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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2008-04-30 09:54:32 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-30 17:29:49 +0200 |
| commit | cf0ca9fe5dd9e3693d935757a7b2fc50fc576554 (patch) | |
| tree | c795c5271eda9fc67579fa3176c646b892dfdb41 /Documentation/ABI | |
| parent | pidns: make pid->level and pid_ns->level unsigned (diff) | |
| download | linux-cf0ca9fe5dd9e3693d935757a7b2fc50fc576554.tar.xz linux-cf0ca9fe5dd9e3693d935757a7b2fc50fc576554.zip | |
mm: bdi: export BDI attributes in sysfs
Provide a place in sysfs (/sys/class/bdi) for the backing_dev_info object.
This allows us to see and set the various BDI specific variables.
In particular this properly exposes the read-ahead window for all relevant
users and /sys/block/<block>/queue/read_ahead_kb should be deprecated.
With patient help from Kay Sievers and Greg KH
[mszeredi@suse.cz]
- split off NFS and FUSE changes into separate patches
- document new sysfs attributes under Documentation/ABI
- do bdi_class_init as a core_initcall, otherwise the "default" BDI
won't be initialized
- remove bdi_init_fmt macro, it's not used very much
[akpm@linux-foundation.org: fix ia64 warning]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Greg KH <greg@kroah.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-bdi | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi new file mode 100644 index 000000000000..b800cdda40bb --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -0,0 +1,46 @@ +What: /sys/class/bdi/<bdi>/ +Date: January 2008 +Contact: Peter Zijlstra <a.p.zijlstra@chello.nl> +Description: + +Provide a place in sysfs for the backing_dev_info object. +This allows us to see and set the various BDI specific variables. + +The <bdi> identifier can be either of the following: + +MAJOR:MINOR + + Device number for block devices, or value of st_dev on + non-block filesystems which provide their own BDI, such as NFS + and FUSE. + +default + + The default backing dev, used for non-block device backed + filesystems which do not provide their own BDI. + +Files under /sys/class/bdi/<bdi>/ +--------------------------------- + +read_ahead_kb (read-write) + + Size of the read-ahead window in kilobytes + +reclaimable_kb (read-only) + + Reclaimable (dirty or unstable) memory destined for writeback + to this device + +writeback_kb (read-only) + + Memory currently under writeback to this device + +dirty_kb (read-only) + + Global threshold for reclaimable + writeback memory + +bdi_dirty_kb (read-only) + + Current threshold on this BDI for reclaimable + writeback + memory + |