[PATCH v4 11/35] percpu_counter.h: move declarations to percpu_counter_types.h

[Max Kellermann <max.kellermann@ionos.com>]

By providing declarations in a lean header, we can reduce header
dependencies.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 include/linux/backing-dev-defs.h     |  2 +-
 include/linux/flex_proportions.h     |  2 +-
 include/linux/ipc_namespace.h        |  2 +-
 include/linux/mm_types.h             |  3 ++-
 include/linux/percpu_counter.h       | 17 +------------
 include/linux/percpu_counter_types.h | 37 ++++++++++++++++++++++++++++
 include/linux/sched/user.h           |  2 +-
 include/linux/shmem_fs.h             |  2 +-
 kernel/user.c                        |  1 +
 lib/flex_proportions.c               |  1 +
 10 files changed, 47 insertions(+), 22 deletions(-)
 create mode 100644 include/linux/percpu_counter_types.h

diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index 68fdec049456..720a88bb3513 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -6,7 +6,7 @@
 #include <linux/radix-tree.h>
 #include <linux/rbtree_types.h>
 #include <linux/spinlock_types.h>
-#include <linux/percpu_counter.h>
+#include <linux/percpu_counter_types.h>
 #include <linux/percpu-refcount.h>
 #include <linux/flex_proportions.h>
 #include <linux/timer_types.h>
diff --git a/include/linux/flex_proportions.h b/include/linux/flex_proportions.h
index 35204b64addf..df9017a61046 100644
--- a/include/linux/flex_proportions.h
+++ b/include/linux/flex_proportions.h
@@ -8,7 +8,7 @@
 #ifndef _LINUX_FLEX_PROPORTIONS_H
 #define _LINUX_FLEX_PROPORTIONS_H
 
-#include <linux/percpu_counter.h>
+#include <linux/percpu_counter_types.h>
 #include <linux/spinlock_types.h>
 #include <linux/seqlock_types.h>
 #include <linux/gfp_types.h>
diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h
index a0011b6cd5d1..7c758ab565fe 100644
--- a/include/linux/ipc_namespace.h
+++ b/include/linux/ipc_namespace.h
@@ -11,7 +11,7 @@
 #include <linux/refcount.h>
 #include <linux/rhashtable-types.h>
 #include <linux/sysctl.h>
-#include <linux/percpu_counter.h>
+#include <linux/percpu_counter_types.h>
 
 struct user_namespace;
 
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 54caee378e77..a88219770c82 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -19,7 +19,8 @@
 #include <linux/page-flags-layout.h>
 #include <linux/workqueue_types.h>
 #include <linux/seqlock_types.h>
-#include <linux/percpu_counter.h>
+#include <linux/percpu_counter_types.h>
+#include <linux/percpu.h>
 
 #include <asm/mmu.h>
 
diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index 8d45785b3448..bec5e7cdd476 100644
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -7,26 +7,15 @@
  * WARNING: these things are HUGE.  4 kbytes per counter on 32-way P4.
  */
 
-#include <linux/spinlock_types.h>
-#include <linux/list.h>
+#include <linux/percpu_counter_types.h>
 #include <linux/threads.h>
 #include <linux/percpu.h>
-#include <linux/types.h>
 
 /* percpu_counter batch for local add or sub */
 #define PERCPU_COUNTER_LOCAL_BATCH	INT_MAX
 
 #ifdef CONFIG_SMP
 
-struct percpu_counter {
-	raw_spinlock_t lock;
-	s64 count;
-#ifdef CONFIG_HOTPLUG_CPU
-	struct list_head list;	/* All percpu_counters are on a list */
-#endif
-	s32 __percpu *counters;
-};
-
 extern int percpu_counter_batch;
 
 int __percpu_counter_init_many(struct percpu_counter *fbc, s64 amount,
@@ -131,10 +120,6 @@ static inline bool percpu_counter_initialized(struct percpu_counter *fbc)
 
 #else /* !CONFIG_SMP */
 
-struct percpu_counter {
-	s64 count;
-};
-
 static inline int percpu_counter_init_many(struct percpu_counter *fbc,
 					   s64 amount, gfp_t gfp,
 					   u32 nr_counters)
diff --git a/include/linux/percpu_counter_types.h b/include/linux/percpu_counter_types.h
new file mode 100644
index 000000000000..faccd9869a5a
--- /dev/null
+++ b/include/linux/percpu_counter_types.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_PERCPU_COUNTER_TYPES_H
+#define _LINUX_PERCPU_COUNTER_TYPES_H
+/*
+ * A simple "approximate counter" for use in ext2 and ext3 superblocks.
+ *
+ * WARNING: these things are HUGE.  4 kbytes per counter on 32-way P4.
+ */
+
+#include <linux/types.h>
+
+#ifdef CONFIG_SMP
+
+#include <linux/spinlock_types.h>
+
+#ifdef CONFIG_HOTPLUG_CPU
+#include <linux/list.h>
+#endif
+
+struct percpu_counter {
+	raw_spinlock_t lock;
+	s64 count;
+#ifdef CONFIG_HOTPLUG_CPU
+	struct list_head list;	/* All percpu_counters are on a list */
+#endif
+	s32 __percpu *counters;
+};
+
+#else /* !CONFIG_SMP */
+
+struct percpu_counter {
+	s64 count;
+};
+
+#endif	/* CONFIG_SMP */
+
+#endif /* _LINUX_PERCPU_COUNTER_TYPES_H */
diff --git a/include/linux/sched/user.h b/include/linux/sched/user.h
index 671ecee08d23..913da0aba05c 100644
--- a/include/linux/sched/user.h
+++ b/include/linux/sched/user.h
@@ -4,7 +4,7 @@
 
 #include <linux/uidgid_types.h>
 #include <linux/atomic.h>
-#include <linux/percpu_counter.h>
+#include <linux/percpu_counter_types.h>
 #include <linux/refcount.h>
 #include <linux/ratelimit_types.h>
 
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 2caa6b86106a..1d7e56eab60f 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -6,7 +6,7 @@
 #include <linux/swap.h>
 #include <linux/mempolicy.h>
 #include <linux/pagemap.h>
-#include <linux/percpu_counter.h>
+#include <linux/percpu_counter_types.h>
 #include <linux/xattr.h>
 #include <linux/fs_parser.h>
 #include <linux/userfaultfd_k.h>
diff --git a/kernel/user.c b/kernel/user.c
index 28da71ea1e74..6c8b818419f8 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -22,6 +22,7 @@
 #include <linux/proc_ns.h>
 #include <linux/ratelimit.h>
 #include <linux/uidgid.h>
+#include <linux/percpu_counter.h>
 
 #if IS_ENABLED(CONFIG_BINFMT_MISC)
 struct binfmt_misc init_binfmt_misc = {
diff --git a/lib/flex_proportions.c b/lib/flex_proportions.c
index 7749a48428e5..1d5e1e0bdbbe 100644
--- a/lib/flex_proportions.c
+++ b/lib/flex_proportions.c
@@ -36,6 +36,7 @@
 #include <linux/flex_proportions.h>
 #include <linux/log2.h>
 #include <linux/math64.h>
+#include <linux/percpu_counter.h>
 #include <linux/seqlock.h>
 
 int fprop_global_init(struct fprop_global *p, gfp_t gfp)
-- 
2.39.2