[PATCH 4/8] readahead: state based method: move readahead_ratio out of compute_thrashing_threshold()

[Fengguang Wu <wfg@mail.ustc.edu.cn>]

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Make compute_thrashing_threshold() a pure computing routine,
by moving the readahead_ratio policy out of it.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
---
 mm/readahead.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- linux-2.6.20-rc4-mm1.orig/mm/readahead.c
+++ linux-2.6.20-rc4-mm1/mm/readahead.c
@@ -1025,7 +1025,7 @@ static unsigned long compute_thrashing_t
 	stream_shift = ra_invoke_interval(ra);
 
 	/* future safe space */
-	ll = (uint64_t) stream_shift * (global_size >> 9) * readahead_ratio * 5;
+	ll = (uint64_t) stream_shift * global_size;
 	do_div(ll, global_shift);
 	ra_size = ll;
 
@@ -1063,6 +1063,7 @@ state_based_readahead(struct address_spa
 	la_old = la_size = ra->readahead_index - offset;
 	ra_old = ra_readahead_size(ra);
 	ra_size = compute_thrashing_threshold(ra, &remain_space);
+	ra_size = ra_size * readahead_ratio / 100;
 
 	if (page && remain_space <= la_size) {
 		rescue_pages(page, la_size);

--