Commit Graph

568 Commits

Author SHA1 Message Date
Adrian Bunk 03502faa25 remove Documentation/smp.txt
After seeing the filename I'd have expected something about the
implementation of SMP in the Linux kernel - not some notes on kernel
configuration and building trivialities noone would search at this
place.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Alan Cox <alan@redhat.com>
2008-02-03 15:50:21 +02:00
Sam Ravnborg 01ba2bdc6b all archs: consolidate init and exit sections in vmlinux.lds.h
This patch consolidate all definitions of .init.text, .init.data
and .exit.text, .exit.data section definitions in
the generic vmlinux.lds.h.

This is a preparational patch - alone it does not buy
us much good.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:17 +01:00
Martin Schwidefsky 9d40d2e395 [S390] replace lock_cpu_hotplug with get_online_cpus
Git commit 86ef5c9a8e forgot a few
lock_cpu_hotplug/unlock_cpu_hotplug pairs in arch/s390/kernel/smp.c

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:33 +01:00
Jan Engelhardt 5c81cdbeff [S390] constify function pointer tables.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:32 +01:00
Hisashi Hifumi 894cdde26b [S390] do local_irq_restore while spinning in spin_lock_irqsave.
In s390's spin_lock_irqsave, interrupts remain disabled while
spinning. In other architectures like x86 and powerpc, interrupts are
re-enabled while spinning if IRQ is not masked before spin_lock_irqsave
is called.

The following patch re-enables interrupts through local_irq_restore
while spinning for a lock acquisition.
This can improve system response.

[heiko.carstens@de.ibm.com: removed saving of pc]

Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:31 +01:00
Carsten Otte dab5209cd8 [S390] add smp_call_function_mask
This patch adds the s390 variant for smp_call_function_mask(). The
implementation is pretty straight forward using the wrapper
__smp_call_function_map() which already takes a cpumask_t argument.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:31 +01:00
WANG Cong 53360fb196 [S390] Remove TOPDIR from Makefile
This patch removes TOPDIR from arch/s390/kernel/Makefile.

Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:29 +01:00
Roland McGrath 0ac30be461 [S390] single-step cleanup
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:27 +01:00
Martin Schwidefsky ea29ee16e6 [S390] Move NOTES and BUG_TABLE.
Move the NOTES and BUG_TABLE section in the linker script to the
read-only sections right after the text section.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:26 +01:00
Joe Perches c2e3bbac72 [S390] arch/s390/: Spelling fixes
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:24 +01:00
Michael Holzheu 48657d223d [S390] Use diag308 subcodes 3 and 6 for reboot and dump when possible.
This patch fixes a problem with the following scenario:
 1. Linux booted from DASD "A"
 2. Reboot from DASD "B" using "/sys/firmware/reipl/ccw/device"
 3. Reboot DASD "B"
Without this patch in step 3 on newer s390 systems under LPAR instead of
DASD "B", DASD "A" will be booted. The reason is that in step 2 we use CCW
reipl and in step 3 we use DIAG308 (subcode 3) reipl. DIAG308 does not
notice the CCW reipl and still thinks that it has to reboot DASD "A".
Before applying this fix, ensure to have MCF RJ9967101E or z9 GA3 base driver
installed.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:24 +01:00
Christian Borntraeger a2fd64d6aa [S390] vmemmap: allocate struct pages before 1:1 mapping
We have seen an oops in an OOM situation, where show_mem tried to
access the struct page of a dcss segment. The vmemmap code has
already created the 1:1 mapping but failed allocating the struct
pages. In the OOM case, show_mem now walks the memory. It uses
pfn_valid to detect if it may access the struct page. In the case
described above, the mapping was established and pfn_valid returned
true. As the struct pages were not allocated, the kernel oopsed.

We have to ensure that we have created the struct pages, before we
add a mapping pointing to the pages.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:23 +01:00
Michael Holzheu d09293aee9 [S390] Initialize sclp_ipl_info
The sclp ipl information has not been initialized. Therefore the ipl loadparm
and the "has_dump" flag have not been set correctly.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:22 +01:00
Heiko Carstens 1cb6bb4bbd [S390] Allocate and free cpu lowcores and stacks when needed/possible.
No need to preallocate the per cpu lowcores and stacks.
Savings are 28-32k per offline cpu.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:22 +01:00
Denis Cheng c11ca97ee9 [S390] use LIST_HEAD instead of LIST_HEAD_INIT
single list_head variable initialized with LIST_HEAD_INIT could almost
always can be replaced with LIST_HEAD declaration, this shrinks the code
and looks better.

Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:21 +01:00
Michael Holzheu c654749777 [S390] Load disabled wait psw instead of stopping cpu on halt.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:20 +01:00
Michael Holzheu 99ca4e582d [S390] kernel: Shutdown Actions Interface
In case of a kernel panic it is currently possible to specify that a dump
should be created, the system should be rebooted or stopped. Virtual sysfs
files under the directory /sys/firmware/ are used for that configuration.
In addition to that, there are kernel parameters 'vmhalt', 'vmpoff'
and 'vmpanic', which can be used to specify z/VM commands, which are
automatically executed in case of halt, power off or a kernel panic.
This patch combines both functionalities and allows to specify the z/VM CP
commands also via sysfs attributes. In addition to that, it enhances the
existing handling of shutdown triggers (e.g. halt or panic) and associated
shutdown actions (e.g. dump or reipl) and makes it more flexible.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:19 +01:00
Joe Perches cfe7381cea [S390] arch/s390: Add missing "space"
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:18 +01:00
Jan Glauber 3f5615e012 [S390] crypto: move s390 Kconfig options.
Move s390 crypto Kconfig options to drivers/crypto/Kconfig to have all
hardware crypto devices in one place.

This also makes messing up the kernel source tree easier for some people.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:17 +01:00
Heiko Carstens 48483b3290 [S390] Get rid of additional_cpus kernel parameter.
It caused only a lot of confusion. From now on cpu hotplug of up to
NR_CPUS will work by default. If somebody wants to limit that then
the possible_cpus parameter can be used.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:15 +01:00
Heiko Carstens 3b4beb3175 [S390] Remove owner_pc member from raw_spinlock_t.
Used to contain the address of the holder of the lock. But since the
spinlock code is not inlined anymore all locks contain the same address
anyway. And since in addtition nobody complained about that for ages
its obviously unused. So remove it.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:14 +01:00
Heiko Carstens 9f4b0ba81f [S390] Get rid of HOLES_IN_ZONE requirement.
Align everything to MAX_ORDER so we can get rid of the extra checks.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:13 +01:00
Heiko Carstens 5c699714d0 [S390] Print kernel version in dump_stack() and show_regs().
Also print PREEMPT and/or SMP if the kernel was configured that way.
Makes s390 look a bit more like other architectures.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:12 +01:00
Christian Borntraeger 5fd9c6e214 [S390] Change vmalloc defintions
Currently the vmalloc area starts at a dynamic address depending on
the memory size. There was also an 8MB security hole after the
physical memory to catch out-of-bounds accesses.
We can simplify the code by putting the vmalloc area explicitely at
the top of the kernel mapping and setting the vmalloc size to a fixed
value of 128MB/128GB for 31bit/64bit systems. Part of the vmalloc
area will be used for the vmem_map. This leaves an area of 96MB/1GB
for normal vmalloc allocations.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:12 +01:00
Martin Schwidefsky 6f457e1a14 [S390] Fix tlb flushing with idte.
The clear-by-asce operation of the idte instruction gets an asce
(address-space-control-element) as argument to specify which TLBs
need to get flushed. The current code passes a plain pointer to
the start of the pgd without the additional bits which would make
the pointer an asce. The current machines don't mind the difference
but a future model might want to use the designation type control
bits in the asce as a filter for the TLBs to flush.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:10 +01:00
Heiko Carstens 08d0796827 [S390] Standby cpu activation/deactivation.
Add a new interface so that cpus can be put into standby state and
configured state.
Only offline cpus can be put into standby state or configured state.
For that the new percpu sysfs attribute "configure" must be used.
To put a cpu in standby state a "0" must be written to the attribute.
In order to switch it into configured state a "1" must be written to
the attribute.
Only cpus in configured state can be brought online.
In addition this patch introduces a static mapping of physical to
logical cpus. As a result only the sysfs directories of present cpus
will be created. To scan for new cpus the new sysfs attribute "rescan"
must be used.
Writing to /sys/devices/system/cpu/rescan will trigger a rescan of
cpus and will create directories for new cpus.

On IPL only configured cpus will be used. And on reboot/shutdown all
cpus will remain in their current state (configured/standby).

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:09 +01:00
Linus Torvalds eba0e319c1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (125 commits)
  [CRYPTO] twofish: Merge common glue code
  [CRYPTO] hifn_795x: Fixup container_of() usage
  [CRYPTO] cast6: inline bloat--
  [CRYPTO] api: Set default CRYPTO_MINALIGN to unsigned long long
  [CRYPTO] tcrypt: Make xcbc available as a standalone test
  [CRYPTO] xcbc: Remove bogus hash/cipher test
  [CRYPTO] xcbc: Fix algorithm leak when block size check fails
  [CRYPTO] tcrypt: Zero axbuf in the right function
  [CRYPTO] padlock: Only reset the key once for each CBC and ECB operation
  [CRYPTO] api: Include sched.h for cond_resched in scatterwalk.h
  [CRYPTO] salsa20-asm: Remove unnecessary dependency on CRYPTO_SALSA20
  [CRYPTO] tcrypt: Add select of AEAD
  [CRYPTO] salsa20: Add x86-64 assembly version
  [CRYPTO] salsa20_i586: Salsa20 stream cipher algorithm (i586 version)
  [CRYPTO] gcm: Introduce rfc4106
  [CRYPTO] api: Show async type
  [CRYPTO] chainiv: Avoid lock spinning where possible
  [CRYPTO] seqiv: Add select AEAD in Kconfig
  [CRYPTO] scatterwalk: Handle zero nbytes in scatterwalk_map_and_copy
  [CRYPTO] null: Allow setkey on digest_null 
  ...
2008-01-25 08:38:25 -08:00
Kay Sievers af5ca3f4ec Driver core: change sysdev classes to use dynamic kobject names
All kobjects require a dynamically allocated name now. We no longer
need to keep track if the name is statically assigned, we can just
unconditionally free() all kobject names on cleanup.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:40 -08:00
Greg Kroah-Hartman 38a382ae5d Kobject: convert arch/* from kobject_unregister() to kobject_put()
There is no need for kobject_unregister() anymore, thanks to Kay's
kobject cleanup changes, so replace all instances of it with
kobject_put().


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:39 -08:00
Greg Kroah-Hartman f62ed9e33b firmware: change firmware_kset to firmware_kobj
There is no firmware "subsystem" it's just a directory in /sys that
other portions of the kernel want to hook into.  So make it a kobject
not a kset to help alivate anyone who tries to do some odd kset-like
things with this.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:23 -08:00
Greg Kroah-Hartman d91885bef2 kset: convert s390 ipl.c to use kset_create
Dynamically create the kset instead of declaring it statically.
This makes the kobject attributes now work properly that I broke in the
previous patch.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Michael Holzheu <holzheu@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Volker Sameske <sameske@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:21 -08:00
Greg Kroah-Hartman 9b949165bd kobject: convert s390 ipl.c to kobj_attr interface
This makes the code a bit simpler and and gets us one step closer to
deleting the deprecated subsys_attr code.

NOTE, this needs the next patch in the series in order to work properly.
This will build, but the sysfs files will not properly operate.

Thanks to Cornelia for the build fix on this patch.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Michael Holzheu <holzheu@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Volker Sameske <sameske@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:20 -08:00
Greg Kroah-Hartman 9b47770536 kobject: convert s390 hypervisor to use kobject_create
We don't need a kset here, a simple kobject will do just fine, so
dynamically create the kobject and use it.

Thanks to Cornelia for the build fix.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Michael Holzheu <holzheu@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:15 -08:00
Greg Kroah-Hartman 2d72fc00a1 kobject: convert /sys/hypervisor to use kobject_create
We don't need a kset here, a simple kobject will do just fine, so
dynamically create the kobject and use it.

We also rename hypervisor_subsys to hypervisor_kset to catch all users
of the variable.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:15 -08:00
Greg Kroah-Hartman 3514faca19 kobject: remove struct kobj_type from struct kset
We don't need a "default" ktype for a kset.  We should set this
explicitly every time for each kset.  This change is needed so that we
can make ksets dynamic, and cleans up one of the odd, undocumented
assumption that the kset/kobject/ktype model has.

This patch is based on a lot of help from Kay Sievers.

Nasty bug in the block code was found by Dave Young
<hidave.darkstar@gmail.com>

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:10 -08:00
Sebastian Siewior 2d74d405fc [CRYPTO] s390-aes: Use correct encrypt/decrypt function in fallback
crypto_blkcipher_decrypt is wrong because it does not care about
the IV.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:37 +11:00
Sebastian Siewior b0c3e75d85 [CRYPTO] aes_s390: Add fallback driver
Some CPUs support only 128 bit keys in HW. This patch adds SW fallback
support for the other keys which may be required. The generic algorithm
(and the block mode) must be availble in case of a fallback.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:27 +11:00
Sebastian Siewior 89e1265431 [CRYPTO] aes: Move common defines into a header file
This three defines are used in all AES related hardware.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:04 +11:00
Heiko Carstens 7af0d6f753 [S390] Make sure the restore psw masks are initialized.
In case of TRACE_IRQFLAGS the restore psw masks will not be
initialized if noexec is turned on. This will lead to an
immediate system crash.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-12-04 16:09:58 +01:00
Christian Borntraeger ab1809b4ed [S390] Fix compile error on 31bit without preemption
Commit b8e7a54cd0 introduced a compile
error if CONFIG_PREEMPT is not set:

arch/s390/kernel/built-in.o: In function `cleanup_io_leave_insn':
/space/kvm/arch/s390/kernel/entry.S:(.text+0xbfce): undefined reference to `preempt_schedule_irq'

This patch hides preempt_schedule_irq if CONFIG_PREEMPT is not set.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-12-04 16:09:58 +01:00
Heiko Carstens 06770a6e7d [S390] Add missing die_notifier() call to die().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:48 +01:00
Heiko Carstens a2cb07376e [S390] Fix memory detection.
Before we're getting short on memory detection fixes here is the next
one: if neither sclp nor diag260 report the storage size the detection
loop will return immediately without detecting anything. Fix this by
breaking the detection loop only if the memory end is known.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:48 +01:00
Heiko Carstens 677d762319 [S390] Dont overwrite lowcores on smp_send_stop().
Don't perform a sigp store-status-at-address on smp_send_stop().
It will overwrite the lowcores of other cpus and destroys valueable
debug informations.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:47 +01:00
Heiko Carstens b8e7a54cd0 [S390] Fix kernel preemption.
When returning from IRQ handling and TIF_NEED_RESCHED is set we must
call preempt_schedule_irq() instead of schedule().
Otherwise the BKL might be unlocked in schedule() and therfore
everything that relies on the BKL is broken.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:46 +01:00
Heiko Carstens 37e3a6ac5a [S390] appldata: remove unused binary sysctls.
Remove binary sysctls that never worked due to missing strategy functions.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:45 +01:00
Heiko Carstens 43ebbf119a [S390] cmm: remove unused binary sysctls.
Remove binary sysctls that never worked due to missing strategy functions.

Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:45 +01:00
Heiko Carstens 411788ea7f [S390] Fix irq tracing and lockdep_sys_exit calls.
Current support for TRACE_IRQFLAGS and lockdep_sys_exit is broken.
IRQ flag tracing is broken for program checks. Even worse is that
the newly introduced calls to lockdep_sys_exit are in the critical
section code which is not supposed to call any C functions. In
addition the checks if locks are still held are also done when
returning to kernel code which is broken as well.
Fix all this by disabling interrupts and machine checks at the
exit paths and then do the appropriate checks and calls.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:45 +01:00
Christian Borntraeger 7aa8dac7ac [S390] magic sysrq: check for in_atomic before doing an console_unblank
When doing an magic sysrq reboot on s390 the following bug message
appears:

SysRq : Resetting
BUG: sleeping function called from invalid context at include/asm/semaphore.h:61

in_atomic():1, irqs_disabled():0
07000000004002a8 000000000fe6bc48 0000000000000002 0000000000000000
       000000000fe6bce8 000000000fe6bc60 000000000fe6bc60 000000000012a79a
       0000000000000000 07000000004002a8 0000000000000006 0000000000000000
       0000000000000000 000000000fe6bc48 000000000000000d 000000000fe6bcb8
       00000000004000c8 0000000000103234 000000000fe6bc48 000000000fe6bc90
Call Trace:
(¬<00000000001031b2>| show_trace+0x12e/0x148)
 ¬<000000000011ffca>| __might_sleep+0x10a/0x118
 ¬<0000000000129fba>| acquire_console_sem+0x92/0xf4
 ¬<000000000012a2ca>| console_unblank+0xc2/0xc8
 ¬<0000000000107bb4>| machine_restart+0x54/0x6c
 ¬<000000000028e806>| sysrq_handle_reboot+0x26/0x30
 ¬<000000000028e52a>| __handle_sysrq+0xa6/0x180
 ¬<0000000000140134>| run_workqueue+0xcc/0x18c
 ¬<000000000014029a>| worker_thread+0xa6/0x108
 ¬<00000000001458e4>| kthread+0x64/0x9c
 ¬<0000000000106f0e>| kernel_thread_starter+0x6/0xc
 ¬<0000000000106f08>| kernel_thread_starter+0x0/0xc

The only reason for doing a console_unblank on s390 is to flush the
log buffer. We have to check for in_atomic before doing a
console_unblank as the console is otherwise filled with an unrelated
bug message.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:44 +01:00
Paul Mackerras fa13a5a1f2 sched: restore deterministic CPU accounting on powerpc
Since powerpc started using CONFIG_GENERIC_CLOCKEVENTS, the
deterministic CPU accounting (CONFIG_VIRT_CPU_ACCOUNTING) has been
broken on powerpc, because we end up counting user time twice: once in
timer_interrupt() and once in update_process_times().

This fixes the problem by pulling the code in update_process_times
that updates utime and stime into a separate function called
account_process_tick.  If CONFIG_VIRT_CPU_ACCOUNTING is not defined,
there is a version of account_process_tick in kernel/timer.c that
simply accounts a whole tick to either utime or stime as before.  If
CONFIG_VIRT_CPU_ACCOUNTING is defined, then arch code gets to
implement account_process_tick.

This also lets us simplify the s390 code a bit; it means that the s390
timer interrupt can now call update_process_times even when
CONFIG_VIRT_CPU_ACCOUNTING is turned on, and can just implement a
suitable account_process_tick().

account_process_tick() now takes the task_struct * as an argument.
Tested both with and without CONFIG_VIRT_CPU_ACCOUNTING.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-09 22:39:38 +01:00
Christian Borntraeger d2cb0e6ecb [S390] tod clock: announce clocksource as perfect
The Time of Day clock is the standard time source for s390. It is
- monotonic
- allows very fast reading
- architecture guarantees at least microsecond stepping
- available as part of the architecture

We should announce the rate of tod as 400 to be in sync with the
description found in clocksource.h:
"400-499:Perfect The ideal clocksource. A must-use where available."

This change will prefer tod over less reliable clock sources.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-05 11:10:18 +01:00