[PATCH 7/9] readahead: remove unused do_page_cache_readahead()

Fengguang Wu
2007-12-22T01:34:00Z

[-- Attachment #1: readahead-remove-do_page_cache_readahead.patch --]
[-- Type: text/plain, Size: 1799 bytes --]

Remove do_page_cache_readahead().
Its last user, mmap read-around, has been changed to call ra_submit().

Also, the no-readahead-if-congested logic is not appropriate here.
Raw 1-page reads can only makes things painfully slower, and
users are pretty sensitive about the slow loading of executables.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
---
include/linux/mm.h | 2 --
mm/readahead.c | 16 ----------------
2 files changed, 18 deletions(-)

--- linux-2.6.24-rc5-mm1.orig/include/linux/mm.h
+++ linux-2.6.24-rc5-mm1/include/linux/mm.h
@@ -1084,8 +1084,6 @@ int write_one_page(struct page *page, in
#define VM_MAX_READAHEAD 128 /* kbytes */
#define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */

-int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
- pgoff_t offset, unsigned long nr_to_read);
int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
pgoff_t offset, unsigned long nr_to_read);

--- linux-2.6.24-rc5-mm1.orig/mm/readahead.c
+++ linux-2.6.24-rc5-mm1/mm/readahead.c
@@ -208,22 +208,6 @@ int force_page_cache_readahead(struct ad
}

/*
- * This version skips the IO if the queue is read-congested, and will tell the
- * block layer to abandon the readahead if request allocation would block.
- *
- * force_page_cache_readahead() will ignore queue congestion and will block on
- * request queues.
- */
-int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
- pgoff_t offset, unsigned long nr_to_read)
-{
- if (bdi_read_congested(mapping->backing_dev_info))
- return -1;
-
- return __do_page_cache_readahead(mapping, filp, offset, nr_to_read, 0);
-}
-
-/*
* Given a desired number of PAGE_CACHE_SIZE readahead pages, return a
* sensible upper limit.
*/

--