linux-stable.git/init/Kconfig, branch linux-2.6.20.y

[PATCH] handle SLOB with sparsemen

2006-12-22T16:55:49+00:00

This is to disallow to make SLOB with SMP or SPARSEMEM.  This avoids latent
troubles of SLOB with SLAB_DESTROY_BY_RCU.  And fix compile error.

Signed-off-by: Yasunori Goto 
Acked-by: Randy Dunlap 
Acked-by: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] CONFIG_VM_EVENT_COUNTER comment decrustify

2006-12-22T16:55:46+00:00

The VM event counters, enabled by CONFIG_VM_EVENT_COUNTERS, which provides
VM event counters in /proc/vmstat, has become more essential to
non-EMBEDDED kernel configurations than they were in the past.  Comments in
the code and the Kconfig configuration explanation were stale, downplaying
their role excessively.

Refresh those comments to correctly reflect the current role of VM event
counters.

Signed-off-by: Paul Jackson 
Acked-by: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Kconfig: fix spelling error in config KALLSYMS help text

2006-12-12T18:25:11+00:00

Signed-off-by: Jesper Juhl 
Acked-By: Randy Dunlap 
Signed-off-by: Adrian Bunk

[PATCH] io-accounting: core statistics

2006-12-10T17:55:41+00:00

The present per-task IO accounting isn't very useful.  It simply counts the
number of bytes passed into read() and write().  So if a process reads 1MB
from an already-cached file, it is accused of having performed 1MB of I/O,
which is wrong.

(David Wright had some comments on the applicability of the present logical IO accounting:

  For billing purposes it is useless but for workload analysis it is very
  useful

  read_bytes/read_calls  average read request size
  write_bytes/write_calls average write request size

  read_bytes/read_blocks ie logical/physical can indicate hit rate or thrashing
  write_bytes/write_blocks  ie logical/physical  guess since pdflush writes can
                                                be missed

  I often look for logical larger than physical to see filesystem cache
  problems.  And the bytes/cpusec can help find applications that are
  dominating the cache and causing slow interactive response from page cache
  contention.

  I want to find the IO intensive applications and make sure they are doing
  efficient IO.  Thus the acctcms(sysV) or csacms command would give the high
  IO commands).

This patchset adds new accounting which tries to be more accurate.  We account
for three things:

reads:

  attempt to count the number of bytes which this process really did cause
  to be fetched from the storage layer.  Done at the submit_bio() level, so it
  is accurate for block-backed filesystems.  I also attempt to wire up NFS and
  CIFS.

writes:

  attempt to count the number of bytes which this process caused to be sent
  to the storage layer.  This is done at page-dirtying time.

  The big inaccuracy here is truncate.  If a process writes 1MB to a file
  and then deletes the file, it will in fact perform no writeout.  But it will
  have been accounted as having caused 1MB of write.

  So...

cancelled_writes:

  account the number of bytes which this process caused to not happen, by
  truncating pagecache.

  We _could_ just subtract this from the process's `write' accounting.  But
  that means that some processes would be reported to have done negative
  amounts of write IO, which is silly.

  So we just report the raw number and punt this decision up to userspace.

Now, we _could_ account for writes at the physical I/O level.  But

- This would require that we track memory-dirtying tasks at the per-page
  level (would require a new pointer in struct page).

- It would mean that IO statistics for a process are usually only available
  long after that process has exitted.  Which means that we probably cannot
  communicate this info via taskstats.

This patch:

Wire up the kernel-private data structures and the accessor functions to
manipulate them.

Cc: Jay Lan 
Cc: Shailabh Nagar 
Cc: Balbir Singh 
Cc: Chris Sturtivant 
Cc: Tony Ernst 
Cc: Guillaume Thouvenin 
Cc: David Wright 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

CONFIG_SYSFS_DEPRECATED

2006-12-01T22:51:58+00:00

Provide a way to support older versions of udev that are shipped in
older distros.  If this option is disabled, it will also turn off the
compatible symlinks in sysfs that older programs might rely on.

When in doubt, or if running a distro older than 2006, say Yes here.

Signed-off-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman

[PATCH] sysctl: Undeprecate sys_sysctl

2006-11-09T02:29:24+00:00

The basic issue is that despite have been deprecated and warned about as a
very bad thing in the man pages since its inception there are a few real
users of sys_sysctl.  It was my assumption that because sysctl had been
deprecated for all of 2.6 there would be no user space users by this point,
so I initially gave sys_sysctl a very short deprecation period.

Now that I know there are a few real users the only sane way to proceed
with deprecation is to push the time limit out to a year or two work and
work with distributions that have big testing pools like fedora core to
find these last remaining users.

Which means that the sys_sysctl interface needs to be maintained in the
meantime.

Since I have provided a technical measure that allows us to add new sysctl
entries without reserving more binary numbers I believe that is enough to
fix the sys_sysctl binary interface maintenance problems, because there is
no longer a need to change the binary interface at all.

Since the sys_sysctl implementation needs to stay around for a while and
the worst of the maintenance issues that caused us to occasionally break
the ABI have been addressed I don't see any advantage in continuing with
the removal of sys_sysctl.

So instead of merely increasing the deprecation period this patch removes
the deprecation of sys_sysctl and modifies the kernel to compile the code
in by default.

With committing to maintain sys_sysctl we get all of the advantages of a
fast interface for anything that needs it.  Currently sys_sysctl is about
5x faster than /proc/sys, for the same string data.

Signed-off-by: Eric W. Biederman 
Acked-by: Alan Cox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] uml: use DEFCONFIG_LIST to avoid reading host's config

2006-10-20T17:26:36+00:00

This should make sure that, for UML, host's configuration files are not
considered, which avoids various pains to the user.  Our dependency are such
that the obtained Kconfig will be valid and will lead to successful
compilation - however they cannot prevent an user from disabling any boot
device, and if an option is not set in the read .config (say
/boot/config-XXX), with make menuconfig ARCH=um, it is not set.  This always
disables UBD and all console I/O channels, which leads to non-working UML
kernels, so this bothers users - especially now, since it will happen on
almost every machine (/boot/config-`uname -r` exists almost on every machine).
 It can be workarounded with make defconfig ARCH=um, but it is non-obvious and
can be avoided, so please _do_ merge this patch.

Given the existence of options, it could be interesting to implement
(additionally) "option required" - with it, Kconfig will refuse reading a
.config file (from wherever it comes) if the given option is not set.  With
this, one could mark with it the option characteristic of the given
architecture (it was an old proposal of Roman Zippel, when I pointed out our
problem):

config UML
	option required
	default y

However this should be further discussed:
*) for x86, it must support constructs like:

==arch/i386/Kconfig==
config 64BIT
	option required
	default n
where Kconfig must require that CONFIG_64BIT is disabled or not present in the
read .config.

*) do we want to do such checks only for the starting defconfig or also for
   .config? Which leads to:
*) I may want to port a x86_64 .config to x86 and viceversa, or even among more
   different archs. Should that be allowed, and in which measure (the user may
   force skipping the check for a .config or it is only given a warning by
   default)?

Cc: Roman Zippel 
Cc: 
Signed-off-by: Paolo 'Blaisorblade' Giarrusso 
Cc: Jeff Dike 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] IPC namespace core

2006-10-02T14:57:22+00:00

This patch set allows to unshare IPCs and have a private set of IPC objects
(sem, shm, msg) inside namespace.  Basically, it is another building block of
containers functionality.

This patch implements core IPC namespace changes:
- ipc_namespace structure
- new config option CONFIG_IPC_NS
- adds CLONE_NEWIPC flag
- unshare support

[clg@fr.ibm.com: small fix for unshare of ipc namespace]
[akpm@osdl.org: build fix]
Signed-off-by: Pavel Emelianov 
Signed-off-by: Kirill Korotaev 
Signed-off-by: Cedric Le Goater 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespaces: utsname: implement utsname namespaces

2006-10-02T14:57:21+00:00

This patch defines the uts namespace and some manipulators.
Adds the uts namespace to task_struct, and initializes a
system-wide init namespace.

It leaves a #define for system_utsname so sysctl will compile.
This define will be removed in a separate patch.

[akpm@osdl.org: build fix, cleanup]
Signed-off-by: Serge Hallyn 
Cc: Kirill Korotaev 
Cc: "Eric W. Biederman" 
Cc: Herbert Poetzl 
Cc: Andrey Savochkin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] csa: Extended system accounting over taskstats

2006-10-01T07:39:29+00:00

Add extended system accounting handling over taskstats interface.  A
CONFIG_TASK_XACCT flag is created to enable the extended accounting code.

Signed-off-by: Jay Lan 
Cc: Shailabh Nagar 
Cc: Balbir Singh 
Cc: Jes Sorensen 
Cc: Chris Sturtivant 
Cc: Tony Ernst 
Cc: Guillaume Thouvenin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds