Hello,

This optimizes bh_lru_install(). It's a hot spot I think.  The bh_lru is well
manipulated now so we can use put_bh() as a substitute for the first __brelse()
here, and a bogus BUG_ON() can be removed safely.  We evict at the right place
too.  Boot tested.

        Coywolf


Signed-off-by: Coywolf Qi Hunt <[EMAIL PROTECTED]>
---

 buffer.c |   17 ++++++-----------
 1 files changed, 6 insertions(+), 11 deletions(-)

--- 2.6.13-rc6-mm2/fs/buffer.c~orig     2005-08-23 13:42:04.000000000 +0800
+++ 2.6.13-rc6-mm2/fs/buffer.c  2005-08-25 16:04:21.000000000 +0800
@@ -1356,7 +1356,6 @@ static inline void check_irqs_on(void)
  */
 static void bh_lru_install(struct buffer_head *bh)
 {
-       struct buffer_head *evictee = NULL;
        struct bh_lru *lru;
 
        check_irqs_on();
@@ -1372,15 +1371,14 @@ static void bh_lru_install(struct buffer
                for (in = 0; in < BH_LRU_SIZE; in++) {
                        struct buffer_head *bh2 = lru->bhs[in];
 
-                       if (bh2 == bh) {
-                               __brelse(bh2);
-                       } else {
+                       if (bh2 == bh)
+                               put_bh(bh2);
+                       else {
                                if (out >= BH_LRU_SIZE) {
-                                       BUG_ON(evictee != NULL);
-                                       evictee = bh2;
-                               } else {
+                                       if (bh2)
+                                               __brelse(bh2);  /* evict bh2 */
+                               } else
                                        bhs[out++] = bh2;
-                               }
                        }
                }
                while (out < BH_LRU_SIZE)
@@ -1388,9 +1386,6 @@ static void bh_lru_install(struct buffer
                memcpy(lru->bhs, bhs, sizeof(bhs));
        }
        bh_lru_unlock();
-
-       if (evictee)
-               __brelse(evictee);
 }
 
 /*
-
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