Commit Graph

1868 Commits

Author SHA1 Message Date
Heiko Carstens
77ec8a5451 s390/stacktrace: use nosched instead of savesched parameter
Use the inversed "nosched" logic like all other architectures.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-23 08:56:17 +01:00
Martin Schwidefsky
342300cc9c s390/compat: correct restore of high gprs on signal return
git commit 8070361799
"s390: add support for vector extension"
broke 31-bit compat processes in regard to signal handling.

The restore_sigregs_ext32() function is used to restore the additional
elements from the user space signal frame. Among the additional elements
are the upper registers halves for 64-bit register support for 31-bit
processes. The copy_from_user that is used to retrieve the high-gprs
array from the user stack uses an incorrect length, 8 bytes instead of
64 bytes. This causes incorrect upper register halves to get loaded.

Cc: stable@vger.kernel.org # 3.8+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-22 09:29:35 +01:00
Heiko Carstens
f6c9b16023 s390/diag: avoid lockdep recursion
The diagnose tracer will indirectly call back into the lockdep code
when lockdep does not expect it (arch_spinlock). This causes lockdep
to disable itself and therefore we don't have a working lock
dependency validator anymore.

This patch effectively disables tracing of diag 0x9c and 0x44 if
lockdep is enabled.  If however lockdep is enabled spinlocks are
mainly implemented using a trylock variant, which will not issue any
diag 0x9c or 0x44. So this change has hardly any effect on tracing
except when arch_spinlock and friends are explicitly used.

Reported-and-Tested-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-11 13:05:56 +01:00
Heiko Carstens
1f8cbb9c83 s390/perf_event: fix address range for asynchronous stack
git commit dc7ee00d47 ("s390: lowcore stack pointer offsets")
introduced a regression in regard to perf_callchain_kernel(). The
stack pointer for the asynchronous stack in the lowcore now has an
additional offset applied. This offset needs to be taken into account
in the calculation for the low and high address for the stack.

This bug was already partially fixed with 9cc5c206d9
("s390/dumpstack: fix address ranges for asynchronous and panic
stack"). This patch fixes it also for the perf_event code.

Fixes: dc7ee00d47 ("s390: lowcore stack pointer offsets")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-10 09:25:22 +01:00
Pratyush Anand
e0115875c0 s390/stacktrace: add save_stack_trace_regs()
Implement save_stack_trace_regs, so that a stack trace of a kprobe
event can be obtained.

Without this we see following warning:
"save_stack_trace_regs() not implemented yet."
when we execute:
echo stacktrace > /sys/kernel/debug/tracing/trace_options
echo "p kfree" >> /sys/kernel/debug/tracing/kprobe_events
echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable

Reported-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Pratyush Anand <panand@redhat.com>
[heiko.carstens@de.ibm.com]: changed patch to use __save_stack_trace()
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-10 09:25:22 +01:00
Heiko Carstens
66adce8f1f s390/stacktrace: save full stack traces
save_stack_trace() only saves the stack trace of the current context
(interrupt or process context). This is different to what other
architectures like x86 do, which save the full stack trace across
different contexts.

Also extract a __save_stack_trace() helper function which will be used
by a follow on patch.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-10 09:25:21 +01:00
Heiko Carstens
f6331aaccb s390/stacktrace: add missing end marker
save_stack_trace() did not write the ULONG_MAX end marker if there is
enough space left. So simply follow x86 and arm64.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-10 09:25:21 +01:00
Heiko Carstens
9900c48c46 s390/stacktrace: fix address ranges for asynchronous and panic stack
git commit dc7ee00d47 ("s390: lowcore stack pointer offsets")
introduced a regression in regard to save_stack_trace(). The stack
pointer for the asynchronous and the panic stack in the lowcore now
have an additional offset applied to them. This offset needs to be
taken into account in the calculation for the low and high address for
the stacks.

This bug was already partially fixed with 9cc5c206d9
("s390/dumpstack: fix address ranges for asynchronous and panic
stack"). This patch fixes it also for the stacktrace code.

Fixes: dc7ee00d47 ("s390: lowcore stack pointer offsets")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-10 09:25:20 +01:00
Heiko Carstens
665ca9187c s390/stacktrace: fix save_stack_trace_tsk() for current task
The function save_stack_trace_tsk() did not consider that it can be
used for tsk == current, for which the current stack pointer obviously
cannot be found in the thread structure.

Fix this and get the stack pointer with an inline assembly.

This fixes e.g. the output of "cat /proc/self/stack".

Before:
[<0000000000000000>]           (null)
[<ffffffffffffffff>] 0xffffffffffffffff

After:
[<000000000011b3ee>] save_stack_trace_tsk+0x56/0x98
[<0000000000366cde>] proc_pid_stack+0xae/0x108
[<00000000003636f0>] proc_single_show+0x70/0xc0
[<0000000000311fbc>] seq_read+0xcc/0x448
[<00000000002e7716>] __vfs_read+0x36/0x100
[<00000000002e872e>] vfs_read+0x76/0x130
[<00000000002e975e>] SyS_read+0x66/0xd8
[<000000000089490e>] system_call+0xd6/0x264
[<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-10 09:25:20 +01:00
Andrey Ryabinin
06bea3dbfe locking/lockdep: Eliminate lockdep_init()
Lockdep is initialized at compile time now.  Get rid of lockdep_init().

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Krinkin <krinkin.m.u@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Cc: mm-commits@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-09 12:03:25 +01:00
Toshi Kani
35d98e93fe arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM
Set IORESOURCE_SYSTEM_RAM in flags of resource ranges with
"System RAM", "Kernel code", "Kernel data", and "Kernel bss".

Note that:

 - IORESOURCE_SYSRAM (i.e. modifier bit) is set in flags when
   IORESOURCE_MEM is already set. IORESOURCE_SYSTEM_RAM is defined
   as (IORESOURCE_MEM|IORESOURCE_SYSRAM).

 - Some archs do not set 'flags' for children nodes, such as
   "Kernel code".  This patch does not change 'flags' in this
   case.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@linux-mips.org
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1453841853-11383-7-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30 09:49:57 +01:00
Heiko Carstens
9cb1ccecb6 s390: remove all usages of PSW_ADDR_INSN
Yet another leftover from the 31 bit era. The usual operation
"y = x & PSW_ADDR_INSN" with the PSW_ADDR_INSN mask is a nop for
CONFIG_64BIT.

Therefore remove all usages and hope the code is a bit less confusing.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2016-01-19 12:14:03 +01:00
Heiko Carstens
fecc868a66 s390: remove all usages of PSW_ADDR_AMODE
This is a leftover from the 31 bit area. For CONFIG_64BIT the usual
operation "y = x | PSW_ADDR_AMODE" is a nop. Therefore remove all
usages of PSW_ADDR_AMODE and make the code a bit less confusing.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2016-01-19 12:14:02 +01:00
Heiko Carstens
696aafd369 s390: wire up copy_file_range syscall
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-19 12:14:02 +01:00
Heiko Carstens
cd17e153af s390: remove superfluous memblock_alloc() return value checks
memblock_alloc() and memblock_alloc_base() will panic on their own if
they can't find free memory. Therefore remove some pointless checks.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-19 12:14:02 +01:00
Linus Torvalds
0f0836b7eb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching updates from Jiri Kosina:

 - RO/NX attribute fixes for patch module relocations from Josh
   Poimboeuf.  As part of this effort, module.c has been cleaned up as
   well and livepatching is piggy-backing on this cleanup.  Rusty is OK
   with this whole lot going through livepatching tree.

 - symbol disambiguation support from Chris J Arges.  That series is
   also

        Reviewed-by: Miroslav Benes <mbenes@suse.cz>

   but this came in only after I've alredy pushed out.  Didn't want to
   rebase because of that, hence I am mentioning it here.

 - symbol lookup fix from Miroslav Benes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Cleanup module page permission changes
  module: keep percpu symbols in module's symtab
  module: clean up RO/NX handling.
  module: use a structure to encapsulate layout.
  gcov: use within_module() helper.
  module: Use the same logic for setting and unsetting RO/NX
  livepatch: function,sympos scheme in livepatch sysfs directory
  livepatch: add sympos as disambiguator field to klp_reloc
  livepatch: add old_sympos as disambiguator field to klp_func
2016-01-14 16:38:02 -08:00
Linus Torvalds
cbd88cd4c0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "Among the traditional bug fixes and cleanups are some improvements:

   - A tool to generated the facility lists, generating the bit fields
     by hand has been a source of bugs in the past

   - The spinlock loop is reordered to avoid bursts of hypervisor calls

   - Add support for the open-for-business interface to the service
     element

   - The get_cpu call is added to the vdso

   - A set of tracepoints is defined for the common I/O layer

   - The deprecated sclp_cpi module is removed

   - Update default configuration"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits)
  s390/sclp: fix possible control register corruption
  s390: fix normalization bug in exception table sorting
  s390/configs: update default configurations
  s390/vdso: optimize getcpu system call
  s390: drop smp_mb in vdso_init
  s390: rename struct _lowcore to struct lowcore
  s390/mem_detect: use unsigned longs
  s390/ptrace: get rid of long longs in psw_bits
  s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields
  s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK
  s390/Kconfig: remove pointless 64 bit dependencies
  s390/dasd: fix failfast for disconnected devices
  s390/con3270: testing return kzalloc retval
  s390/hmcdrv: constify hmcdrv_ftp_ops structs
  s390/cio: add NULL test
  s390/cio: Change I/O instructions from inline to normal functions
  s390/cio: Introduce common I/O layer tracepoints
  s390/cio: Consolidate inline assemblies and related data definitions
  s390/cio: Fix incorrect xsch opcode specification
  s390/cio: Remove unused inline assemblies
  ...
2016-01-13 13:16:16 -08:00
Linus Torvalds
1baa5efbeb * s390: Support for runtime instrumentation within guests,
support of 248 VCPUs.
 
 * ARM: rewrite of the arm64 world switch in C, support for
 16-bit VM identifiers.  Performance counter virtualization
 missed the boat.
 
 * x86: Support for more Hyper-V features (synthetic interrupt
 controller), MMU cleanups
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "PPC changes will come next week.

   - s390: Support for runtime instrumentation within guests, support of
     248 VCPUs.

   - ARM: rewrite of the arm64 world switch in C, support for 16-bit VM
     identifiers.  Performance counter virtualization missed the boat.

   - x86: Support for more Hyper-V features (synthetic interrupt
     controller), MMU cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (115 commits)
  kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL
  kvm/x86: Hyper-V SynIC timers tracepoints
  kvm/x86: Hyper-V SynIC tracepoints
  kvm/x86: Update SynIC timers on guest entry only
  kvm/x86: Skip SynIC vector check for QEMU side
  kvm/x86: Hyper-V fix SynIC timer disabling condition
  kvm/x86: Reorg stimer_expiration() to better control timer restart
  kvm/x86: Hyper-V unify stimer_start() and stimer_restart()
  kvm/x86: Drop stimer_stop() function
  kvm/x86: Hyper-V timers fix incorrect logical operation
  KVM: move architecture-dependent requests to arch/
  KVM: renumber vcpu->request bits
  KVM: document which architecture uses each request bit
  KVM: Remove unused KVM_REQ_KICK to save a bit in vcpu->requests
  kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clock
  KVM: s390: implement the RI support of guest
  kvm/s390: drop unpaired smp_mb
  kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpa
  KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table()
  arm/arm64: KVM: Detect vGIC presence at runtime
  ...
2016-01-12 13:22:12 -08:00
Martin Schwidefsky
249c543b97 s390/vdso: optimize getcpu system call
Add the CPU number to the per-cpu vdso data page and add the
__kernel_getcpu function to the vdso object to retrieve the
CPU number in user space.

Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-11 13:01:24 +01:00
Michael S. Tsirkin
0dab3e0e59 s390: drop smp_mb in vdso_init
The initial s390 vdso code is heavily influenced by the powerpc version
which does have a smp_wmb in vdso_init right before the vdso_ready=1
assignment. s390 has no need for that.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <1452010645-25380-1-git-send-email-mst@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-11 12:27:22 +01:00
Heiko Carstens
c667aeacc1 s390: rename struct _lowcore to struct lowcore
Finally get rid of the leading underscore. I tried this already two or
three years ago, however Michael Holzheu objected since this would
break the crash utility (again).

However Michael integrated support for the new name into the crash
utility back then, so it doesn't break if the name will be changed
now.  So finally get rid of the ever confusing leading underscore.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-11 12:27:15 +01:00
Heiko Carstens
7022ec4960 s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields
Add missing multithreading fields of SYSIB 1.2.2 (Basic-Machine CPUs)
to the output of /proc/sysinfo.

Also use bitfields for SYSIB 2.2.2 to simplify the C code a bit.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-11 12:27:00 +01:00
Heiko Carstens
9236b4dd6b s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK
Use CONFIG_TOPOLOGY which selects CONFIG_SCHED_* all over the place to
reduce the random usage of the previous config options.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-30 10:34:57 +01:00
Heiko Carstens
3dbc78d3a1 s390/smp: save timestamp on external calls
This is supposed to make debugging easier: if within a dump we can see
that an external call or emergency signal IPI is pending but all cpus
are idle, we have no idea for how long the interrupt is outstanding.

Therefore save a timestamp into the per cpu pcpu array of the target
cpu whenever such an IPI is sent.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:31 +01:00
Christian Borntraeger
e527aec434 s390/sysinfo: Remove unused variables
max_mnest and rc are never used.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:30 +01:00
Christian Borntraeger
f9101e639c s390/traps: Remove unused variable
location is assigned but never used.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:27 +01:00
Heiko Carstens
6527f6e0cb s390: compile head.S always with -march=z900
head.S on s390 contains some sanity checks if the kernel will run on a
machine or if the machine is too old, e.g. if the kernel contains
instructions not available on the machine. If so, it will emit an error
message to the console before it stops execution.

Therefore head.S contains only instructions which are availanble with the
earliest machine generation (z900).  In order to make sure we don't
accidently add instructions which are not available on z900, always compile
with -march=z900. This makes sure compilation will fail if wrong
instructions are used.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:26 +01:00
Heiko Carstens
0358ecf732 s390/facilities: make use of generated facility list
Change head.S to make use of the generated facility list.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:21 +01:00
Heiko Carstens
76cdd44c2e s390/facilities: always use lowcore's stfle field for storing facility bits
head.s contains an stfle instruction which stores it result at the
storage location that is assigned to the stfl instruction.

This is currently no problem, since we only care about one double
word. However if the number of double words in the ALS bitfield grows
the current code is not very stable.

E.g. before issuing the stfle command the memory to which it stores
must be cleared, since the instruction may or may not clear memory
contents where no bits are set.

In order to simplify the code a bit always use the storage location
that we reserved for the stfle result.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:19 +01:00
Heiko Carstens
9552a66fe6 s390/facilities: use stfl mnemonic instead of insn magic
Now that 31 bit support is gone, the assembler always knows about the
stfl instruction. Therefore lets use a readable mnemonic.  Also remove
the not needed extable entry for the inline assembly and fix the
output constraint.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:59:18 +01:00
Michael Holzheu
272fa59ccb s390/dis: Fix handling of format specifiers
The print_insn() function returns strings like "lghi %r1,0". To escape the
'%' character in sprintf() a second '%' is used. For example "lghi %%r1,0"
is converted into "lghi %r1,0".

After print_insn() the output string is passed to printk(). Because format
specifiers like "%r" or "%f" are ignored by printk() this works by chance
most of the time. But for instructions with control registers like
"lctl %c6,%c6,780" this fails because printk() interprets "%c" as
character format specifier.

Fix this problem and escape the '%' characters twice.

For example "lctl %%%%c6,%%%%c6,780" is then converted by sprintf()
into "lctl %%c6,%%c6,780" and by printk() into "lctl %c6,%c6,780".

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18 14:43:21 +01:00
Rusty Russell
7523e4dc50 module: use a structure to encapsulate layout.
Makes it easier to handle init vs core cleanly, though the change is
fairly invasive across random architectures.

It simplifies the rbtree code immediately, however, while keeping the
core data together in the same cachline (now iff the rbtree code is
enabled).

Acked-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-12-04 22:46:25 +01:00
David Hildenbrand
7f16d7e787 s390: show virtualization support in /proc/cpuinfo
This patch exposes the SIE capability (aka virtualization support) via
/proc/cpuinfo -> "features" as "sie".

As we don't want to expose this hwcap via elf, let's add a second,
"internal"/non-elf capability list. The content is simply concatenated
to the existing features when printing /proc/cpuinfo.

We also add the defines to elf.h to keep the hwcap stuff at a common
place.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:11 +01:00
Martin Schwidefsky
419123f900 s390/spinlock: do not yield to a CPU in udelay/mdelay
It does not make sense to try to relinquish the time slice with diag 0x9c
to a CPU in a state that does not allow to schedule the CPU. The scenario
where this can happen is a CPU waiting in udelay/mdelay while holding a
spin-lock.

Add a CIF bit to tag a CPU in enabled wait and use it to detect that the
yield of a CPU will not be successful and skip the diagnose call.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:18 +01:00
Sascha Silbe
3f975df69d s390/sclp: Add VT220 support to early sclp console
When running under qemu with the default configuration (-nographic),
there is only a VT220 SCLP console, no line-mode SCLP console. Add
VT220 support to the early SCLP console so the user has a chance to
see critical error messages during early boot.

None of the existing users of _sclp_print_early() check the return
code. Instead of trying to come up with return code semantics when
printing to multiple consoles (any or all of which may fail), we just
drop the return code entirely.

Tested on z/VM (line mode console) and LPAR (VT220 and line mode
console). Tested on qemu/KVM with VT220 console and / or line mode
console.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:17 +01:00
Christian Borntraeger
561e103002 s390/dis: Fix printing of the register numbers
Since commit b006f19b05 ("lib/vsprintf.c: handle invalid format
specifiers more robustly") I get errors like
[...]
Krnl Code: 00000000004e2410: c00400000000        brcl 0,4e2410
Please remove unsupported %r in format string
[    8.179483] ------------[ cut here ]------------
[    8.179484] WARNING: at lib/vsprintf.c:1781

Turns out that our disassembler relied on %r not being used as format
string. Let's do the proper escaping of our decode buffers.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:16 +01:00
Martin Schwidefsky
1a2c5840ac s390/dump: cleanup CPU save area handling
Introduce save_area_alloc(), save_area_boot_cpu(), save_area_add_regs()
and save_area_add_vxrs to deal with storing the CPU state in case of a
system dump. Remove struct save_area and save_area_ext, and create a new
struct save_area as a local definition to arch/s390/kernel/crash_dump.c.
Copy each individual field from the hardware status area to the save area,
storing the minimum of required data.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:14 +01:00
Martin Schwidefsky
1a36a39e22 s390/dump: rework CPU register dump code
To collect the CPU registers of the crashed system allocated a single
page with memblock_alloc_base and use it as a copy buffer. Replace the
stop-and-store-status sigp with a store-status-at-address sigp in
smp_save_dump_cpus() and smp_store_status(). In both cases the target
CPU is already stopped and store-status-at-address avoids the detour
via the absolute zero page.

For kexec simplify s390_reset_system and call store_status() before
the prefix register of the boot CPU has been set to zero. Use STPX
to store the prefix register and remove dump_prefix_page.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:14 +01:00
Martin Schwidefsky
f08b841463 s390/dump: remove SAVE_AREA_BASE
Replace the SAVE_AREA_BASE offset calculations in reipl.S with the
assembler constant for the location of each register status area.

Use __LC_FPREGS_SAVE_AREA instead of SAVE_AREA_BASE in the three
remaining code locations and remove the definition of SAVE_AREA_BASE.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:14 +01:00
Martin Schwidefsky
d9a3a09af5 s390/kvm: remove dependency on struct save_area definition
Replace the offsets based on the struct area_area with the offset
constants from asm-offsets.c based on the struct _lowcore.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:13 +01:00
Martin Schwidefsky
df9694c797 s390/dump: streamline oldmem copy functions
Introduce two copy functions for the memory of the dumped system,
copy_oldmem_kernel() to copy to the virtual kernel address space
and copy_oldmem_user() to copy to user space.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:12 +01:00
Martin Schwidefsky
8a07dd02d7 s390/kdump: remove code to create ELF notes in the crashed system
The s390 architecture can store the CPU registers of the crashed system
after the kdump kernel has been started and this is the preferred way.
Remove the remaining code fragments that deal with storing CPU registers
while the crashed system is still active.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:12 +01:00
Heiko Carstens
f52c74fee9 s390: remove SALIPL loader
There is no known user, therefore remove the code.

Acked-by: Rob Van Der Heij <robvdheij@nl.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16 12:51:11 +01:00
Heiko Carstens
932f608193 s390: wire up mlock2 system call
Passes mlock2-tests test case in 64 bit and compat mode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16 12:51:07 +01:00
Heiko Carstens
ddfd4a054b s390: remove g5 elf platform support
Remove dead code, since this could only happen on a 31 bit machine
where the kernel wouldn't IPL.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16 12:04:41 +01:00
Martin Schwidefsky
c7e8b2c21c s390: avoid cache aliasing under z/VM and KVM
commit 1f6b83e5e4 ("s390: avoid z13 cache aliasing") checks for the
machine type to optimize address space randomization and zero page
allocation to avoid cache aliases.

This check might fail under a hypervisor with migration support.
z/VMs "Single System Image and Live Guest Relocation" facility will
"fake" the machine type of the oldest system in the group. For example
in a group of zEC12 and Z13 the guest appears to run on a zEC12
(architecture fencing within the relocation domain)

Remove the machine type detection and always use cache aliasing
rules that are known to work for all machines. These are the z13
aliasing rules.

Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16 12:04:18 +01:00
Sascha Silbe
f07f21b3e2 s390/sclp: _sclp_wait_int(): retain full PSW mask
There's no reason to clear all PSW mask bits other than the addressing
mode bits. Just use the previous PSW mask as-is.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-12 13:08:00 +01:00
Sebastian Ott
18e22a1772 s390: add support for ipl devices in subchannel sets > 0
Allow to ipl from CCW based devices residing in any subchannel set.

Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11 13:56:27 +01:00
Sebastian Ott
e0bedada3a s390/ipl: fix out of bounds access in scpdata_write
The input buffer in reipl_fcp_scpdata_write is accessed out of bounds
when an offset is specified. The problem is that the offset refers to
the data we should write to and not to the buffer we read from.

So instead of
        memcpy(scp_data, buf + off, count);
we could just do
        memcpy(scp_data + off, buf, count);

However we not only modify the data but also store its length. For this to
work we'd need to remember a state per open FH. Since that's not possible
with sysfs callbacks let's just fail when an offset is specified.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11 09:07:06 +01:00
Martin Schwidefsky
230ccb370f s390/diag: add a s390 prefix to the diagnose trace point
Documentation/trace/tracepoints.txt states that the naming scheme
for tracepoints is "subsys_event" to avoid collisions. Rename
the 'diagnose' tracepoint to 's390_diagnose'.

Reported-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:47 +01:00
Sascha Silbe
c6eafbf990 s390/head: fix error message on unsupported hardware
startup calls the C function _sclp_print_early() if the machine we're
running on is not supported by the kernel. sclp.c is getting built
with -m64, so _sclp_print_early() expects the zSeries ELF ABI to be
used.

We previously called _sclp_print_early() using the S/390 ELF ABI, with
a stack frame size of 96 bytes and while being in 31-bit address
mode. This caused _sclp_wait_int() (called indirectly from
_sclp_print_early()) to jump to an undefined address. While
_sclp_wait_int() contained some code to deal with being called in
31-bit addressing mode, it didn't quite work. While fixing this is
possible, the code would still only work by chance and could break any
time.

Ensure compliance with the zSeries ELF ABI by switching to 64-bit
addressing mode early and using a minimum stack frame size of 160
bytes.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:47 +01:00
Linus Torvalds
e627078a0c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "There is only one new feature in this pull for the 4.4 merge window,
  most of it is small enhancements, cleanup and bug fixes:

   - Add the s390 backend for the software dirty bit tracking.  This
     adds two new pgtable functions pte_clear_soft_dirty and
     pmd_clear_soft_dirty which is why there is a hit to
     arch/x86/include/asm/pgtable.h in this pull request.

   - A series of cleanup patches for the AP bus, this includes the
     removal of the support for two outdated crypto cards (PCICC and
     PCICA).

   - The irq handling / signaling on buffer full in the runtime
     instrumentation code is dropped.

   - Some micro optimizations: remove unnecessary memory barriers for a
     couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for
     spin_unlock.  Use the builtin bswap if available and make
     test_and_set_bit_lock more cache friendly.

   - Statistics and a tracepoint for the diagnose calls to the
     hypervisor.

   - The CPU measurement facility support to sample KVM guests is
     improved.

   - The vector instructions are now always enabled for user space
     processes if the hardware has the vector facility.  This simplifies
     the FPU handling code.  The fpu-internal.h header is split into fpu
     internals, api and types just like x86.

   - Cleanup and improvements for the common I/O layer.

   - Rework udelay to solve a problem with kprobe.  udelay has busy loop
     semantics but still uses an idle processor state for the wait"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
  s390: remove runtime instrumentation interrupts
  s390/cio: de-duplicate subchannel validation
  s390/css: unneeded initialization in for_each_subchannel
  s390/Kconfig: use builtin bswap
  s390/dasd: fix disconnected device with valid path mask
  s390/dasd: fix invalid PAV assignment after suspend/resume
  s390/dasd: fix double free in dasd_eckd_read_conf
  s390/kernel: fix ptrace peek/poke for floating point registers
  s390/cio: move ccw_device_stlck functions
  s390/cio: move ccw_device_call_handler
  s390/topology: reduce per_cpu() invocations
  s390/nmi: reduce size of percpu variable
  s390/nmi: fix terminology
  s390/nmi: remove casts
  s390/nmi: remove pointless error strings
  s390: don't store registers on disabled wait anymore
  s390: get rid of __set_psw_mask()
  s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
  s390/dasd: fix list_del corruption after lcu changes
  s390/spinlock: remove unneeded serializations at unlock
  ...
2015-11-04 11:31:31 -08:00
Martin Schwidefsky
b38feccd66 s390: remove runtime instrumentation interrupts
The external interrupts for runtime instrumentation buffer-full
and runtime instrumentation halted are unused and have no current
user. Remove the support and ignore the second parameter of the
s390_runtime_instr system call from now on.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03 14:40:51 +01:00
Martin Schwidefsky
55a423b6f1 s390/kernel: fix ptrace peek/poke for floating point registers
git commit 155e839a81
"s390/kernel: dynamically allocate FP register save area"
introduced a regression in regard to ptrace.

If the vector register extension is not present or unused the
ptrace peek of a floating pointer register return incorrect data
and the ptrace poke to a floating pointer register overwrites the
task structure starting at task->thread.fpu.fprs.

Cc: stable@kernel.org # v4.3
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03 14:40:42 +01:00
Heiko Carstens
439eb131f7 s390/topology: reduce per_cpu() invocations
Each per_cpu() invocation generates extra code. Since there are a lot
of similiar calls in the topology code we can avoid a lot of them.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:34:39 +01:00
Heiko Carstens
36324963a3 s390/nmi: reduce size of percpu variable
Change the flag fields within struct mcck_struct to simple bit fields
to reduce the size of the structure which is used as percpu variable.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:57 +01:00
Heiko Carstens
975be635d9 s390/nmi: fix terminology
According to the architecture registers are validated and not
revalidated. So change comments and functions names to match.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:56 +01:00
Heiko Carstens
dc6e15556a s390/nmi: remove casts
Remove all the casts to and from the machine check interruption code.
This patch changes struct mci to a union, which contains an anonymous
structure with the already known bits and in addition an unsigned
long field, which contains the raw machine check interruption code.

This allows to simply assign and decoce the interruption code value
without the need for all those casts we had all the time.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:55 +01:00
Heiko Carstens
3d68286a43 s390/nmi: remove pointless error strings
s390_handle_damage() has character string parameter which was used as
a pointer to verbose error message. The hope was (a lot of years ago)
when analyzing dumps that register R2 would still contain the pointer
and therefore it would be rather easy to tell what went wrong.

However gcc optimizes the strings away since a long time. And even if
it wouldn't it is necessary to have a close look at the machine check
interruption code to tell what's wrong.

So remove the pointless error strings.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:54 +01:00
Hendrik Brueckner
b0753902d4 s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
Split the API and FPU type definitions into separate header files
similar to "x86/fpu: Rename fpu-internal.h to fpu/internal.h" (78f7f1e54b).

The new header files and their meaning are:

asm/fpu/types.h:
	FPU related data types, needed for 'struct thread_struct' and
	'struct task_struct'.

asm/fpu/api.h:
	FPU related 'public' functions for other subsystems and device
	drivers.

asm/fpu/internal.h:
	FPU internal functions mainly used to convert
	FPU register contents in signal handling.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-16 09:41:12 +02:00
Heiko Carstens
29b0a8250b s390/etr,stp: fix possible deadlock on machine check
The first level machine check handler for etr and stp machine checks may
call queue_work() while in nmi context. This may deadlock e.g. if the
machine check happened when the interrupted context did hold a lock, that
also will be acquired by queue_work().
Therefore split etr and stp machine check handling into first and second
level handling. The second level handling will then issue the queue_work()
call in process context which avoids the potential deadlock.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:18 +02:00
Heiko Carstens
db7e007fd6 s390/udelay: make udelay have busy loop semantics
When using systemtap it was observed that our udelay implementation is
rather suboptimal if being called from a kprobe handler installed by
systemtap.

The problem observed when a kprobe was installed on lock_acquired().
When the probe was hit the kprobe handler did call udelay, which set
up an (internal) timer and reenabled interrupts (only the clock comparator
interrupt) and waited for the interrupt.
This is an optimization to avoid that the cpu is busy looping while waiting
that enough time passes. The problem is that the interrupt handler still
does call irq_enter()/irq_exit() which then again can lead to a deadlock,
since some accounting functions may take locks as well.

If one of these locks is the same, which caused lock_acquired() to be
called, we have a nice deadlock.

This patch reworks the udelay code for the interrupts disabled case to
immediately leave the low level interrupt handler when the clock
comparator interrupt happens. That way no C code is being called and the
deadlock cannot happen anymore.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:13 +02:00
Christian Borntraeger
e22cf8ca6f s390/cpumf: rework program parameter setting to detect guest samples
The program parameter can be used to mark hardware samples with
some token.  Previously, it was used to mark guest samples only.

Improve the program parameter doubleword by combining two parts,
the leftmost LPP part and the rightmost PID part.  Set the PID
part for processes by using the task PID.
To distinguish host and guest samples for the kernel (PID part
is zero), the guest must always set the program paramater to a
non-zero value.  Use the leftmost bit in the LPP part of the
program parameter to be able to detect guest kernel samples.

[brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced
__LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts.
And updated the commit message accordingly.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:12 +02:00
Martin Schwidefsky
6a62b485ea s390/asm: make use of the OFFSET macro to define assember constants
The use of OFFSET instead of DEFINE makes the definitions in asm-offsets.c
more readable. While we are at it sort the defines for struct _lowcore
according to the field order and remove some unneeded defines.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:10 +02:00
Hendrik Brueckner
83abeffbd5 s390/entry: add assembler macro to conveniently tests under mask
Various functions in entry.S perform test-under-mask instructions
to test for particular bits in memory.  Because test-under-mask uses
a mask value of one byte, the mask value and the offset into the
memory must be calculated manually.  This easily introduces errors
and is hard to review and read.

Introduce the TSTMSK assembler macro to specify a mask constant and
let the macro calculate the offset and the byte mask to generate a
test-under-mask instruction.  The benefit is that existing symbolic
constants can now be used for tests.  Also the macro checks for
zero mask values and mask values that consist of multiple bytes.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:09 +02:00
Hendrik Brueckner
0ac277790e s390/fpu: add static FPU save area for init_task
Previously, the init task did not have an allocated FPU save area and
saving an FPU state was not possible.  Now if the vector extension is
always enabled, provide a static FPU save area to save FPU states of
vector instructions that can be executed quite early.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:08 +02:00
Hendrik Brueckner
b5510d9b68 s390/fpu: always enable the vector facility if it is available
If the kernel detects that the s390 hardware supports the vector
facility, it is enabled by default at an early stage.  To force
it off, use the novx kernel parameter.  Note that there is a small
time window, where the vector facility is enabled before it is
forced to be off.

With enabling the vector facility by default, the FPU save and
restore functions can be improved.  They do not longer require
to manage expensive control register updates to enable or disable
the vector enablement control for particular processes.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:08 +02:00
Martin Schwidefsky
b5a6b71b19 s390/diag: add tracepoint for diagnose calls
To be able to analyse problems in regard to hypervisor overhead
add a tracepoing for diagnose calls. It reports the number of
the diagnose issued, e.g.

            sshd-1385  [002] ....    42.701431: diagnose: nr=0x9c
          <idle>-0     [001] ..s.    43.587528: diagnose: nr=0x9c

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:06 +02:00
Martin Schwidefsky
1ec2772e0c s390/diag: add a statistic for diagnose calls
Introduce /sys/debug/kernel/diag_stat with a statistic how many diagnose
calls have been done by each CPU in the system.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:06 +02:00
Alexander Kuleshov
3c4aac86cb s390/crash_dump: use for_each_mem_range
The <linux/memblock.h> already provides for_each_mem_range() macro that
iterates through memblock areas from type_a and not included in type_b.
We can remove custom for_each_dump_mem_range() macro and use the
for_each_mem_range() instead.

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2015-10-14 14:32:01 +02:00
Christian Borntraeger
33b5881d11 s390/vdso: use correct memory barrier
By definition smp_wmb only orders writes against writes. (Finish all
previous writes, and do not start any future write). To protect the
vdso init code against early reads on other CPUs, let's use a full
smp_mb at the end of vdso init. As right now smp_wmb is implemented
as full serialization, this needs no stable backport, but this change
will be necessary if we reimplement smp_wmb.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:01 +02:00
Ingo Molnar
d3df65c198 Merge branch 'perf/urgent' into perf/core, before pulling new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-08 10:52:18 +02:00
Martin Schwidefsky
72d38b1978 s390/vtime: correct scaled cputime of partially idle CPUs
The calculation for the SMT scaling factor for a hardware thread
which has been partially idle needs to disregard the cycles spent
by the other threads of the core while the thread is idle.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-30 16:22:38 +02:00
Ingo Molnar
6afc0c269c Merge branch 'linus' into perf/core, to pick up fixes before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-28 08:06:57 +02:00
Heiko Carstens
977108f89c s390: wire up separate socketcalls system calls
As discussed on linux-arch all architectures should wire up the separate
system calls that are hidden behind the socketcall multiplexer system call.

It's just a couple more system calls and gives us a very small performance
improvement.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-18 11:16:53 +02:00
Heiko Carstens
7681df456f s390/compat: remove superfluous compat wrappers
A couple of compat wrapper functions are simply trampolines to the real
system call. This happened because the compat wrapper defines will only
sign and zero extend system call parameters which are of different size
on s390/s390x (longs and pointers).
All other parameters will be correctly sign and zero extended by the
normal system call wrappers.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-18 11:16:52 +02:00
Heiko Carstens
a55b2ae78c s390/compat: do not trace compat wrapper functions
Add notrace to the compat wrapper define to disable tracing of compat
wrapper functions. These are supposed to be very small and more or less
just a trampoline to the real system call.

Also fix indentation.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-18 11:16:50 +02:00
Mathieu Desnoyers
96d4ee8aaa s390/s390x: allocate sys_membarrier system call number
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: linux-api@vger.kernel.org
CC: Heiko Carstens <heiko.carstens@de.ibm.com>
CC: linux-s390@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:44 +02:00
Heiko Carstens
022435713c s390: wire up userfaultfd system call
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:43 +02:00
Martin Schwidefsky
61cc37906b s390/vtime: correct scaled cputime for SMT
The scaled cputime is supposed to be derived from the normal per-thread
cputime by dividing it with the average thread density in the last interval.

The calculation of the scaling values for the average thread density is
incorrect. The current, incorrect calculation:

    Ci = cycle count with i active threads
    T = unscaled cputime, sT = scaled cputime
    sT = T * (C1 + C2 + ... + Cn) / (1*C1 + 2*C2 + ... + n*Cn)

The calculation happens to yield the correct numbers for the simple cases
with only one Ci value not zero. But for cases with multiple Ci values not
zero it fails. E.g. on a SMT-2 system with one thread active half the time
and two threads active for the other half of the time it fails, the scaling
factor should be 3/4 but the formula gives 2/3.

The correct formula is

    sT = T * (C1/1 + C2/2 + ... + Cn/n) / (C1 + C2 + ... + Cn)

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:43 +02:00
Hendrik Brueckner
58f8e9da33 s390/cpum_cf: Corrected return code for unauthorized counter sets
Previously, the cpum_cf PMU returned -EPERM if a counter is requested and
the counter set to which the counter belongs is not authorized.  According
to the perf_event_open() system call manual, an error code of EPERM indicates
an unsupported exclude setting or CAP_SYS_ADMIN is missing.

Use ENOENT to indicate that particular counters are not available when the
counter set which contains the counter is not authorized.  For generic events,
this might trigger a fall back, for example, to a software event.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:42 +02:00
Martin Schwidefsky
8d4bd0ed04 s390/compat: correct uc_sigmask of the compat signal frame
The uc_sigmask in the ucontext structure is an array of words to keep
the 64 signal bits (or 1024 if you ask glibc but the kernel sigset_t
only has 64 bits).

For 64 bit the sigset_t contains a single 8 byte word, but for 31 bit
there are two 4 byte words. The compat signal handler code uses a
simple copy of the 64 bit sigset_t to the 31 bit compat_sigset_t.
As s390 is a big-endian architecture this is incorrect, the two words
in the 31 bit sigset_t array need to be swapped.

Cc: <stable@vger.kernel.org>
Reported-by: Stefan Liebler <stli@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:42 +02:00
Heiko Carstens
9380cf5a88 s390: fix floating point register corruption
The critical section cleanup code misses to add the offset of the
thread_struct to the task address.
Therefore, if the critical section code gets executed, it may corrupt
the task struct or restore the contents of the floating point registers
from the wrong memory location.
Fixes d0164ee20d "s390/kernel: remove save_fpu_regs() parameter and use
__LC_CURRENT instead".

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:41 +02:00
Martin Schwidefsky
88d6425378 s390/hibernate: fix save and restore of vector registers
The swsusp_arch_suspend()/swsusp_arch_resume() functions currently only
save and restore the floating point registers. If the task that started
the hibernation process is using vector registers they can get lost.
To fix this just call save_fpu_regs in swsusp_arch_suspend(), the restore
will happen automatically on return to user space.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:41 +02:00
Sukadev Bhattiprolu
8f3e5684d3 perf/core: Drop PERF_EVENT_TXN
We currently use PERF_EVENT_TXN flag to determine if we are in the middle
of a transaction. If in a transaction, we defer the schedulability checks
from pmu->add() operation to the pmu->commit() operation.

Now that we have "transaction types" (PERF_PMU_TXN_ADD, PERF_PMU_TXN_READ)
we can use the type to determine if we are in a transaction and drop the
PERF_EVENT_TXN flag.

When PERF_EVENT_TXN is dropped, the cpuhw->group_flag on some architectures
becomes unused, so drop that field as well.

This is an extension of the Powerpc patch from Peter Zijlstra to s390,
Sparc and x86 architectures.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-11-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-13 11:27:30 +02:00
Sukadev Bhattiprolu
fbbe070115 perf/core: Add a 'flags' parameter to the PMU transactional interfaces
Currently, the PMU interface allows reading only one counter at a time.
But some PMUs like the 24x7 counters in Power, support reading several
counters at once. To leveage this functionality, extend the transaction
interface to support a "transaction type".

The first type, PERF_PMU_TXN_ADD, refers to the existing transactions,
i.e. used to _schedule_ all the events on the PMU as a group. A second
transaction type, PERF_PMU_TXN_READ, will be used in a follow-on patch,
by the 24x7 counters to read several counters at once.

Extend the transaction interfaces to the PMU to accept a 'txn_flags'
parameter and use this parameter to ignore any transactions that are
not of type PERF_PMU_TXN_ADD.

Thanks to Peter Zijlstra for his input.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
[peterz: s390 compile fix]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-3-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-13 11:27:25 +02:00
Linus Torvalds
ca520cab25 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and atomic updates from Ingo Molnar:
 "Main changes in this cycle are:

   - Extend atomic primitives with coherent logic op primitives
     (atomic_{or,and,xor}()) and deprecate the old partial APIs
     (atomic_{set,clear}_mask())

     The old ops were incoherent with incompatible signatures across
     architectures and with incomplete support.  Now every architecture
     supports the primitives consistently (by Peter Zijlstra)

   - Generic support for 'relaxed atomics':

       - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
       - atomic_read_acquire()
       - atomic_set_release()

     This came out of porting qwrlock code to arm64 (by Will Deacon)

   - Clean up the fragile static_key APIs that were causing repeat bugs,
     by introducing a new one:

       DEFINE_STATIC_KEY_TRUE(name);
       DEFINE_STATIC_KEY_FALSE(name);

     which define a key of different types with an initial true/false
     value.

     Then allow:

       static_branch_likely()
       static_branch_unlikely()

     to take a key of either type and emit the right instruction for the
     case.  To be able to know the 'type' of the static key we encode it
     in the jump entry (by Peter Zijlstra)

   - Static key self-tests (by Jason Baron)

   - qrwlock optimizations (by Waiman Long)

   - small futex enhancements (by Davidlohr Bueso)

   - ... and misc other changes"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
  jump_label/x86: Work around asm build bug on older/backported GCCs
  locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
  locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
  locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
  locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
  locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
  locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
  locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
  locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
  locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
  locking/static_keys: Make verify_keys() static
  jump label, locking/static_keys: Update docs
  locking/static_keys: Provide a selftest
  jump_label: Provide a self-test
  s390/uaccess, locking/static_keys: employ static_branch_likely()
  x86, tsc, locking/static_keys: Employ static_branch_likely()
  locking/static_keys: Add selftest
  locking/static_keys: Add a new static_key interface
  locking/static_keys: Rework update logic
  locking/static_keys: Add static_key_{en,dis}able() helpers
  ...
2015-09-03 15:46:07 -07:00
Linus Torvalds
5e359bf221 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Rather large, but nothing exiting:

   - new range check for settimeofday() to prevent that boot time
     becomes negative.
   - fix for file time rounding
   - a few simplifications of the hrtimer code
   - fix for the proc/timerlist code so the output of clock realtime
     timers is accurate
   - more y2038 work
   - tree wide conversion of clockevent drivers to the new callbacks"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (88 commits)
  hrtimer: Handle failure of tick_init_highres() gracefully
  hrtimer: Unconfuse switch_hrtimer_base() a bit
  hrtimer: Simplify get_target_base() by returning current base
  hrtimer: Drop return code of hrtimer_switch_to_hres()
  time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64()
  time: Introduce current_kernel_time64()
  time: Introduce struct itimerspec64
  time: Add the common weak version of update_persistent_clock()
  time: Always make sure wall_to_monotonic isn't positive
  time: Fix nanosecond file time rounding in timespec_trunc()
  timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers
  cris/time: Migrate to new 'set-state' interface
  kernel: broadcast-hrtimer: Migrate to new 'set-state' interface
  xtensa/time: Migrate to new 'set-state' interface
  unicore/time: Migrate to new 'set-state' interface
  um/time: Migrate to new 'set-state' interface
  sparc/time: Migrate to new 'set-state' interface
  sh/localtimer: Migrate to new 'set-state' interface
  score/time: Migrate to new 'set-state' interface
  s390/time: Migrate to new 'set-state' interface
  ...
2015-09-01 14:04:50 -07:00
Linus Torvalds
9c6a019c6e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "The big one is support for fake NUMA, splitting a really large machine
  in more manageable piece improves performance in some cases, e.g. for
  a KVM host.

  The FICON Link Incident handling has been improved, this helps the
  operator to identify degraded or non-operational FICON connections.

  The save and restore of floating point and vector registers has been
  overhauled to allow the future use of vector registers in the kernel.

  A few small enhancement, magic sys-requests for the vt220 console via
  SCLP, some more assembler code has been converted to C, the PCI error
  handling is improved.

  And the usual cleanup and bug fixing"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits)
  s390/jump_label: Use %*ph to print small buffers
  s390/sclp_vt220: support magic sysrequests
  s390/ctrlchar: improve handling of magic sysrequests
  s390/numa: remove superfluous ARCH_WANT defines
  s390/3270: redraw screen on unsolicited device end
  s390/dcssblk: correct out of bounds array indexes
  s390/mm: simplify page table alloc/free code
  s390/pci: move debug messages to debugfs
  s390/nmi: initialize control register 0 earlier
  s390/zcrypt: use msleep() instead of mdelay()
  s390/hmcdrv: fix interrupt registration
  s390/setup: fix novx parameter
  s390/uaccess: remove uaccess_primary kernel parameter
  s390: remove unneeded sizeof(void *) comparisons
  s390/facilities: remove transactional-execution bits
  s390/numa: re-add DIE sched_domain_topology_level
  s390/dasd: enhance CUIR scope detection
  s390/dasd: fix failing path verification
  s390/vdso: emit a GNU hash
  s390/numa: make core to node mapping data dynamic
  ...
2015-08-31 15:11:53 -07:00
Linus Torvalds
44e98edcd1 A very small release for x86 and s390 KVM.
s390: timekeeping changes, cleanups and fixes
 
 x86: support for Hyper-V MSRs to report crashes, and a bunch of cleanups.
 
 One interesting feature that was planned for 4.3 (emulating the local
 APIC in kernel while keeping the IOAPIC and 8254 in userspace) had to
 be delayed because Intel complained about my reading of the manual.
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Merge tag 'kvm-4.3-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "A very small release for x86 and s390 KVM.

   - s390: timekeeping changes, cleanups and fixes

   - x86: support for Hyper-V MSRs to report crashes, and a bunch of
     cleanups.

  One interesting feature that was planned for 4.3 (emulating the local
  APIC in kernel while keeping the IOAPIC and 8254 in userspace) had to
  be delayed because Intel complained about my reading of the manual"

* tag 'kvm-4.3-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
  x86/kvm: Rename VMX's segment access rights defines
  KVM: x86/vPMU: Fix unnecessary signed extension for AMD PERFCTRn
  kvm: x86: Fix error handling in the function kvm_lapic_sync_from_vapic
  KVM: s390: Fix assumption that kvm_set_irq_routing is always run successfully
  KVM: VMX: drop ept misconfig check
  KVM: MMU: fully check zero bits for sptes
  KVM: MMU: introduce is_shadow_zero_bits_set()
  KVM: MMU: introduce the framework to check zero bits on sptes
  KVM: MMU: split reset_rsvds_bits_mask_ept
  KVM: MMU: split reset_rsvds_bits_mask
  KVM: MMU: introduce rsvd_bits_validate
  KVM: MMU: move FNAME(is_rsvd_bits_set) to mmu.c
  KVM: MMU: fix validation of mmio page fault
  KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ON
  KVM: s390: host STP toleration for VMs
  KVM: x86: clean/fix memory barriers in irqchip_in_kernel
  KVM: document memory barriers for kvm->vcpus/kvm->online_vcpus
  KVM: x86: remove unnecessary memory barriers for shared MSRs
  KVM: move code related to KVM_SET_BOOT_CPU_ID to x86
  KVM: s390: log capability enablement and vm attribute changes
  ...
2015-08-31 08:27:44 -07:00
Alexander Kuleshov
e4ec735108 s390/jump_label: Use %*ph to print small buffers
printk() supports %*ph format specifier for printing a small buffers,
let's use it intead of %02x %02x...

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-27 09:39:04 +02:00
Heiko Carstens
24d05ff863 s390/nmi: initialize control register 0 earlier
Change machine_check_init() to an early_initcall(). This makes sure it will
be called before all other cpus are online and therfore saves us a lot of
pointless smp_call_function() calls.
The control register settings will be forwarded to the other cpus when they
will be brought online.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-19 10:40:38 +02:00
Martin Schwidefsky
89b1145e93 s390/setup: fix novx parameter
The novx parameter disables the vector facility but the HWCAP_S390_VXRS
bit in the ELf hardware capabilies is always set if the machine has
the vector facility. If the user space program uses the "vx" string
in the features field of /proc/cpuinfo to utilize vector instruction
it will crash if the novx kernel paramter is set.

Convert setup_hwcaps to an arch_initcall and use MACHINE_HAS_VX to
decide if the HWCAPS_S390_VXRS bit needs to be set.

Cc: stable@vger.kernel.org # 3.18+
Reported-by: Ulrich Weigand <uweigand@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-19 10:40:04 +02:00
Heiko Carstens
a69db2f6ad s390/facilities: remove transactional-execution bits
Remove the two facility bits

50 - constrained transactional-execution facility
74 - transactional-execution facility

from the required facilities if the kernel is built with -march=zEC12.

E.g. z/VM 6.3 doesn't virtualize the TX facility yet. Therefore a kernel
built with -march=zEC12 and ipl'ed on a zEC12 machine as a z/VM 6.3 guest
will emit a message about the missing facilities and stop working.

The kernel however doesn't make use of the TX facility, therefore remove
the two TX related facility bits and fix this unpleasant behavior.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-19 10:03:34 +02:00
Michael Holzheu
c0e5ddab6e s390/numa: re-add DIE sched_domain_topology_level
By accident this level has been removed by the NUMA infrastructure patch.
For non-NUMA systems with CPUs that span more than one book, this makes
the scheduler only use one of the books and the other books remain idle.

Fix this and re-add the missing level.

For NUMA and non-NUMA we have the following scheduling domains and groups:

 - SMT  (Groups: CPU threads)
 - MC   (Groups: Cores)
 - BOOK (Groups: Books)

For the non-NUMA case we have one last level scheduling domain:

 - DIE  (Groups: Whole system, has all CPUs -> cpu_cpu_mask)

For the NUMA case we have the following two last level scheduling domains:

 - DIE  (Groups: NUMA nodes -> cpu_cpu_mask -> returns node siblings)
 - NUMA (Groups: Whole system, has all CPUs -> created in sched_init_numa())

Fixes: e8054b654b ("s390/numa: add topology tree infrastructure")
Reported-and-tested-by: Evgeny Cherkashin <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-19 10:03:14 +02:00
Ingo Molnar
f52609fdab Merge branch 'locking/arch-atomic' into locking/core, because it's ready for upstream
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 11:44:30 +02:00
Viresh Kumar
07aeed3f9b s390/time: Migrate to new 'set-state' interface
Migrate s390 driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

We weren't doing anything in the ->set_mode() callback. So, this patch
doesn't provide any set-state callbacks.

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: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-08-10 11:41:03 +02:00
Martin Schwidefsky
aad1b688c9 s390/vdso: emit a GNU hash
As proposed by Andy Lutomirski create the SysV and the GNU hash
for the vdso objects. This may make some dynamic loaders a bit
faster.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-07 09:57:39 +02:00
Michael Holzheu
3a3814c28b s390/topology: remove topology lock
Since we are already protected by the "sched_domains_mutex" lock, we can
safely remove the topology lock.

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>
2015-08-07 09:56:58 +02:00
Fan Zhang
fdf036507f KVM: s390: host STP toleration for VMs
If the host has STP enabled, the TOD of the host will be changed during
synchronization phases. These are performed during a stop_machine() call.

As the guest TOD is based on the host TOD, we have to make sure that:
- no VCPU is in the SIE (implicitly guaranteed via stop_machine())
- manual guest TOD calculations are not affected

"Epoch" is the guest TOD clock delta to the host TOD clock. We have to
adjust that value during the STP synchronization and make sure that code
that accesses the epoch won't get interrupted in between (via disabling
preemption).

Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-08-04 14:38:37 +02:00