h>
	8	+#include <linux/init.h>
9	9
10	10	#include <asm/percpu.h>
11	11
...	...	@@ -135,9 +135,6 @@
135	135	#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
136	136
137	137	extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
138		-extern void __percpu *__alloc_percpu(size_t size, size_t align);
139		-extern void free_percpu(void __percpu *__pdata);
140		-extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
141	138
142	139	#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
143	140	extern void __init setup_per_cpu_areas(void);
...	...	@@ -147,27 +144,6 @@
147	144
148	145	#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
149	146
150		-static inline void __percpu *__alloc_percpu(size_t size, size_t align)
151		-{
152		- /*
153		- * Can't easily make larger alignment work with kmalloc. WARN
154		- * on it. Larger alignment should only be used for module
155		- * percpu sections on SMP for which this path isn't used.
156		- */
157		- WARN_ON_ONCE(align > SMP_CACHE_BYTES);
158		- return kzalloc(size, GFP_KERNEL);
159		-}
160		-
161		-static inline void free_percpu(void __percpu *p)
162		-{
163		- kfree(p);
164		-}
165		-
166		-static inline phys_addr_t per_cpu_ptr_to_phys(void *addr)
167		-{
168		- return __pa(addr);
169		-}
170		-
171	147	static inline void __init setup_per_cpu_areas(void) { }
172	148
173	149	static inline void pcpu_lpage_remapped(void kaddr)
...	...	@@ -176,6 +152,10 @@
176	152	}
177	153
178	154	#endif /* CONFIG_SMP */
	155	+
	156	+extern void __percpu *__alloc_percpu(size_t size, size_t align);
	157	+extern void free_percpu(void __percpu *__pdata);
	158	+extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
179	159
180	160	#define alloc_percpu(type) \
181	161	(typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
...	...	@@ -33,7 +33,11 @@
33	33	obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
34	34	obj-$(CONFIG_FS_XIP) += filemap_xip.o
35	35	obj-$(CONFIG_MIGRATION) += migrate.o
36		-obj-$(CONFIG_SMP) += percpu.o
	36	+ifdef CONFIG_SMP
	37	+obj-y += percpu.o
	38	+else
	39	+obj-y += percpu_up.o
	40	+endif
37	41	obj-$(CONFIG_QUICKLIST) += quicklist.o
38	42	obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o
39	43	obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o
	1	+/*
	2	+ * mm/percpu_up.c - dummy percpu memory allocator implementation for UP
	3	+ */
	4	+
	5	+#include <linux/module.h>
	6	+#include <linux/percpu.h>
	7	+#include <linux/slab.h>
	8	+
	9	+void __percpu *__alloc_percpu(size_t size, size_t align)
	10	+{
	11	+ /*
	12	+ * Can't easily make larger alignment work with kmalloc. WARN
	13	+ * on it. Larger alignment should only be used for module
	14	+ * percpu sections on SMP for which this path isn't used.
	15	+ */
	16	+ WARN_ON_ONCE(align > SMP_CACHE_BYTES);
	17	+ return kzalloc(size, GFP_KERNEL);
	18	+}
	19	+EXPORT_SYMBOL_GPL(__alloc_percpu);
	20	+
	21	+void free_percpu(void __percpu *p)
	22	+{
	23	+ kfree(p);
	24	+}
	25	+EXPORT_SYMBOL_GPL(free_percpu);
	26	+
	27	+phys_addr_t per_cpu_ptr_to_phys(void *addr)
	28	+{
	29	+ return __pa(addr);
	30	+}