This patch removes prototypes for the generic_file_open and
generic_file_llseek functions.
Besides being superfluous because they are already present in fs.h, they
were also wrong because the actual functions aren't weak functions.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch contains the following updates to the help texts:
- QUOTA: most people will get the quota utilities from their
distribution, and if not the mini-HOWTO will tell them
- QFMT_V2: quota utilities 3.01 are no longer recent, they are now
ancient
and 3.01 is lower than the minimal version documented in
Documentation/Changes
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This interface is said to be commonly used in germany: "The patch has been
proven to work fine in a beige G3 Mac."
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=262324
Signed-off-by: maximilian attems <janitor@sternwelten.at>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
cleanup of deadline_dispatch_requests():
- replace drq selection with hopefully clearer while semantically the
same construct: take write request, if there is any, otherwise take read
one, or NULL if none exist.
- kill unused other_dir.
Signed-off-by: Nikita Danilov <nikita@clusterfs.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since early userspace was added, there's no way to override which init to
run from it. Some people tack on an extra cpio archive with a link from
/init depending on what they want to run, but that's sometimes impractical.
Changing the "init=" to also override the early userspace isn't feasible,
since it is still used to indicate what init to run from disk when early
userspace has completed doing whatever it's doing (i.e. load filesystem
modules and drivers).
Instead, introduce "rdinit=" and make it override the default "/init" if
specified.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes bug titled "sunrpc as module and bad proc/sys link count"
reported by Jiri Slaby.
The problem was, that only proc_dir_entry->nlink was updated and the
corresponding inode->i_nlink was not. The fix is to implement the
inode->getattr() method, and update i_nlink (if necessary).
A quick audit of proc code shows that no other attribute changes after
creation.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With "-W -Wno-unused -Wno-sign-compare" I get the following compile warning:
CC kernel/workqueue.o
kernel/workqueue.c: In function `workqueue_cpu_callback':
kernel/workqueue.c:504: warning: ordered comparison of pointer with integer zero
On error create_workqueue_thread() returns NULL, not negative pointer, so
following trivial patch suggests itself.
Signed-off-by: Mika Kukkonen <mikukkon@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add fsnotify_xattr() hook to removexattr().
Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: John McCtuchan <ttb@tentacle.dhs.org>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the Dell Systems Management Base Driver with sysfs support.
This driver has been tested with Dell OpenManage.
Signed-off-by: Doug Warzecha <Douglas_Warzecha@dell.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Upgrade the request_firmware_nowait function to not start the hotplug
action on a firmware update.
This patch is tested along with dell_rbu driver on i386 and x86-64 systems.
Signed-off-by: Abhay Salunke <Abhay_Salunke@dell.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
This speeds up directory reads for large FAT partitions, if the buffercache
has to be filled from the drive. Following values were taken from:
$ time find path_to_freshly_mounted_fat > /dev/null
on an otherwise idle system.
FAT with 16KB Clusters on IDE attached drive: Factor 2
FAT with 32KB Clusters on USB2 attached drive: Factor 10 (!)
Its less than 1/10 slower, if the buffercache is uptodate.
The patch introduces the new function fat_dir_readahead().
fat_dir_readahead() calls sb_breadahead() to readahead a whole cluster,
if the requested sector is the first one in a cluster.
It is usefull to do this, because on FAT directories occupy whole
clusters, with the exception of FAT12/FAT16 root dirs.
Readahead is only done, if the cluster's first sector is not uptodate
to avoid overhead, when the buffer cache is already uptodate.
Note that under memory pressure, the maximal byte count wasted
(read: has to be red from disk twice) is 1 cluster's size. Thats 64KB.
fat_dir_readahead() is called from fat__get_entry().
There is also an unrelated cleanup at one spot:
if (bh)
brelse(bh);
is replaced with:
brelse(bh);
brelse() can handle NULL pointer arguments by itself.
Signed-off-by: Karsten Wiese <annabellesgarden@yahoo.de>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change the sequence of operations performed during module loading to flush
the instruction cache before module parameters are processed. If a module
has parameters of an unusual type that cannot be handled using the standard
accessor functions param_set_xxx and param_get_xxx, it has to to provide a
set of accessor functions for this type. This requires module code to be
executed during parameter processing, which is of course only possible
after the icache has been flushed.
Signed-off-by: Thomas Koeller <thomas@koeller.dyndns.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change the /proc/sysvipc/shm|sem|msg files to use the generic seq_file
implementation for struct ipc_ids.
Signed-off-by: Mike Waychison <mikew@google.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following two patches convert /proc/sysvipc/* to use seq_file.
This gives us the following:
- Self-consistent IPC records in proc.
- O(n) reading of the files themselves.
This patch:
Add a generic method for ipc types to be displayed using seq_file. This
patch abstracts out seq_file iterating over struct ipc_ids into ipc/util.c
Signed-off-by: Mike Waychison <mikew@google.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When registering an RPC cache, cache_register() always sets the owner as the
sunrpc module. However, there are RPC caches owned by other modules. With
the incorrect owner setting, the real owning module can be removed potentially
with an open reference to the cache from userspace.
For example, if one were to stop the nfs server and unmount the nfsd
filesystem, the nfsd module could be removed eventhough rpc.idmapd had
references to the idtoname and nametoid caches (i.e.
/proc/net/rpc/nfs4.<cachename>/channel is still open). This resulted in a
system panic on one of our machines when attempting to restart the nfs
services after reloading the nfsd module.
The following patch adds a 'struct module *owner' field in struct
cache_detail. The owner is further assigned to the struct proc_dir_entry
in cache_register() so that the module cannot be unloaded while user-space
daemons have an open reference on the associated file under /proc.
Signed-off-by: Bruce Allan <bwa@us.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the DMA_32BIT_MASK constant from dma-mapping.h when calling
pci_set_dma_mask() or pci_set_consistent_dma_mask() This patch includes
dma-mapping.h explicitly because it caused errors on some architectures
otherwise. See http://marc.theaimsgroup.com/?t=108001993000001&r=1&w=2 for
details
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Stelian Pop <stelian@popies.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We don't reset the cache hit count until after readahead does a successful
readahead. This seems to leave a corner case open where we miss in cache,
but don't restart the readhead right away.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Seems pointless to require .c files to test CONFIG_PNP_DEBUG and
conditionally define DEBUG before including <linux/pnp.h>. Just test
CONFIG_PNP_DEBUG directly in pnp.h.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Christoph Lameter <clameter@engr.sgi.com>
When using a time interpolator that is susceptible to jitter there's
potentially contention over a cmpxchg used to prevent time from going
backwards. This is unnecessary when the caller holds the xtime write
seqlock as all readers will be blocked from returning until the write is
complete. We can therefore allow writers to insert a new value and exit
rather than fight with CPUs who only hold a reader lock.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Newer Sony VAIO models (VGN-S480, VGN-S460, VGN-S3XP etc) use a new method to
initialize the SPIC device. The new way to initialize (and disable) the
device comes directly from the AML code in the _CRS, _SRS and _DIS methods
from the DSDT table. This patch adds support for the new models.
Signed-off-by: Erik Waling <erikw@acc.umu.se>
Signed-off-by: Stelian Pop <stelian@popies.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
this is the last serial driver not using initcalls.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: <jeff@uclinux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
this gets rid of the last two explicit initializations in misc.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I passed init=/mylinuxrc to the kernel on the command line. The kernel
silently dropped down to exec /sbin/init. It turned out that /mylinuxrc
had improper permissions. Without any warning message from the kernel that
something was wrong it took awhile to find the issue. The patch below adds
a warning.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If /etc/mtab is a regular file all of the mount options (of a file system)
are written to /etc/mtab by the mount command. The quota tools look there
for the quota strings for their operation. If, however, /etc/mtab is a
symlink to /proc/mounts (a "good thing" in some environments) the tools
don't write anything - they assume the kernel will take care of things.
While the quota options are sent down to the kernel via the mount system
call and the file system codes handle them properly unfortunately there is
no code to echo the quota strings into /proc/mounts and the quota tools
fail in the symlink case.
The attached patchs modify the EXT[2|3] and JFS codes to add the necessary
hooks. The show_options function of each file system in these patches
currently deal with only those things that seemed related to quotas;
especially in the EXT3 case more can be done (later?).
Jan Kara also noted the difficulty in moving these changes above the FS
codes responding similarly to myself to Andrew's comment about possible
VFS migration. Issue summary:
- FS codes have to process the entire string of options anyway.
- Only FS codes that use quotas must have a show_options function (for
quotas to work properly) however quotas are only used in a small number
of FS.
- Since most of the quota using FS support other options these FS codes
should have the a show_options function to show those options - and the
quota echoing becomes virtually negligible.
Based on feedback I have modified my patches from the original:
JFS a missing patch has been restored to the posting
EXT[2|3] and JFS always use the show_options function
- Each FS has at least one FS specific option displayed
- QUOTA output is under a CONFIG_QUOTA ifdef
- a follow-on patch will add a multitude of options for each FS
EXT[2|3] and JFS "quota" is treated as "usrquota"
EXT3 journalled data check for journalled quota removed
EXT[2|3] mount when quota specified but not compiled in
- no changes from my original patch. I tested the patch and the codes
warn but
- still mount. With all due respection I believe the comments
otherwise were a
- misread of the patch. Please reread/test and comment. XFS patch
removed - the XFS team already made the necessary changes EXT3 mixing
old and new quotas are handled differently (not purely exclusive)
- if old and new quotas for the same type are used together the old
type is silently depricated for compatability (e.g. usrquota and
usrjquota)
- mixing of old and new quotas is an error (e.g. usrjquota and
grpquota)
Signed-off-by: Mark Bellon <mbellon@mvista.com>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ensure that sound/arm/Makefile is sanely organised so that additions to it
don't break all other patches out there. This means I only have to adjust
the line numbers in my patch queue rather than having to re-generate by
hand those which touch this file.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ISAPNP, PNPBIOS, and PNPACPI all had their own kmalloc wrappers that
reimplemented kcalloc(). Remove the wrappers and just use kcalloc()
directly.
Note that this also removes the PNPBIOS error message when the kmalloc
fails.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ToPIC95 brides (and maybe some other too) require to use the ExCA registers
to power up the socket if a 16bit card is pluged. allow socket drivers to
set a flag so that yenta does just that. also clean up yenta_get_status()
a bit to use the new yenta_get_power() function.
Side note: ToPIC97 bridges (at least in Rev.5 i have) don't require this.
Ryan Underwood <nemesis-lists@icequake.net> said:
According to the mail that David Hinds received from a Toshiba engineer,
ToPIC95 and 97 do require this, and ToPIC100 does not. Maybe you have a
later revision.
For all chips, 16-bit cards can be enabled through ExCA. So doesn't it
make sense just to make this the default behavior for all Toshiba chips,
to avoid corner cases showing up later?
Daniel responded:
I disagree with ryan to change anything for topic97 bridges. they work.
and I couldn't find (read google) any report of a topic97 breaking on
applying power with the CB registers.
I'm having several toshba notebooks at work (and home) with topic95,97,100
bridges. Only the ones with a topic95 didn't work.
Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The size of auxiliary vector is fixed at 42 in linux/sched.h. But it isn't
very obvious when looking at linux/elf.h. This patch adds AT_VECTOR_SIZE
so that we can change it if necessary when a new vector is added.
Because of include file ordering problems, doing this necessitated the
extraction of the AT_* symbols into a standalone header file.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Simple patch to radix_tree_tag_get() to return different values for non
present node and tag unset.
The function is not used by any in-kernel callers (yet), but this
information is definitely useful.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- There is frequent use of indirections in the radix code. This patch
removes those indirections, makes the code more readable and allows
the compilers to generate better code.
- Removing indirections allows the removal of several casts.
- Removing indirections allows the reduction of the radix_tree_path
size from 3 to 2 words.
- Use pathp-> consistently.
- Remove unnecessary tmp variable in radix_tree_insert
- Separate the upper layer processing from the lowest layer in __lookup()
in order to make it easier to understand what is going on and allow
compilers to generate better code for the loop.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds support for powering Zaurus's video up and down. PDA without
screen is kind of useless, so it is quite important... I'll have to figure
out how to really control the frontlight, because LCD without that is quite
hard to read.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
All users have been converted.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jens:
->bi_set is totally unnecessary bloat of struct bio. Just define a proper
destructor for the bio and it already knows what bio_set it belongs too.
Peter:
Fixed the bugs.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Local symbols generated by gcc start with a `$'; no point in including them
in the kernel.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch contains the following cleanups:
- make needlessly global functions static
- journal.c: remove the unused global function __journal_internal_check
and move the check to journal_init
- remove the following write-only global variable:
- journal.c: current_journal
- remove the following unneeded EXPORT_SYMBOL:
- journal.c: journal_recover
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When I first wrote the compat layer patches, I was somewhat cavalier about
the definition of compat_uid_t and compat_gid_t (or maybe I just
misunderstood :-)). This patch makes the compat types much more consistent
with the types we are being compatible with and hopefully will fix a few
bugs along the way.
compat type type in compat arch
__compat_[ug]id_t __kernel_[ug]id_t
__compat_[ug]id32_t __kernel_[ug]id32_t
compat_[ug]id_t [ug]id_t
The difference is that compat_uid_t is always 32 bits (for the archs we
care about) but __compat_uid_t may be 16 bits on some.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In sound/isa/Kconfig, select ISAPNP and depend on ISAPNP are intermixed,
resulting in funny behaviour. (Soundcarts get selectable if other
soundcards are selected).
This patch changes the "depend on ISAPNP"s to select.
Signed-Off-By: Bodo Eggert <7eggert@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Bypass an inotify-related fastpath spinlock and several function calls on
systems which have no inotify watches registered.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Uses of RCU for dynamically changeable NMI handlers need to use the new
rcu_dereference() and rcu_assign_pointer() facilities. This change makes
it clear that these uses are safe from a memory-barrier viewpoint, but the
main purpose is to document exactly what operations are being protected by
RCU. This has been tested on x86 and x86-64, which are the only
architectures affected by this change.
Signed-off-by: <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The attached patch prevents oopses interleaving with characters from
other printks on other CPUs by only breaking the lock if the oops is
happening on the machine holding the lock.
It might be better if the oops generator got the lock and then called an
inner vprintk routine that assumed the caller holds the lock, thus
making oops reports "atomic".
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move some more frequently read variables that showed up during some of our
performance tests as sometimes ending up in hot cachelines to the
read_mostly section.
Fix: Move the __read_mostly from before hpet_usec_quotient to follow the
variable like the other uses of __read_mostly.
Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Christoph Lameter <christoph@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch changes the way the compression algorithm works. The base
algorithm is similiar to the previous but we force the compressed token
size to 2.
Having a fixed size compressed token allows for a lot of optimizations, and
that in turn allows this code to run over *all* the symbols faster than it
did before over just a subset.
Having it work over all the symbols will make it behave better when symbols
change positions between passes, and the "inconsistent kallsyms" messages
should become less frequent.
In my tests the compression ratio was degraded by about 0.5%, but the
results will depend greatly on the number of symbols to compress.
Signed-off-by: Paulo Marques <pmarques@grupopie.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
This patch adds a new kernel debug feature: CONFIG_DETECT_SOFTLOCKUP.
When enabled then per-CPU watchdog threads are started, which try to run
once per second. If they get delayed for more than 10 seconds then a
callback from the timer interrupt detects this condition and prints out a
warning message and a stack dump (once per lockup incident). The feature
is otherwise non-intrusive, it doesnt try to unlock the box in any way, it
only gets the debug info out, automatically, and on all CPUs affected by
the lockup.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-Off-By: Matthias Urlichs <smurf@smurf.noris.de>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adrian Bunk