Here's the latest version of relayfs, against linux-2.6.11-mm2. I'm hoping
you'll consider putting this version back into your tree - the previous
rounds of comment seem to have shaken out all the API issues and the number
of comments on the code itself have also steadily dwindled.
This patch is essentially the same as the relayfs redux part 5 patch, with
some minor changes based on reviewer comments. Thanks again to Pekka
Enberg for those. The patch size without documentation is now a little
smaller at just over 40k. Here's a detailed list of the changes:
- removed the attribute_flags in relay open and changed it to a
boolean specifying either overwrite or no-overwrite mode, and removed
everything referencing the attribute flags.
- added a check for NULL names in relayfs_create_entry()
- got rid of the unnecessary multiple labels in relay_create_buf()
- some minor simplification of relay_alloc_buf() which got rid of a
couple params
- updated the Documentation
In addition, this version (through code contained in the relay-apps tarball
linked to below, not as part of the relayfs patch) tries to make it as easy
as possible to create the cooperating kernel/user pieces of a typical and
common type of logging application, one where kernel logging is kicked off
when a user space data collection app starts and stops when the collection
app exits, with the data being automatically logged to disk in between. To
create this type of application, you basically just include a header file
(relay-app.h, included in the relay-apps tarball) in your kernel module,
define a couple of callbacks and call an initialization function, and on
the user side call a single function that sets up and continuously monitors
the buffers, and writes data to files as it becomes available. Channels
are created when the collection app is started and destroyed when it exits,
not when the kernel module is inserted, so different channel buffer sizes
can be specified for each separate run via command-line options. See the
README in the relay-apps tarball for details.
Also included in the relay-apps tarball are a couple examples
demonstrating how you can use this to create quick and dirty kernel
logging/debugging applications. They are:
- tprintk, short for 'tee printk', which temporarily puts a kprobe on
printk() and writes a duplicate stream of printk output to a relayfs
channel. This could be used anywhere there's printk() debugging code
in the kernel which you'd like to exercise, but would rather not have
your system logs cluttered with debugging junk. You'd probably want
to kill klogd while you do this, otherwise there wouldn't be much
point (since putting a kprobe on printk() doesn't change the output
of printk()). I've used this method to temporarily divert the packet
logging output of the iptables LOG target from the system logs to
relayfs files instead, for instance.
- klog, which just provides a printk-like formatted logging function
on top of relayfs. Again, you can use this to keep stuff out of your
system logs if used in place of printk.
The example applications can be found here:
http://prdownloads.sourceforge.net/dprobes/relay-apps.tar.gz?download
From: Christoph Hellwig <hch@lst.de>
avoid lookup_hash usage in relayfs
Signed-off-by: Tom Zanussi <zanussi@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:
* dnotify requires the opening of one fd per each directory
that you intend to watch. This quickly results in too many
open files and pins removable media, preventing unmount.
* dnotify is directory-based. You only learn about changes to
directories. Sure, a change to a file in a directory affects
the directory, but you are then forced to keep a cache of
stat structures.
* dnotify's interface to user-space is awful. Signals?
inotify provides a more usable, simple, powerful solution to file change
notification:
* inotify's interface is a system call that returns a fd, not SIGIO.
You get a single fd, which is select()-able.
* inotify has an event that says "the filesystem that the item
you were watching is on was unmounted."
* inotify can watch directories or files.
Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.
See Documentation/filesystems/inotify.txt.
Signed-off-by: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This updates the CFQ io scheduler to the new time sliced design (cfq
v3). It provides full process fairness, while giving excellent
aggregate system throughput even for many competing processes. It
supports io priorities, either inherited from the cpu nice value or set
directly with the ioprio_get/set syscalls. The latter closely mimic
set/getpriority.
This import is based on my latest from -mm.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds functions for encoding and decoding POSIX ACLs for the NFSACL
protocol extension, and the GETACL and SETACL RPCs. The implementation is
compatible with NFSACL in Solaris.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Tom Zanussi