FS-Cache: Add use of /proc and presentation of statistics

Make FS-Cache create its /proc interface and present various statistical
information through it.  Also provide the functions for updating this
information.

These features are enabled by:

	CONFIG_FSCACHE_PROC
	CONFIG_FSCACHE_STATS
	CONFIG_FSCACHE_HISTOGRAM

The /proc directory for FS-Cache is also exported so that caching modules can
add their own statistics there too.

The FS-Cache module is loadable at this point, and the statistics files can be
examined by userspace:

	cat /proc/fs/fscache/stats
	cat /proc/fs/fscache/histogram

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>

1 files changed, 0 insertions, 6 deletions

diff --git a/Documentation/filesystems/caching/backend-api.txt b/Documentation/filesystems/caching/backend-api.txt
index 17723053aa91..382d52cdaf2d 100644
--- a/Documentation/filesystems/caching/backend-api.txt
+++ b/Documentation/filesystems/caching/backend-api.txt
@@ -100,12 +100,6 @@ A sysfs directory called /sys/fs/fscache/<cachetag>/ is created if CONFIG_SYSFS
 is enabled.  This is accessible through the kobject struct fscache_cache::kobj
 and is for use by the cache as it sees fit.
 
-The cache driver may create itself a directory named for the cache type in the
-/proc/fs/fscache/ directory.  This is available if CONFIG_FSCACHE_PROC is
-enabled and is accessible through:
-
-        struct proc_dir_entry *proc_fscache;
-
 
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 RELEVANT DATA STRUCTURES