readahead: remove several readahead macros
Remove VM_MAX_CACHE_HIT, MAX_RA_PAGES and MIN_RA_PAGES.
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index fbff8e4..291c4cc 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1106,8 +1106,6 @@
/* readahead.c */
#define VM_MAX_READAHEAD 128 /* kbytes */
#define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */
-#define VM_MAX_CACHE_HIT 256 /* max pages in a row in cache before
- * turning readahead off */
int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
pgoff_t offset, unsigned long nr_to_read);
diff --git a/mm/readahead.c b/mm/readahead.c
index fd588ffc..fc52f9f 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -22,16 +22,8 @@
}
EXPORT_SYMBOL(default_unplug_io_fn);
-/*
- * Convienent macros for min/max read-ahead pages.
- * Note that MAX_RA_PAGES is rounded down, while MIN_RA_PAGES is rounded up.
- * The latter is necessary for systems with large page size(i.e. 64k).
- */
-#define MAX_RA_PAGES (VM_MAX_READAHEAD*1024 / PAGE_CACHE_SIZE)
-#define MIN_RA_PAGES DIV_ROUND_UP(VM_MIN_READAHEAD*1024, PAGE_CACHE_SIZE)
-
struct backing_dev_info default_backing_dev_info = {
- .ra_pages = MAX_RA_PAGES,
+ .ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE,
.state = 0,
.capabilities = BDI_CAP_MAP_COPY,
.unplug_io_fn = default_unplug_io_fn,