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2013-10-31s390/vtime: correct idle time calculationMartin Schwidefsky
Use the ACCESS_ONCE macro for both accesses to idle->sequence in the loops to calculate the idle time. If only one access uses the macro, the compiler is free to cache the value for the second access which can cause endless loops. Cc: stable@vger.kernel.org # 3.6+ Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24s390: Remove zfcpdump NR_CPUS dependencyMichael Holzheu
Currently zfpcdump can only collect registers for up to CONFIG_NR_CPUS CPUss. This dependency is not necessary. So remove it by dynamically allocating the save area array. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24s390/uaccess: always run the kernel in home spaceMartin Schwidefsky
Simplify the uaccess code by removing the user_mode=home option. The kernel will now always run in the home space mode. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-09-07s390: make various functions static, add declarations to header filesHeiko Carstens
Make various functions static, add declarations to header files to fix a couple of sparse findings. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2013-07-14s390: delete __cpuinit usage from all s390 filesPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/s390 uses of the __cpuinit macros from all C files. Currently s390 does not have any __CPUINIT used in assembly files. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-26s390/smp: get rid of generic_smp_call_function_interruptHeiko Carstens
Since 9a46ad6d6 "smp: make smp_call_function_many() use logic similar to smp_call_function_single()" generic_smp_call_function_interrupt() is only an alias to generic_smp_call_function_single_interrupt(). So remove the superfluous variant. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-27s390/smp: lost IPIs on cpu hotplugHeiko Carstens
IPIs might be lost when a cpu gets brought offline: When stop_machine executes its state machine there is a race window for the state STOPMACHINE_DISABLE_IRQ where the to be brought offline cpu might already have irqs disabled but a different cpu still may have irqs enabled. If the enabled cpu receives an interrupt and as a result sends an IPI to the to be offlined cpu in its bottom halve context, the IPI won't be noticed before the cpu is offline. In fact the race window is much larger since there is no guarantee when an IPI will be received. To fix this check for enqueued but not yet received IPIs in the cpu_disable() path and call the respective handlers before the cpu is marked offline. Reported-by: Juergen Doelle <juergen.doelle@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-17s390/smp: fix cpu re-scan vs. cpu stateMartin Schwidefsky
The cpu-info array starts with a list of cpus in configured state, followed by the cpus in standby state. The comparison to decide which state a cpu has is incorrect, this causes configured cpus appear as standby cpus. The correct comparison is the index of the new cpu in the cpu-info array vs. the number of configured cpus. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-30Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP/hotplug changes from Ingo Molnar: "This is a pretty large, multi-arch series unifying and generalizing the various disjunct pieces of idle routines that architectures have historically copied from each other and have grown in random, wildly inconsistent and sometimes buggy directions: 101 files changed, 455 insertions(+), 1328 deletions(-) this went through a number of review and test iterations before it was committed, it was tested on various architectures, was exposed to linux-next for quite some time - nevertheless it might cause problems on architectures that don't read the mailing lists and don't regularly test linux-next. This cat herding excercise was motivated by the -rt kernel, and was brought to you by Thomas "the Whip" Gleixner." * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) idle: Remove GENERIC_IDLE_LOOP config switch um: Use generic idle loop ia64: Make sure interrupts enabled when we "safe_halt()" sparc: Use generic idle loop idle: Remove unused ARCH_HAS_DEFAULT_IDLE bfin: Fix typo in arch_cpu_idle() xtensa: Use generic idle loop x86: Use generic idle loop unicore: Use generic idle loop tile: Use generic idle loop tile: Enter idle with preemption disabled sh: Use generic idle loop score: Use generic idle loop s390: Use generic idle loop powerpc: Use generic idle loop parisc: Use generic idle loop openrisc: Use generic idle loop mn10300: Use generic idle loop mips: Use generic idle loop microblaze: Use generic idle loop ...
2013-04-26s390: lowcore stack pointer offsetsMartin Schwidefsky
Store the stack pointers in the lowcore for the kernel stack, the async stack and the panic stack with the offset required for the first user. This avoids an unnecessary add instruction on the system call path. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-08s390: Use generic idle loopThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Magnus Damm <magnus.damm@gmail.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Link: http://lkml.kernel.org/r/20130321215235.090816526@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-02-14s390/time: rename tod clock access functionsHeiko Carstens
Fix name clash with some common code device drivers and add "tod" to all tod clock access function names. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-01-08s390/irq: count cpu restart eventsHeiko Carstens
Count CPU Restart events and make them visible via /proc/interrupts. Every CPU hotplug (online) event will increase the per cpu counter. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-01-08s390/irq: remove split irq fields from /proc/statHeiko Carstens
Now that irq sum accounting for /proc/stat's "intr" line works again we have the oddity that the sum field (first field) contains only the sum of the second (external irqs) and third field (I/O interrupts). The reason for that is that these two fields are already sums of all other fields. So if we would sum up everything we would count every interrupt twice. This is broken since the split interrupt accounting was merged two years ago: 052ff461c8427629aee887ccc27478fc7373237c "[S390] irq: have detailed statistics for interrupt types". To fix this remove the split interrupt fields from /proc/stat's "intr" line again and only have them in /proc/interrupts. This restores the old behaviour, seems to be the only sane fix and mimics a behaviour from other architectures where /proc/interrupts also contains more than /proc/stat's "intr" line does. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-01-08s390/smp: fix section mismatch for smp_add_present_cpu()Heiko Carstens
Fixes this section mismatch: WARNING: vmlinux.o(.text+0x145e4): Section mismatch in reference from the function smp_add_present_cpu() to the function .cpuinit.text:register_cpu() The function smp_add_present_cpu() references the function __cpuinit register_cpu(). This is often because smp_add_present_cpu lacks a __cpuinit annotation or the annotation of register_cpu is wrong. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-01-03ARCH: drivers remove __dev* attributes.Greg Kroah-Hartman
This fixes up all of the smaller arches that had __dev* markings for their platform-specific drivers. CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Bob Liu <lliubbo@gmail.com> Cc: Srinivas Kandagatla <srinivas.kandagatla@st.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Myron Stowe <myron.stowe@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Thierry Reding <thierry.reding@avionic-design.de> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Cc: Mark Salter <msalter@redhat.com> Cc: Yong Zhang <yong.zhang0@gmail.com> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Jan Glauber <jang@linux.vnet.ibm.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26s390: add uninitialized_var() to suppress false positive compiler warningsHeiko Carstens
Get rid of these: arch/s390/kernel/smp.c:134:19: warning: ‘status’ may be used uninitialized in this function [-Wuninitialized] arch/s390/mm/pgtable.c:641:10: warning: ‘table’ may be used uninitialized in this function [-Wuninitialized] arch/s390/mm/pgtable.c:644:12: warning: ‘page’ may be used uninitialized in this function [-Wuninitialized] drivers/s390/cio/cio.c:1037:14: warning: ‘schid’ may be used uninitialized in this function [-Wuninitialized] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26s390/smp,topology: add polarization member to pcpu structHeiko Carstens
The cpu polarization member is the only per cpu state that is not part of the pcpu structure. So add it there and have everything in one place. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26s390/smp: avoid concurrent write to sigp status fieldHeiko Carstens
When a sigp instruction is issued it may store a status. This status is currently stored in a per cpu field of the target cpu. If multiple cpus issue a sigp instruction with the same target cpu and a status is stored the result is not necessarily as expected. Currently this is not an issue: - on cpu hotplug no sigps, except "restart" and "sense" are sent to the target cpu. - on external call we don't look at the status if it is stored - on sense running the condition code "status stored" is sufficient to tell if a cpu is running or not Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26s390/cpu hotplug: mask out CPU_TASKS_FROZEN in cu hotplug notifiersHeiko Carstens
Unify all our cpu hotplug notifiers to mask out the CPU_TASKS_FROZEN bit, so we don't have to add all the *_FROZEN variant cases to the notifiers. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-09-26s390/cpu hotplug: use hotcpu_notifier() instead of register_cpu_notifier()Heiko Carstens
Saves a couple of lines of code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-07-24Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 changes from Martin Schwidefsky: "No new functions, a few changes to make the code more robust, some cleanups and bug fixes." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (21 commits) s390/vtimer: rework virtual timer interface s390/dis: Add the servc instruction to the disassembler. s390/comments: unify copyright messages and remove file names s390/lgr: Add init check to lgr_info_log() s390/cpu init: use __get_cpu_var instead of per_cpu s390/idle: reduce size of s390_idle_data structure s390/idle: fix sequence handling vs cpu hotplug s390/ap: resend enable adapter interrupt request. s390/hypfs: Add missing get_next_ino() s390/dasd: add shutdown action s390/ipl: Fix ipib handling for "dumpreipl" shutdown action s390/smp: make absolute lowcore / cpu restart parameter accesses more robust s390/vmlogrdr: cleanup driver attribute usage s390/vmlogrdr: cleanup device attribute usage s390/ccwgroup: remove unused ccwgroup_device member s390/cio/chp: cleanup attribute usage s390/sigp: use sigp order code defines in assembly code s390/smp: use sigp cpu status definitions s390/smp/kvm: unifiy sigp definitions s390/smp: remove redundant check ...
2012-07-20s390/vtimer: rework virtual timer interfaceMartin Schwidefsky
The current virtual timer interface is inherently per-cpu and hard to use. The sole user of the interface is appldata which uses it to execute a function after a specific amount of cputime has been used over all cpus. Rework the virtual timer interface to hook into the cputime accounting. This makes the interface independent from the CPU timer interrupts, and makes the virtual timers global as opposed to per-cpu. Overall the code is greatly simplified. The downside is that the accuracy is not as good as the original implementation, but it is still good enough for appldata. Reviewed-by: Jan Glauber <jang@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-07-20s390/comments: unify copyright messages and remove file namesHeiko Carstens
Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-17s390/idle: fix sequence handling vs cpu hotplugHeiko Carstens
The s390 idle accounting code uses a sequence counter which gets used when the per cpu idle statistics get updated and read. One assumption on read access is that only when the sequence counter is even and did not change while reading all values the result is valid. On cpu hotplug however the per cpu data structure gets initialized via a cpu hotplug notifier on CPU_ONLINE. CPU_ONLINE however is too late, since the onlined cpu is already running and might access the per cpu data. Worst case is that the data structure gets initialized while an idle thread is updating its idle statistics. This will result in an uneven sequence counter after an update. As a result user space tools like top, which access /proc/stat in order to get idle stats, will busy loop waiting for the sequence counter to become even again, which will never happen until the queried cpu will update its idle statistics again. And even then the sequence counter will only have an even value for a couple of cpu cycles. Fix this by moving the initialization of the per cpu idle statistics to cpu_init(). I prefer that solution in favor of changing the notifier to CPU_UP_PREPARE, which would be a different solution to the problem. Cc: stable@vger.kernel.org Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-06-14s390/smp: make absolute lowcore / cpu restart parameter accesses more robustHeiko Carstens
Setting the cpu restart parameters is done in three different fashions: - directly setting the four parameters individually - copying the four parameters with memcpy (using 4 * sizeof(long)) - copying the four parameters using a private structure In addition code in entry*.S relies on a certain order of the restart members of struct _lowcore. Make all of this more robust to future changes by adding a mem_absolute_assign(dest, val) define, which assigns val to dest using absolute addressing mode. Also the load multiple instructions in entry*.S have been split into separate load instruction so the order of the struct _lowcore members doesn't matter anymore. In addition move the prototypes of memcpy_real/absolute from uaccess.h to processor.h. These memcpy* variants are not related to uaccess at all. string.h doesn't seem to match as well, so lets use processor.h. Also replace the eight byte array in struct _lowcore which represents a misaliged u64 with a u64. The compiler will always create code that handles the misaligned u64 correctly. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-06-05S390: Smp: remove call to ipi_call_lock()/ipi_call_unlock()Yong Zhang
ipi_call_lock/unlock() lock resp. unlock call_function.lock. This lock protects only the call_function data structure itself, but it's completely unrelated to cpu_online_mask. The mask to which the IPIs are sent is calculated before call_function.lock is taken in smp_call_function_many(), so the locking around set_cpu_online() is pointless and can be removed. [ tglx: Massaged changelog ] Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Cc: ralf@linux-mips.org Cc: sshtylyov@mvista.com Cc: david.daney@cavium.com Cc: nikunj@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: axboe@kernel.dk Cc: peterz@infradead.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Link: http://lkml.kernel.org/r/1338275765-3217-5-git-send-email-yong.zhang0@gmail.com Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-06-05s390/sigp: use sigp order code defines in assembly codeHeiko Carstens
Use sigp order code defines in assembly code as well. With this change all places that use sigp constants should have been converted to use self describing defines instead of directly using constants. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-06-05s390/smp: use sigp cpu status definitionsHeiko Carstens
We got them from the kvm code, so let's use them. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-06-05s390/smp/kvm: unifiy sigp definitionsHeiko Carstens
The smp and the kvm code have different defines for the sigp order codes. Let's just have a single place where these are defined. Also move the sigp condition code and sigp cpu status bits to the new sigp.h header file. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-06-05s390/smp: remove redundant checkHeiko Carstens
condition code "status stored" for sigp sense running always implies that only the "not running" status bit is set. Therefore no need to check if it is set. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-05-30s390/cpu: remove cpu "capabilities" sysfs attributeHeiko Carstens
It has been a big mistage to add the capabilities attribute to the cpus in sysfs: First the attribute only contains the cpu capability of primary cpus, which however is not necessarily (or better: unlikely) the type of cpu the kernel runs on, which is typically an IFL. In addition all information that is necessary is available in /proc/sysinfo already. So this attribute partially duplicated informations. So programs should look into the sysinfo file to retrieve all informations they are interested in. Since with this kernel release also the powersavings cpu attributes are removed this seems to be a good opportunity to remove another broken interface. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-05-30s390/kernel: Fix smp_call_ipl_cpu() for offline CPUsMichael Holzheu
If the IPL CPU is offline, currently the pcpu_delegate() function used by smp_call_ipl_cpu() does not work because pcpu_delegate() modifies the lowcore of the target CPU. In case of an offline IPL CPU currently the prefix register is zero but pcpu->lowcore still points to the old prefix page. Therefore the lowcore changes done by pcpu_delegate() have no effect. With this fix pcpu_delegate() now uses memcpy_absolute() and therefore also prepares the absolute zero lowcore if the target CPU has prefix register zero. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-05-23s390/kernel: Remove OS info init function call and diag 308 for kdumpMichael Holzheu
Because of a design change for stand-alone kdump the function that was done by the OS info init function is moved to the boot loader code. This has two implications that are implemented by this patch: a) The OS info init function is no longer called by the kernel b) The diag 308 subcode 1 reset is no longer done by the kdump boot code. This is necessary because otherwise the operation that is done now by the boot loader would be reversed. For the normal kexec based kdump mechansim the reset is already done by the kdump trigger code (e.g. panic or PSW restart). Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-05-21Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug cleanups from Thomas Gleixner: "This series is merily a cleanup of code copied around in arch/* and not changing any of the real cpu hotplug horrors yet. I wish I'd had something more substantial for 3.5, but I underestimated the lurking horror..." Fix up trivial conflicts in arch/{arm,sparc,x86}/Kconfig and arch/sparc/include/asm/thread_info_32.h * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits) um: Remove leftover declaration of alloc_task_struct_node() task_allocator: Use config switches instead of magic defines sparc: Use common threadinfo allocator score: Use common threadinfo allocator sh-use-common-threadinfo-allocator mn10300: Use common threadinfo allocator powerpc: Use common threadinfo allocator mips: Use common threadinfo allocator hexagon: Use common threadinfo allocator m32r: Use common threadinfo allocator frv: Use common threadinfo allocator cris: Use common threadinfo allocator x86: Use common threadinfo allocator c6x: Use common threadinfo allocator fork: Provide kmemcache based thread_info allocator tile: Use common threadinfo allocator fork: Provide weak arch_release_[task_struct|thread_info] functions fork: Move thread info gfp flags to header fork: Remove the weak insanity sh: Remove cpu_idle_wait() ...
2012-05-16s390/smp: get rid of compile warningHeiko Carstens
Add missing #ifdep CONFIG_HOTPLUG_CPU to get rid of this one: arch/s390/kernel/smp.c:229:13: warning: 'pcpu_free_lowcore' defined but not used [-Wunused-function] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-04-26s390: Use generic idle thread allocationThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Link: http://lkml.kernel.org/r/20120420124557.652574928@linutronix.de
2012-04-26smp: Add task_struct argument to __cpu_up()Thomas Gleixner
Preparatory patch to make the idle thread allocation for secondary cpus generic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Howells <dhowells@redhat.com> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David S. Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Richard Weinberger <richard@nod.at> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
2012-03-30[S390] Fix build errors (fallout from system.h disintegration)Heiko Carstens
Signed-off-by: Heiko Carstens <h.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 patches from Martin Schwidefsky: "The biggest patch is the rework of the smp code, something I wanted to do for some time. There are some patches for our various dump methods and one new thing: z/VM LGR detection. LGR stands for linux-guest- relocation and is the guest migration feature of z/VM. For debugging purposes we keep a log of the systems where a specific guest has lived." Fix up trivial conflict in arch/s390/kernel/smp.c due to the scheduler cleanup having removed some code next to removed s390 code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: [S390] kernel: Pass correct stack for smp_call_ipl_cpu() [S390] Ensure that vmcore_info pointer is never accessed directly [S390] dasd: prevent validate server for offline devices [S390] Remove monolithic build option for zcrypt driver. [S390] stack dump: fix indentation in output [S390] kernel: Add OS info memory interface [S390] Use block_sigmask() [S390] kernel: Add z/VM LGR detection [S390] irq: external interrupt code passing [S390] irq: set __ARCH_IRQ_EXIT_IRQS_DISABLED [S390] zfcpdump: Implement async sdias event processing [S390] Use copy_to_absolute_zero() instead of "stura/sturg" [S390] rework idle code [S390] rework smp code [S390] rename lowcore field [S390] Fix gcc 4.6.0 compile warning
2012-03-13[S390] kernel: Pass correct stack for smp_call_ipl_cpu()Michael Holzheu
Currently pcpu_devices->panic_stack is passed to pcpu_delegate() in smp_call_ipl_cpu(). This is wrong because pcpu_delegate() expects the bottom (high address) of the stack and pcpu_devices->panic_stack points to the top (low address). We now pass the bottom of the stack which is pcpu_devices->panic_stack + PAGE_SIZE. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-12sched: Cleanup cpu_active madnessPeter Zijlstra
Stepan found: CPU0 CPUn _cpu_up() __cpu_up() boostrap() notify_cpu_starting() set_cpu_online() while (!cpu_active()) cpu_relax() <PREEMPT-out> smp_call_function(.wait=1) /* we find cpu_online() is true */ arch_send_call_function_ipi_mask() /* wait-forever-more */ <PREEMPT-in> local_irq_enable() cpu_notify(CPU_ONLINE) sched_cpu_active() set_cpu_active() Now the purpose of cpu_active is mostly with bringing down a cpu, where we mark it !active to avoid the load-balancer from moving tasks to it while we tear down the cpu. This is required because we only update the sched_domain tree after we brought the cpu-down. And this is needed so that some tasks can still run while we bring it down, we just don't want new tasks to appear. On cpu-up however the sched_domain tree doesn't yet include the new cpu, so its invisible to the load-balancer, regardless of the active state. So instead of setting the active state after we boot the new cpu (and consequently having to wait for it before enabling interrupts) set the cpu active before we set it online and avoid the whole mess. Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-11[S390] kernel: Add OS info memory interfaceMichael Holzheu
In order to allow kdump based stand-alone dump, some information has to be passed from the old kernel to the new dump kernel. This is done via a the struct "os_info" that contains the following fields: * crashkernel base and size * reipl block * vmcoreinfo * init function A pointer to os_info is stored at a well known storage location and the whole structure as well as all fields are secured with checksums. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11[S390] kernel: Add z/VM LGR detectionMichael Holzheu
Currently the following mechanisms are available to move active Linux on System z instances between machines: * z/VM 6.2 SSI (Single System Image) * Suspend/resume For moving Linux instances in this patch the term LGR (Linux Guest Relocation) is used. Because such an operation is critical, it should be detectable from Linux. With this patch for both, a live system and a kernel dump, the information about LGRs is accessible. To identify a guest, stsi and stfle data is used. A new function lgr_info_log() compares the current data (lgr_info_cur) with the last recorded one (lgr_info_last). In case the two data sets differ, lgr_info_cur is logged to the "lgr" s390dbf. The following trigger points call lgr_info_log(): * panic * die * kdump * LGR timer * PSW restart * QDIO recovery * resume This patch also changes the s390dbf hex_ascii view. Now only printable ASCII characters are shown. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11[S390] irq: external interrupt code passingHeiko Carstens
The external interrupt handlers have a parameter called ext_int_code. Besides the name this paramter does not only contain the ext_int_code but in addition also the "cpu address" (POP) which caused the external interrupt. To make the code a bit more obvious pass a struct instead so the called function can easily distinguish between external interrupt code and cpu address. The cpu address field however is named "subcode" since some external interrupt sources do not pass a cpu address but a different parameter (or none at all). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11[S390] rework idle codeMartin Schwidefsky
Whenever the cpu loads an enabled wait PSW it will appear as idle to the underlying host system. The code in default_idle calls vtime_stop_cpu which does the necessary voodoo to get the cpu time accounting right. The udelay code just loads an enabled wait PSW. To correct this rework the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts to entry[64].S, vtime_stop_cpu can now be called from anywhere and vtime_start_cpu is gone. The correction of the cpu time during wakeup from an enabled wait PSW is done with a critical section in entry[64].S. As vtime_start_cpu is gone, s390_idle_check can be removed as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11[S390] rework smp codeMartin Schwidefsky
Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-01-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits) [S390] disassembler: mark exception causing instructions [S390] Enable exception traces by default [S390] return address of compat signals [S390] sysctl: get rid of dead declaration [S390] dasd: fix fixpoint divide exception in define_extent [S390] dasd: add sanity check to detect path connection error [S390] qdio: fix kernel panic for zfcp 31-bit [S390] Add s390x description to Documentation/kdump/kdump.txt [S390] Add VMCOREINFO_SYMBOL(high_memory) to vmcoreinfo [S390] dasd: fix expiration handling for recovery requests [S390] outstanding interrupts vs. smp_send_stop [S390] ipc: call generic sys_ipc demultiplexer [S390] zcrypt: Fix error return codes. [S390] zcrypt: Rework length parameter checking. [S390] cleanup trap handling [S390] Remove Kerntypes leftovers [S390] topology: increase poll frequency if change is anticipated [S390] entry[64].S improvements [S390] make arch/s390 subdirectories depend on config option [S390] kvm: move cmf host id constant out of lowcore ... Fix up conflicts in arch/s390/kernel/{smp.c,topology.c} due to the sysdev removal clashing with "topology: get rid of ifdefs" which moved some of that code around.
2011-12-27[S390] outstanding interrupts vs. smp_send_stopMartin Schwidefsky
The panic function will first print the panic message to the console, then stop additional cpus with smp_send_stop and finally call the function on the panic notifier list. In case of an I/O based console the panic message will cause I/O to be started and a function on the panic notifier list will wait for the completion of the I/O. That does not work if an I/O completion interrupt has already been delivered to a cpu that is then stopped by smp_send_stop. To break this cyclic dependency add code to smp_send_stop that gives the additional cpu the opportunity to complete outstanding interrupts. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-27[S390] topology: increase poll frequency if change is anticipatedHeiko Carstens
Increase cpu topology change poll frequency if a change is anticipated. Otherwise a user might be a bit confused to have to wait up to a minute in order to see a change this should be visible immediatly. However there is no guarantee that the change will happen during the time frame the poll frequency is increased. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>