[patch 204/262] include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h

Andrew Morton
2021-11-05T20:45:30Z

From: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Subject: include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h

nr_free_buffer_pages could be exposed through mm.h instead of swap.h. The
advantage of this change is that it can reduce the obsolete includes. For
example, net/ipv4/tcp.c wouldn't need swap.h any more since it has already
included mm.h. Similarly, after checking all the other files, it comes
that tcp.c, udp.c meter.c ,... follow the same rule, so these files can
have swap.h removed too.

Moreover, after preprocessing all the files that use nr_free_buffer_pages,
it turns out that those files have already included mm.h.Thus, we can move
nr_free_buffer_pages from swap.h to mm.h safely. This change will not
affect the compilation of other files.

Link: https://lkml.kernel.org/r/20210912133640.1624-1-liumh1@shanghaitech.edu.cn
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
CC: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

drivers/mmc/core/mmc_test.c | 1 -
include/linux/mm.h | 2 ++
include/linux/swap.h | 1 -
net/ipv4/tcp.c | 1 -
net/ipv4/udp.c | 1 -
net/netfilter/ipvs/ip_vs_ctl.c | 1 -
net/openvswitch/meter.c | 1 -
net/sctp/protocol.c | 1 -
8 files changed, 2 insertions(+), 7 deletions(-)

--- a/drivers/mmc/core/mmc_test.c~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/drivers/mmc/core/mmc_test.c
@@ -10,7 +10,6 @@
#include <linux/slab.h>

#include <linux/scatterlist.h>
-#include <linux/swap.h> /* For nr_free_buffer_pages() */
#include <linux/list.h>

#include <linux/debugfs.h>
--- a/include/linux/mm.h~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/include/linux/mm.h
@@ -875,6 +875,8 @@ void put_pages_list(struct list_head *pa
void split_page(struct page *page, unsigned int order);
void copy_huge_page(struct page *dst, struct page *src);

+unsigned long nr_free_buffer_pages(void);
+
/*
* Compound pages have a destructor function. Provide a
* prototype for that function and accessor functions.
--- a/include/linux/swap.h~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/include/linux/swap.h
@@ -335,7 +335,6 @@ void workingset_update_node(struct xa_no

/* linux/mm/page_alloc.c */
extern unsigned long totalreserve_pages;
-extern unsigned long nr_free_buffer_pages(void);

/* Definition of global_zone_page_state not available yet */
#define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
--- a/net/ipv4/tcp.c~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/net/ipv4/tcp.c
@@ -260,7 +260,6 @@
#include <linux/random.h>
#include <linux/memblock.h>
#include <linux/highmem.h>
-#include <linux/swap.h>
#include <linux/cache.h>
#include <linux/err.h>
#include <linux/time.h>
--- a/net/ipv4/udp.c~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/net/ipv4/udp.c
@@ -78,7 +78,6 @@
#include <asm/ioctls.h>
#include <linux/memblock.h>
#include <linux/highmem.h>
-#include <linux/swap.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/module.h>
--- a/net/netfilter/ipvs/ip_vs_ctl.c~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/net/netfilter/ipvs/ip_vs_ctl.c
@@ -24,7 +24,6 @@
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/workqueue.h>
-#include <linux/swap.h>
#include <linux/seq_file.h>
#include <linux/slab.h>

--- a/net/openvswitch/meter.c~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/net/openvswitch/meter.c
@@ -12,7 +12,6 @@
#include <linux/openvswitch.h>
#include <linux/netlink.h>
#include <linux/rculist.h>
-#include <linux/swap.h>

#include <net/netlink.h>
#include <net/genetlink.h>
--- a/net/sctp/protocol.c~include-linux-mmh-move-nr_free_buffer_pages-from-swaph-to-mmh
+++ a/net/sctp/protocol.c
@@ -33,7 +33,6 @@
#include <linux/seq_file.h>
#include <linux/memblock.h>
#include <linux/highmem.h>
-#include <linux/swap.h>
#include <linux/slab.h>
#include <net/net_namespace.h>
#include <net/protocol.h>
_