[PATCH 09/12] inode: remove iprune_sem

Dave Chinner
2011-06-02T07:02:55Z

From: Dave Chinner <dchinner@redhat.com>

Now that we have per-sb shrinkers and they are unregistered before
evict_inode() is called, there is not longer any race condition for
the iprune_sem to protect against. Hence we can remove it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/inode.c | 21 ---------------------
1 files changed, 0 insertions(+), 21 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 890d95e..167adfd 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -68,17 +68,6 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock);
__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_wb_list_lock);

/*
- * iprune_sem provides exclusion between the icache shrinking and the
- * umount path.
- *
- * We don't actually need it to protect anything in the umount path,
- * but only need to cycle through it to make sure any inode that
- * prune_icache_sb took off the LRU list has been fully torn down by the
- * time we are past evict_inodes.
- */
-static DECLARE_RWSEM(iprune_sem);
-
-/*
* Empty aops. Can be used for the cases where the user does not
* define any of the address_space operations.
*/
@@ -535,14 +524,6 @@ void evict_inodes(struct super_block *sb)
spin_unlock(&inode_sb_list_lock);

dispose_list(&dispose);
-
- /*
- * Cycle through iprune_sem to make sure any inode that prune_icache_sb
- * moved off the list before we took the lock has been fully torn
- * down.
- */
- down_write(&iprune_sem);
- up_write(&iprune_sem);
}

/**
@@ -628,7 +609,6 @@ void prune_icache_sb(struct super_block *sb, int nr_to_scan)
int nr_scanned;
unsigned long reap = 0;

- down_read(&iprune_sem);
spin_lock(&sb->s_inode_lru_lock);
for (nr_scanned = nr_to_scan; nr_scanned >= 0; nr_scanned--) {
struct inode *inode;
@@ -704,7 +684,6 @@ void prune_icache_sb(struct super_block *sb, int nr_to_scan)
spin_unlock(&sb->s_inode_lru_lock);

dispose_list(&freeable);
- up_read(&iprune_sem);
}

static void __wait_on_freeing_inode(struct inode *inode);
--
1.7.5.1