Commit Graph

57 Commits

Author SHA1 Message Date
Heiko Carstens
98c7b388af [S390] Get rid of memcpy gcc warning workaround.
Compile smp.o with -Wno-nonnull so gcc stops warning about memcpy
being used with a null parameter. Also remove the workaround code
and use a char * cast instead of a void * cast to do computations.

Cc: Bastian Blank <bastian@waldi.eu.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-03-05 12:37:17 +01:00
Heiko Carstens
591bb4f637 [S390] Initialize per cpu lowcores on cpu hotplug.
Just copy the first 512 read-only bytes of the current cpu lowcore if
a new cpu gets onlined. The rest is zeroed out and must be explicitly
initialized. Current code just copies the entire lowcore and
initializes the needed fields.
This should reveal bugs in future enhancements quite early.
Also when the lowcore of the first cpu is replaced this is now done
atomically (no interrupts, no machine checks).

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-19 15:29:33 +01:00
Heiko Carstens
2bc89b5ece [S390] Fix couple of section mismatches.
Fix couple of section mismatches. And since we touch the code
anyway change the IPL code to use C99 initializers.

Cc: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-05 16:50:56 +01:00
Heiko Carstens
37c5f719e7 [S390] Fix smp_call_function_mask semantics.
Make sure func isn't called on the local cpu just like on all other
architectures that implement this function.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-05 16:50:55 +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
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
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
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
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
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
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
69d39d6669 [S390] Rename "idle_time" attribute to "idle_time_us".
Seems that people prefer to have the unit encoded in the attribute
name. Also makes parsing easier.

Now we have:

# cat /sys/devices/system/cpu/cpu0/idle_time_us
131473592

instead of

# cat /sys/devices/system/cpu/cpu0/idle_time
131473592 us

Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-05 11:10:17 +01:00
Martin Schwidefsky
ba8a9229ab [S390] tlb flush fix.
The current tlb flushing code for page table entries violates the
s390 architecture in a small detail. The relevant section from the
principles of operation (SA22-7832-02 page 3-47):

   "A valid table entry must not be changed while it is attached
   to any CPU and may be used for translation by that CPU except to
   (1) invalidate the entry by using INVALIDATE PAGE TABLE ENTRY or
   INVALIDATE DAT TABLE ENTRY, (2) alter bits 56-63 of a page-table
   entry, or (3) make a change by means of a COMPARE AND SWAP AND
   PURGE instruction that purges the TLB."

That means if one thread of a multithreaded applciation uses a vma
while another thread does an unmap on it, the page table entries of
that vma needs to get removed with IPTE, IDTE or CSP. In some strange
and rare situations a cpu could check-stop (die) because a entry has
been pushed out of the TLB that is still needed to complete a
(milli-coded) instruction. I've never seen it happen with the current
code on any of the supported machines, so right now this is a
theoretical problem. But I want to fix it nevertheless, to avoid
headaches in the futures.

To get this implemented correctly without changing common code the
primitives ptep_get_and_clear, ptep_get_and_clear_full and
ptep_set_wrprotect need to use the IPTE instruction to invalidate the
pte before the new pte value gets stored. If IPTE is always used for
the three primitives three important operations will have a performace
hit: fork, mprotect and exit_mmap. Time for some workarounds:

* 1: ptep_get_and_clear_full is used in unmap_vmas to remove page
tables entries in a batched tlb gather operation. If the mmu_gather
context passed to unmap_vmas has been started with full_mm_flush==1
or if only one cpu is online or if the only user of a mm_struct is the
current process then the fullmm indication in the mmu_gather context is
set to one. All TLBs for mm_struct are flushed by the tlb_gather_mmu
call. No new TLBs can be created while the unmap is in progress. In
this case ptep_get_and_clear_full clears the ptes with a simple store.

* 2: ptep_get_and_clear is used in change_protection to clear the
ptes from the page tables before they are reentered with the new
access flags. At the end of the update flush_tlb_range clears the
remaining TLBs. In general the ptep_get_and_clear has to issue IPTE
for each pte and flush_tlb_range is a nop. But if there is only one
user of the mm_struct then ptep_get_and_clear uses simple stores
to do the update and flush_tlb_range will flush the TLBs.

* 3: Similar to 2, ptep_set_wrprotect is used in copy_page_range
for a fork to make all ptes of a cow mapping read-only. At the end of
of copy_page_range dup_mmap will flush the TLBs with a call to
flush_tlb_mm.  Check for mm->mm_users and if there is only one user
avoid using IPTE in ptep_set_wrprotect and let flush_tlb_mm clear the
TLBs.

Overall for single threaded programs the tlb flush code now performs
better, for multi threaded programs it is slightly worse. In particular
exit_mmap() now does a single IDTE for the mm and then just frees every
page cache reference and every page table page directly without a delay
over the mmu_gather structure.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 12:52:48 +02:00
Heiko Carstens
fae8b22d3e [S390] Add per-cpu idle time / idle count sysfs attributes.
Add two new sysfs entries per cpu: idle_count and idle_time.
idle_count contains the number of times a cpu went into idle state.
idle_time contains the time a cpu spent in idle state in microseconds.
This can be used e.g. by powertop to tell how often idle state is
entered and left.

# cat /sys/devices/system/cpu/cpu0/idle_count
504
# cat /sys/devices/system/cpu/cpu0/idle_time
469734037 us

Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 12:52:47 +02:00
Alexey Dobriyan
4e950f6f01 Remove fs.h from mm.h
Remove fs.h from mm.h. For this,
 1) Uninline vma_wants_writenotify(). It's pretty huge anyway.
 2) Add back fs.h or less bloated headers (err.h) to files that need it.

As result, on x86_64 allyesconfig, fs.h dependencies cut down from 3929 files
rebuilt down to 3444 (-12.3%).

Cross-compile tested without regressions on my two usual configs and (sigh):

alpha              arm-mx1ads        mips-bigsur          powerpc-ebony
alpha-allnoconfig  arm-neponset      mips-capcella        powerpc-g5
alpha-defconfig    arm-netwinder     mips-cobalt          powerpc-holly
alpha-up           arm-netx          mips-db1000          powerpc-iseries
arm                arm-ns9xxx        mips-db1100          powerpc-linkstation
arm-assabet        arm-omap_h2_1610  mips-db1200          powerpc-lite5200
arm-at91rm9200dk   arm-onearm        mips-db1500          powerpc-maple
arm-at91rm9200ek   arm-picotux200    mips-db1550          powerpc-mpc7448_hpc2
arm-at91sam9260ek  arm-pleb          mips-ddb5477         powerpc-mpc8272_ads
arm-at91sam9261ek  arm-pnx4008       mips-decstation      powerpc-mpc8313_rdb
arm-at91sam9263ek  arm-pxa255-idp    mips-e55             powerpc-mpc832x_mds
arm-at91sam9rlek   arm-realview      mips-emma2rh         powerpc-mpc832x_rdb
arm-ateb9200       arm-realview-smp  mips-excite          powerpc-mpc834x_itx
arm-badge4         arm-rpc           mips-fulong          powerpc-mpc834x_itxgp
arm-carmeva        arm-s3c2410       mips-ip22            powerpc-mpc834x_mds
arm-cerfcube       arm-shannon       mips-ip27            powerpc-mpc836x_mds
arm-clps7500       arm-shark         mips-ip32            powerpc-mpc8540_ads
arm-collie         arm-simpad        mips-jazz            powerpc-mpc8544_ds
arm-corgi          arm-spitz         mips-jmr3927         powerpc-mpc8560_ads
arm-csb337         arm-trizeps4      mips-malta           powerpc-mpc8568mds
arm-csb637         arm-versatile     mips-mipssim         powerpc-mpc85xx_cds
arm-ebsa110        i386              mips-mpc30x          powerpc-mpc8641_hpcn
arm-edb7211        i386-allnoconfig  mips-msp71xx         powerpc-mpc866_ads
arm-em_x270        i386-defconfig    mips-ocelot          powerpc-mpc885_ads
arm-ep93xx         i386-up           mips-pb1100          powerpc-pasemi
arm-footbridge     ia64              mips-pb1500          powerpc-pmac32
arm-fortunet       ia64-allnoconfig  mips-pb1550          powerpc-ppc64
arm-h3600          ia64-bigsur       mips-pnx8550-jbs     powerpc-prpmc2800
arm-h7201          ia64-defconfig    mips-pnx8550-stb810  powerpc-ps3
arm-h7202          ia64-gensparse    mips-qemu            powerpc-pseries
arm-hackkit        ia64-sim          mips-rbhma4200       powerpc-up
arm-integrator     ia64-sn2          mips-rbhma4500       s390
arm-iop13xx        ia64-tiger        mips-rm200           s390-allnoconfig
arm-iop32x         ia64-up           mips-sb1250-swarm    s390-defconfig
arm-iop33x         ia64-zx1          mips-sead            s390-up
arm-ixp2000        m68k              mips-tb0219          sparc
arm-ixp23xx        m68k-amiga        mips-tb0226          sparc-allnoconfig
arm-ixp4xx         m68k-apollo       mips-tb0287          sparc-defconfig
arm-jornada720     m68k-atari        mips-workpad         sparc-up
arm-kafa           m68k-bvme6000     mips-wrppmc          sparc64
arm-kb9202         m68k-hp300        mips-yosemite        sparc64-allnoconfig
arm-ks8695         m68k-mac          parisc               sparc64-defconfig
arm-lart           m68k-mvme147      parisc-allnoconfig   sparc64-up
arm-lpd270         m68k-mvme16x      parisc-defconfig     um-x86_64
arm-lpd7a400       m68k-q40          parisc-up            x86_64
arm-lpd7a404       m68k-sun3         powerpc              x86_64-allnoconfig
arm-lubbock        m68k-sun3x        powerpc-cell         x86_64-defconfig
arm-lusl7200       mips              powerpc-celleb       x86_64-up
arm-mainstone      mips-atlas        powerpc-chrp32

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-29 17:09:29 -07:00
Heiko Carstens
8da1aecde0 [S390] Improve __smp_call_function_map.
There is no need to disable bottom halves when holding call_lock. Also
this could imply that it is legal to call smp_call_function* from
bh context, which it is not.
Also test if func will be executed locally before disabling
and aterwards enabling interrupts again. It's not necessary to disable
and enable interrupts each time __smp_call_function_map gets called.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-27 12:29:17 +02:00
Heiko Carstens
3bb447fc8b [S390] Convert to smp_call_function_single.
smp_call_function_single now has the same semantics as s390's
smp_call_function_on. Therefore convert to the *single variant
and get rid of some architecture specific code.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-27 12:29:17 +02:00
Heiko Carstens
285f67227b [S390] smp: Merge smp_count_cpus() and smp_get_save_areas().
Merge smp_count_cpus() and smp_get_save_areas() so we save a loop over
all potentially present cpus.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-10 11:24:46 +02:00
Heiko Carstens
ea1f4eece9 [S390] Fix section annotations.
Use the __cpuinit instead of __devinit section annotations for code
that deals with cpu hotplug. In addition add some more annotations on
functions that have been left out so far.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-05-31 17:38:11 +02:00
Rafael J. Wysocki
8bb7844286 Add suspend-related notifications for CPU hotplug
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:56 -07:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Heiko Carstens
39ce010d38 [S390] Clean up smp code in preparation for some larger changes.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-04-27 16:01:47 +02:00
Heiko Carstens
2fc2d1e9ff [S390] Processor degradation notification.
Generate uevents for all cpus if cpu capability changes. This can
happen e.g. because the cpus are overheating. The cpu capability can
be read via /sys/devices/system/cpu/cpuN/capability.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-04-27 16:01:46 +02:00
Michael Holzheu
411ed32257 [S390] zfcpdump support.
s390 machines provide hardware support for creating Linux dumps on SCSI
disks. For creating a dump a special purpose dump Linux is used. The first
32 MB of memory are saved by the hardware before the dump Linux is
booted. Via an SCLP interface, the saved memory can be accessed from
Linux. This patch exports memory and registers of the crashed Linux to
userspace via a debugfs file. For more information refer to
Documentation/s390/zfcpdump.txt, which is included in this patch.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-04-27 16:01:44 +02:00
Heiko Carstens
25864162c1 [S390] smp: disable preemption in smp_call_function/smp_call_function_on
Avoid sprinkling a _lot_ of preempt_disable/preempt_enable pairs.
This would be necessary for e.g. the iucv driver. Also this way we
are more consistent with other architectures which disable
preemption at least for smp_call_function.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-05 23:35:41 +01:00
Michael Holzheu
46b05d2617 [S390] New header file ipl.h
Setup.h has been misused for ipl related stuff in the past. We now move
everything, which has to do with ipl and reipl to a new header file named
"ipl.h".

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-21 10:55:21 +01:00
Jan Glauber
63db6e8d41 [S390] smp_call_function cleanup
Introduce __smp_call_function_map which calls a function on all cpus
given with a cpumask_t. Use it to implement smp_call_function and
smp_call_function_on. Replace smp_ext_bitcall_others with smp_ext_bitcall
and a for_each_cpu_mask loop. Use a cpumask_t instead of an atomic_t for
cpu counting and print a warning if preempt is on in
__smp_call_function_map().

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-21 10:55:06 +01:00
Heiko Carstens
0ec67667ab [S390] smp_call_function/smp_call_function_on locking.
smp_call_function and smp_call_function_on share the same lock and
smp_call_function_on disables softirq's so it can be called from
softirq context as well. Hence smp_call_function muss disable
softirqs as well to avoid deadlocks.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-12 15:47:04 +01:00
Heiko Carstens
4d284cac76 [S390] Avoid excessive inlining.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:53 +01:00
Martin Schwidefsky
d54853ef8c [S390] ETR support.
This patch adds support for clock synchronization to an external time
reference (ETR). The external time reference sends an oscillator
signal and a synchronization signal every 2^20 microseconds to keep
the TOD clocks of all connected servers in sync. For availability
two ETR units can be connected to a machine. If the clock deviates
for more than the sync-check tolerance all cpus get a machine check
that indicates that the clock is out of sync. For the lovely details
how to get the clock back in sync see the code below.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:19 +01:00
Gerald Schaefer
c1821c2e97 [S390] noexec protection
This provides a noexec protection on s390 hardware. Our hardware does
not have any bits left in the pte for a hw noexec bit, so this is a
different approach using shadow page tables and a special addressing
mode that allows separate address spaces for code and data.

As a special feature of our "secondary-space" addressing mode, separate
page tables can be specified for the translation of data addresses
(storage operands) and instruction addresses. The shadow page table is
used for the instruction addresses and the standard page table for the
data addresses.
The shadow page table is linked to the standard page table by a pointer
in page->lru.next of the struct page corresponding to the page that
contains the standard page table (since page->private is not really
private with the pte_lock and the page table pages are not in the LRU
list).
Depending on the software bits of a pte, it is either inserted into
both page tables or just into the standard (data) page table. Pages of
a vma that does not have the VM_EXEC bit set get mapped only in the
data address space. Any try to execute code on such a page will cause a
page translation exception. The standard reaction to this is a SIGSEGV
with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn)
and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the
kernel to the signal stack frame. Unfortunately, the signal return
mechanism cannot be modified to use an SA_RESTORER because the
exception unwinding code depends on the system call opcode stored
behind the signal stack frame.

This feature requires that user space is executed in secondary-space
mode and the kernel in home-space mode, which means that the addressing
modes need to be switched and that the noexec protection only works
for user space.
After switching the addressing modes, we cannot use the mvcp/mvcs
instructions anymore to copy between kernel and user space. A new
mvcos instruction has been added to the z9 EC/BC hardware which allows
to copy between arbitrary address spaces, but on older hardware the
page tables need to be walked manually.

Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:17 +01:00
Heiko Carstens
2b67fc4606 [S390] Get rid of a lot of sparse warnings.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:16:47 +01:00
Heiko Carstens
6721f77810 [S390] Fix cpu hotplug (missing 'online' attribute).
72486f1f8f inverts the logic if an
'online' attribute in /sys/devices/system/cpu/cpuX should appear.
So we end up with no hotpluggable cpus at all...
Set the hotpluggable value to one to make sure the online
attribute appears again.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-01-09 10:18:44 +01:00
Heiko Carstens
29b08d2bae [S390] pfault code cleanup.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04 15:40:40 +01:00
Heiko Carstens
c6b5b847a7 [S390] cpu shutdown rework
Let one master cpu kill all other cpus instead of sending an external
interrupt to all other cpus so they can kill themselves.
Simplifies reipl/shutdown functions a lot.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04 15:40:33 +01:00
Heiko Carstens
5a489b9846 [S390] irq change build fixes.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-06 16:38:35 +02:00
Martin Schwidefsky
94c12cc7d1 [S390] Inline assembly cleanup.
Major cleanup of all s390 inline assemblies. They now have a common
coding style. Quite a few have been shortened, mainly by using register
asm variables. Use of the EX_TABLE macro helps  as well. The atomic ops,
bit ops and locking inlines new use the Q-constraint if a newer gcc
is used.  That results in slightly better code.

Thanks to Christian Borntraeger for proof reading the changes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 16:56:43 +02:00
Michael Holzheu
ff6b8ea68f [S390] ipl/dump on panic.
It is now possible to specify a ccw/fcp dump device which is used to
automatically create a system dump in case of a kernel panic. The dump
device can be configured under /sys/firmware/dump.
In addition it is now possible to specify a ccw/fcp device which is used
for the next reboot of Linux. The reipl device can be configured under
/sys/firmware/reipl.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20 15:58:49 +02:00
KAMEZAWA Hiroyuki
76b67ed9dc [PATCH] node hotplug: register cpu: remove node struct
With Goto-san's patch, we can add new pgdat/node at runtime.  I'm now
considering node-hot-add with cpu + memory on ACPI.

I found acpi container, which describes node, could evaluate cpu before
memory. This means cpu-hot-add occurs before memory hot add.

In most part, cpu-hot-add doesn't depend on node hot add.  But register_cpu(),
which creates symbolic link from node to cpu, requires that node should be
onlined before register_cpu().  When a node is onlined, its pgdat should be
there.

This patch-set holds off creating symbolic link from node to cpu
until node is onlined.

This removes node arguments from register_cpu().

Now, register_cpu() requires 'struct node' as its argument.  But the array of
struct node is now unified in driver/base/node.c now (By Goto's node hotplug
patch).  We can get struct node in generic way.  So, this argument is not
necessary now.

This patch also guarantees add cpu under node only when node is onlined.  It
is necessary for node-hot-add vs.  cpu-hot-add patch following this.

Moreover, register_cpu calculates cpu->node_id by cpu_to_node() without regard
to its 'struct node *root' argument.  This patch removes it.

Also modify callers of register_cpu()/unregister_cpu, whose args are changed
by register-cpu-remove-node-struct patch.

[Brice.Goglin@ens-lyon.org: fix it]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:37 -07:00
KAMEZAWA Hiroyuki
97db7fbfc7 [PATCH] for_each_possible_cpu: s390
for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00
Michael Ryan
699ff13f10 [PATCH] s390: cpu up retries
Retry starting of new cpu if sigp restart returns condition code 2 (busy).

Signed-off-by: Michael Ryan <ryan@funsoft.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:16 -08:00
Andrew Morton
394e3902c5 [PATCH] more for_each_cpu() conversions
When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all.  The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().

This patch is a kernel-wide sweep of all instances of NR_CPUS.  I found very
few instances of this bug, if any.  But the patch converts lots of open-coded
test to use the preferred helper macros.

Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:17 -08:00
Heiko Carstens
54330456b2 [PATCH] s390: smp initialization speed
The last changes that introduced the additional_cpus command line parameter
also introduced a regression regarding smp initialization speed.  In
smp_setup_cpu_possible_map() cpu_present_map is set to the same value as
cpu_possible_map.  Especially that means that bits in the present map will be
set for cpus that are not present.  This will cause a slow down in the initial
cpu_up() loop in smp_init() since trying to take cpus online that aren't
present takes a while.

Fix this by setting only bits for present cpus in cpu_present_map and set
cpu_present_map to cpu_possible_map in smp_cpus_done().

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:27 -08:00
Heiko Carstens
37a3302618 [PATCH] s390: possible_cpus parameter
Introduce possible_cpus command line option.  Hard sets the number of bits set
in cpu_possible_map.  Unlike the additional_cpus parameter this one guarantees
that num_possible_cpus() will stay constant even if the system gets rebooted
and a different number of cpus are present at startup.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:27 -08:00
Heiko Carstens
255acee706 [PATCH] s390: additional_cpus parameter
Introduce additional_cpus command line option.  By default no additional cpu
can be attached to the system anymore.  Only the cpus present at IPL time can
be switched on/off.  If it is desired that additional cpus can be attached to
the system the maximum number of additional cpus needs to be specified with
this option.

This change is necessary in order to limit the waste of per_cpu data
structures.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:26 -08:00
Heiko Carstens
9733e2407a [PATCH] s390: earlier initialization of cpu_possible_map
Initiliazing of cpu_possible_map was done in smp_prepare_cpus which is way too
late.  Therefore assign a static value to cpu_possible_map, since we don't
have access to max_cpus in setup_arch.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-11 21:41:12 -08:00
Al Viro
30af7120fe [PATCH] s390: task_stack_page()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:54 -08:00
Martin Schwidefsky
347a8dc3b8 [PATCH] s390: cleanup Kconfig
Sanitize some s390 Kconfig options.  We have ARCH_S390, ARCH_S390X,
ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT.  Replace these 6 options by
S390, 64BIT and COMPAT.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:53 -08:00
Martin Schwidefsky
973bd99375 [PATCH] s390: atomic primitives
Hugh Dickins <hugh@veritas.com>

Fix the broken atomic_cmpxchg primitive.  Add atomic_sub_and_test,
atomic64_sub_return, atomic64_sub_and_test, atomic64_cmpxchg,
atomic64_add_unless and atomic64_inc_not_zero.  Replace old style
atomic_compare_and_swap by atomic_cmpxchg.  Shorten the whole header by
defining most primitives with the two inline functions atomic_add_return and
atomic_sub_return.

In addition this patch contains the s390 related fixes of Hugh's "mm: fill
arch atomic64 gaps" patch.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:48 -08:00
Nick Piggin
5bfb5d690f [PATCH] sched: disable preempt in idle tasks
Run idle threads with preempt disabled.

Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?

Might fix the CPU hotplugging hang which Nigel Cunningham noted.

We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.

After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep.  The CPU will continue executing
previous idle and have no chance to call play_dead.

By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.

From: alexs <ashepard@u.washington.edu>

  PPC build fix

From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>

  MIPS build fix

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00