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2009-06-12[S390] ftrace: add dynamic ftrace supportHeiko Carstens
Dynamic ftrace support for s390. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] kprobes: use probe_kernel_writeHeiko Carstens
Use proble_kernel_write() to patch the kernel. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] maccess: arch specific probe_kernel_write() implementationHeiko Carstens
Add an s390 specific probe_kernel_write() function which allows to write to the kernel text segment even if write protection is enabled. This is implemented using the lra (load real address) and stura (store using real address) instructions. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] profile_tick called twiceMartin Schwidefsky
profile_tick is called twice for every clock comparator interrupt. The generic clock event code does it in tick_sched_timer and the s390 backend code in clock_comparator_work. That is one too many, remove the one in the arch backend code. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] vmalloc: add vmalloc kernel parameter supportHeiko Carstens
With the kernel parameter 'vmalloc=<size>' the size of the vmalloc area can be specified. This can be used to increase or decrease the size of the area. Works in the same way as on some other architectures. This can be useful for features which make excessive use of vmalloc and wouldn't work otherwise. The default sizes remain unchanged: 96MB for 31 bit kernels and 1GB for 64 bit kernels. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] uaccess: use might_fault() instead of might_sleep()Heiko Carstens
Adds more checking in case lockdep is turned on. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] secure computing arch backendHeiko Carstens
Enable secure computing on s390 as well. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] implement is_compat_taskHeiko Carstens
Implement is_compat_task and use it all over the place. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] add mini sclp driverHeiko Carstens
This adds a mini sclp device driver for very early use. The primary and probably only use will be to emit a message to the console if the cpu doesn't provide the minimum required capabilities to run the kernel. After printing the message a disabled wait will be loaded and the machine stops operating. Printing the message is also part of this patch. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] use facility list for cpu type safety checkMartin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] implement interrupt-enabling rwlocksHeiko Carstens
arch backend for f5f7eac41db827a47b2163330eecd7bb55ae9f12 "Allow rwlocks to re-enable interrupts". Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] merge cpu.h into cputime.hMartin Schwidefsky
All definition in cpu.h have to do with cputime accounting. Move them to cputime.h and remove the header file. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12[S390] vdso: kernel parameter syntaxMartin Schwidefsky
The syntax of the vdso kernel parameter is documented as vdso=[on|off]. The implementation uses vdso=[0|1], an invalid parameter string disables the vdso support. Fix the mismatch by adding vdso=[on|off] as additional parameter syntax. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-11asm-generic: rename page.h and uaccess.hArnd Bergmann
The current asm-generic/page.h only contains the get_order function, and asm-generic/uaccess.h only implements unaligned accesses. This renames the file to getorder.h and uaccess-unaligned.h to make room for new page.h and uaccess.h file that will be usable by all simple (e.g. nommu) architectures. Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-11asm-generic: rename atomic.h to atomic-long.hArnd Bergmann
The existing asm-generic/atomic.h only defines the atomic_long type. This renames it to atomic-long.h so we have a place to add a truly generic atomic.h that can be used on all non-SMP systems. Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Ingo Molnar <mingo@elte.hu>
2009-06-11asm-generic: introduce asm/bitsperlong.hArnd Bergmann
This provides a reliable way for asm-generic/types.h and other files to find out if it is running on a 32 or 64 bit platform. We cannot use CONFIG_64BIT for this in headers that are included from user space because CONFIG symbols are not available there. We also cannot do it inside of asm/types.h because some headers need the word size but cannot include types.h. The solution is to introduce a new header <asm/bitsperlong.h> that defines both __BITS_PER_LONG for user space and BITS_PER_LONG for usage in the kernel. The asm-generic version falls back to 32 bit unless the architecture overrides it, which I did for all 64 bit platforms. Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-11asm-generic: rename termios.h, signal.h and mman.hArnd Bergmann
The existing asm-generic versions are incomplete and included by some architectures. New architectures should be able to use a generic version, so rename the existing files and change all users, which lets us add the new files. Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-10KVM: s390: Verify memory in kvm runCarsten Otte
This check verifies that the guest we're trying to run in KVM_RUN has some memory assigned to it. It enters an endless exception loop if this is not the case. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: Sanity check on validity interceptCarsten Otte
This patch adds a sanity check for the content of the guest prefix register content before faulting in the cpu lowcore that it refers to. The guest might end up in an endless loop where SIE complains about missing lowcore with incorrect content of the prefix register without this fix. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: Unlink vcpu on destroy - v2Carsten Otte
This patch makes sure we do unlink a vcpu's sie control block from the system control area in kvm_arch_vcpu_destroy. This prevents illegal accesses to the sie control block from other virtual cpus after free. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: optimize float int lock: spin_lock_bh --> spin_lockChristian Borntraeger
The floating interrupt lock is only taken in process context. We can replace all spin_lock_bh with standard spin_lock calls. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: use hrtimer for clock wakeup from idle - v2Christian Borntraeger
This patch reworks the s390 clock comparator wakeup to hrtimer. The clock comparator is a per-cpu value that is compared against the TOD clock. If ckc <= TOD an external interrupt 1004 is triggered. Since the clock comparator and the TOD clock have a much higher resolution than jiffies we should use hrtimers to trigger the wakeup. This speeds up guest nanosleep for small values. Since hrtimers callbacks run in hard-irq context, I added a tasklet to do the actual work with enabled interrupts. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: s390: Fix memory slot versus run - v3Carsten Otte
This patch fixes an incorrectness in the kvm backend for s390. In case virtual cpus are being created before the corresponding memory slot is being registered, we need to update the sie control blocks for the virtual cpus. *updates in v3* In consideration of the s390 memslot constraints locking was changed to trylock. These locks should never be held, as vcpu's can't run without the single memslot we just assign when running this code. To ensure this never deadlocks in case other code changes the code uses trylocks and bail out if it can't get all locks. Additionally most of the discussed special conditions for s390 like only one memslot and no user_alloc are now checked for validity in kvm_arch_set_memory_region. Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10KVM: Fix interrupt unhalting a vcpu when it shouldn'tGleb Natapov
kvm_vcpu_block() unhalts vpu on an interrupt/timer without checking if interrupt window is actually opened. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-04-26s390: convert to use __HEAD and HEAD_TEXT macros.Tim Abbott
This has the consequence of changing the section name use for head code from ".text.head" to ".head.text". Since this commit changes all users in the architecture, this change should be harmless. Signed-off-by: Tim Abbott <tabbott@mit.edu> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-23[S390] update default configuration.Martin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-23[S390] /proc/stat idle field for idle cpusMartin Schwidefsky
The cpu idle field in the output of /proc/stat is too small for cpus that have been idle for more than a tick. Add the architecture hook arch_idle_time that allows to add the not accounted idle time of a sleeping cpu without waking the cpu. The s390 implementation of arch_idle_time uses the already existing s390_idle_data per_cpu variable to find the sleep time of a neighboring idle cpu. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-23[S390] appldata: avoid deadlock with appldata_memGerald Schaefer
The appldata_ops callbacks are called with a spin_lock held. But the appldata_mem callback then calls all_vm_events(), which calls get_online_cpus(), which might sleep. This possible deadlock is fixed by using a mutex instead of a spin_lock. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-23[S390] ipl: fix compile breakageHeiko Carstens
Fix this for !CONFIG_SMP: arch/s390/kernel/ipl.c: In function 'stop_run': arch/s390/kernel/ipl.c:1461: error: implicit declaration of function 'signal_processor' Reported-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-21clocksource: pass clocksource to read() callbackMagnus Damm
Pass clocksource pointer to the read() callback for clocksources. This allows us to share the callback between multiple instances. [hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods] [akpm@linux-foundation.org: cleanup] Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-20Separate out common fstatat code into vfs_fstatatOleg Drokin
This is a version incorporating Christoph's suggestion. Separate out common *fstatat functionality into a single function instead of duplicating it all over the code. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-14[S390] boot cputime accountingMartin Schwidefsky
Start the cpu time accounting very early to catch the cpu time spent for the initial kernel setup. To make the output of /proc/uptime match the sum of all cpu accounting values of the boot cpu reset xtime and wall_to_monotonic to sane values based on the TOD clock. The values set by timekeeping_init are off by up to a second. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] add read_persistent_clockMartin Schwidefsky
Add a read_persistent_clock function that does not just return 0. Since timekeeping_init calls the function before time_init has been called move reset_tod_clock to early.c to make sure that the TOD clock is running when read_persistent_clock is invoked. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] cpu hotplug and accounting valuesMartin Schwidefsky
Reset the cpu timer to the maximum value and correctly initialize the cpu accounting values in the lowcore when the cpu is started. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] fix idle time accountingMartin Schwidefsky
The steal time is calculated by subtracting the time the virtual cpu has been running on a physical cpu from the wall clock time. To make that work all wall time needs to be added to the steal time field first before the virtual cpu time is subtracted. The time between the last clock update and the load of the enabled wait psw needs to be added to the steal_time field as well to make the sum over all cpu accounting numbers match the wall clock. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] smp: fix cpu_possible_map initializationHeiko Carstens
The cpu_possible_map by default is initialized with all ones in s390. If the kernel paramert possible_cpus=<x> is passed the cpu_possible_map is supposed to have x bits set. However the current code just sets the x bits without clearing the NR_CPUS bits that were already set. So we end up with an unchanged map that has all bits set. To fix this just clear the map before setting any new bits. This broke with def6cfb70bab83c0094bc0cedd27c4eda563043e "[S390] cpumask: Use accessors code." Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] appldata: Use new mod_virt_timer_periodic() function.Gerald Schaefer
mod_virt_timer() was used to modify/add cpu timers for cpus that were set online. This resulted in a one-shot timer for every cpu that was newly added or previously set offline, instead of an interval timer, which broke the appldata vtime interval setup. To fix this, the new mod_virt_timer_periodic() function is used, which adds interval timers instead of one-shot timers. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] extend virtual timer interface by mod_virt_timer_periodicJan Glauber
In case mod_virt_timer is used to add a non pending timer the timer is always added as a one-shot timer. If mod_virt_timer is used for periodic timers they may therfore be degraded to one-shot timers. Add mod_virt_timer_periodic to the interface to allow safe re-programming of the interval value. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] stp synchronization retry timerMartin Schwidefsky
Add a timer that retries the clock synchronization via the server time protocol if there is a usable clock but the synchronization failed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] call nmi_enter/nmi_exit on machine checksHeiko Carstens
nmi_enter/nmi_exit includes the lockdep calls and various other calls which were missing so far. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] wire up preadv/pwritev system callsHeiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14[S390] s390: move machine flags to lowcoreChristian Ehrhardt
Currently the storage of the machine flags is a globally exported unsigned long long variable. By moving the storage location into the lowcore struct we allow assembler code to check machine_flags directly even without needing a register. Addtionally the lowcore and therefore the machine flags too will be in cache most of the time. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-09mutex: have non-spinning mutexes on s390 by defaultHeiko Carstens
Impact: performance regression fix for s390 The adaptive spinning mutexes will not always do what one would expect on virtualized architectures like s390. Especially the cpu_relax() loop in mutex_spin_on_owner might hurt if the mutex holding cpu has been scheduled away by the hypervisor. We would end up in a cpu_relax() loop when there is no chance that the state of the mutex changes until the target cpu has been scheduled again by the hypervisor. For that reason we should change the default behaviour to no-spin on s390. We do have an instruction which allows to yield the current cpu in favour of a different target cpu. Also we have an instruction which allows us to figure out if the target cpu is physically backed. However we need to do some performance tests until we can come up with a solution that will do the right thing on s390. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> LKML-Reference: <20090409184834.7a0df7b2@osiris.boeblingen.de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-03Merge branch 'ipi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: s390: remove arch specific smp_send_stop() panic: clean up kernel/panic.c panic, smp: provide smp_send_stop() wrapper on UP too panic: decrease oops_in_progress only after having done the panic generic-ipi: eliminate WARN_ON()s during oops/panic generic-ipi: cleanups generic-ipi: remove CSD_FLAG_WAIT generic-ipi: remove kmalloc() generic IPI: simplify barriers and locking
2009-04-02Allow rwlocks to re-enable interruptsRobin Holt
Pass the original flags to rwlock arch-code, so that it can re-enable interrupts if implemented for that architecture. Initially, make __raw_read_lock_flags and __raw_write_lock_flags stubs which just do the same thing as non-flags variants. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Robin Holt <holt@sgi.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <linux-arch@vger.kernel.org> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02Simplify copy_thread()Alexey Dobriyan
First argument unused since 2.3.11. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02generic debug pagealloc: build fixAkinobu Mita
This fixes a build failure with generic debug pagealloc: mm/debug-pagealloc.c: In function 'set_page_poison': mm/debug-pagealloc.c:8: error: 'struct page' has no member named 'debug_flags' mm/debug-pagealloc.c: In function 'clear_page_poison': mm/debug-pagealloc.c:13: error: 'struct page' has no member named 'debug_flags' mm/debug-pagealloc.c: In function 'page_poison': mm/debug-pagealloc.c:18: error: 'struct page' has no member named 'debug_flags' mm/debug-pagealloc.c: At top level: mm/debug-pagealloc.c:120: error: redefinition of 'kernel_map_pages' include/linux/mm.h:1278: error: previous definition of 'kernel_map_pages' was here mm/debug-pagealloc.c: In function 'kernel_map_pages': mm/debug-pagealloc.c:122: error: 'debug_pagealloc_enabled' undeclared (first use in this function) by fixing - debug_flags should be in struct page - define DEBUG_PAGEALLOC config option for all architectures Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6Linus Torvalds
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: [S390] cio: online_store - trigger recognition for boxed devices [S390] cio: disallow online setting of device in transient state [S390] cio: introduce notifier for boxed state [S390] cio: introduce ccw_device_schedule_sch_unregister [S390] cio: wake up on failed recognition [S390] fix hypfs build failure [PATCH] sysrq: include interrupt.h instead of irq.h
2009-04-01generic debug pageallocAkinobu Mita
CONFIG_DEBUG_PAGEALLOC is now supported by x86, powerpc, sparc64, and s390. This patch implements it for the rest of the architectures by filling the pages with poison byte patterns after free_pages() and verifying the poison patterns before alloc_pages(). This generic one cannot detect invalid page accesses immediately but invalid read access may cause invalid dereference by poisoned memory and invalid write access can be detected after a long delay. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-31[S390] cio: introduce notifier for boxed stateSebastian Ott
If a ccw device did not respond in time during internal io, we set it into boxed state. With this patch we have the following behaviour: * the ccw driver will get a notification if the device was online and goes into the boxed state * if the device was disconnected and got boxed nothing special is to be done (it will be handled in reprobing later) * if the device got boxed while initial sensing it will be unregistered Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>