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authorShaohua Li <shli@kernel.org>2013-02-23 01:34:35 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-24 02:50:17 +0100
commit9800339b5e0f0e24ab3dac349e0de80d2018832e (patch)
tree7f0cc5d46cbf881729ff3b2d97f425570674c95d /mm/util.c
parentmm: numa: cleanup flow of transhuge page migration (diff)
downloadlinux-9800339b5e0f0e24ab3dac349e0de80d2018832e.tar.xz
linux-9800339b5e0f0e24ab3dac349e0de80d2018832e.zip
mm: don't inline page_mapping()
According to akpm, this saves 1/2k text and makes things simple for the next patch. Numbers from Minchan: add/remove: 1/0 grow/shrink: 6/22 up/down: 92/-516 (-424) function old new delta page_mapping - 48 +48 do_task_stat 2292 2308 +16 page_remove_rmap 240 248 +8 load_elf_binary 4500 4508 +8 update_queue 532 536 +4 scsi_probe_and_add_lun 2892 2896 +4 lookup_fast 644 648 +4 vcs_read 1040 1036 -4 __ip_route_output_key 1904 1900 -4 ip_route_input_noref 2508 2500 -8 shmem_file_aio_read 784 772 -12 __isolate_lru_page 272 256 -16 shmem_replace_page 708 688 -20 mark_buffer_dirty 228 208 -20 __set_page_dirty_buffers 240 220 -20 __remove_mapping 276 256 -20 update_mmu_cache 500 476 -24 set_page_dirty_balance 92 68 -24 set_page_dirty 172 148 -24 page_evictable 88 64 -24 page_cache_pipe_buf_steal 248 224 -24 clear_page_dirty_for_io 340 316 -24 test_set_page_writeback 400 372 -28 test_clear_page_writeback 516 488 -28 invalidate_inode_page 156 128 -28 page_mkclean 432 400 -32 flush_dcache_page 360 328 -32 __set_page_dirty_nobuffers 324 280 -44 shrink_page_list 2412 2356 -56 Signed-off-by: Shaohua Li <shli@fusionio.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/util.c')
-rw-r--r--mm/util.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/mm/util.c b/mm/util.c
index 3704bf1bef94..16a73195a37b 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -5,6 +5,7 @@
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/security.h>
+#include <linux/swap.h>
#include <asm/uaccess.h>
#include "internal.h"
@@ -382,6 +383,21 @@ unsigned long vm_mmap(struct file *file, unsigned long addr,
}
EXPORT_SYMBOL(vm_mmap);
+struct address_space *page_mapping(struct page *page)
+{
+ struct address_space *mapping = page->mapping;
+
+ VM_BUG_ON(PageSlab(page));
+#ifdef CONFIG_SWAP
+ if (unlikely(PageSwapCache(page)))
+ mapping = &swapper_space;
+ else
+#endif
+ if ((unsigned long)mapping & PAGE_MAPPING_ANON)
+ mapping = NULL;
+ return mapping;
+}
+
/* Tracepoints definitions. */
EXPORT_TRACEPOINT_SYMBOL(kmalloc);
EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);