Re: [PATCH 36/42] VFS: export drop_pagecache_sb

[Nick Piggin <nickpiggin@yahoo.com.au>]

On Monday 10 December 2007 13:42, Erez Zadok wrote:
> Needed to maintain cache coherency after branch management.
>

Hmm, I'd much prefer to be able to sleep in invalidate_mapping_pages
before this function gets exported.

As it is, it can cause massive latencies on preemption and the inode_lock
so it is pretty much debug-only IMO. I'd rather it didn't escape into the
wild as is.

Either that or rework your cache coherency somehow.


> Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
> ---
>  fs/drop_caches.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/fs/drop_caches.c b/fs/drop_caches.c
> index 59375ef..90410ac 100644
> --- a/fs/drop_caches.c
> +++ b/fs/drop_caches.c
> @@ -3,6 +3,7 @@
>   */
>
>  #include <linux/kernel.h>
> +#include <linux/module.h>
>  #include <linux/mm.h>
>  #include <linux/fs.h>
>  #include <linux/writeback.h>
> @@ -12,7 +13,7 @@
>  /* A global variable is a bit ugly, but it keeps the code simple */
>  int sysctl_drop_caches;
>
> -static void drop_pagecache_sb(struct super_block *sb)
> +void drop_pagecache_sb(struct super_block *sb)
>  {
>  	struct inode *inode;
>
> @@ -24,6 +25,7 @@ static void drop_pagecache_sb(struct super_block *sb)
>  	}
>  	spin_unlock(&inode_lock);
>  }
> +EXPORT_SYMBOL(drop_pagecache_sb);
>
>  void drop_pagecache(void)
>  {