Commit Graph

1521 Commits

Author SHA1 Message Date
Paolo Bonzini 1c2af4968e Merge tag 'kvm-for-3.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into kvm-next 2014-03-04 15:58:00 +01:00
Cornelia Huck 96b14536d9 virtio-ccw: virtio-ccw adapter interrupt support.
Implement the new CCW_CMD_SET_IND_ADAPTER command and try to enable
adapter interrupts for every device on the first startup. If the host
does not support adapter interrupts, fall back to normal I/O interrupts.

virtio-ccw adapter interrupts use the same isc as normal I/O subchannels
and share a summary indicator for all devices sharing the same indicator
area.

Indicator bits for the individual virtqueues may be contained in the same
indicator area for different devices.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-03-04 10:41:04 +01:00
Heiko Carstens c2e7c3d0ef s390/compat: partial parameter conversion within syscall wrappers
Parameter conversion within the system call wrappers is only needed
for parameters which differ in size and have a size of eight bytes on
64 bit.
For system call parameters with a size of less than eight byte the
called system call itself will perform parameter conversion anyway.
So we can save the double conversion of e.g. int parameters.

The only types which need to be converted are therefore pointer and
(unsigned) long parameters.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:12:25 +01:00
Heiko Carstens ab4f8bba19 s390/compat: automatic zero, sign and pointer conversion of syscalls
Instead of explicitly changing compat system call parameters from e.g.
unsigned long to compat_ulong_t let the COMPAT_SYSCALL_WRAP macros
automatically detect (unsigned) long parameters and zero and sign
extend them automatically.
The resulting binary is completely identical.

In addition add a sys_[system call name] prototype for each system call
wrapper. This will cause compile errors if the prototype does not match
the prototype in include/linux/syscall.h.
Therefore we should now always get the correct zero and sign extension
of system call parameters. Pointers are handled like before.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:12:24 +01:00
Heiko Carstens 2c81fc4fb4 s390/compat: add sync_file_range and fallocate compat syscalls
The compat syscall wrappers for sync_file_range and fallocate merged 32 bit
parameters into 64 bit parameters. Therefore they did more than just the
usual zero and/or sign extension of system call parameters.

So convert these two wrappers to full s390 specific compat sytem calls.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:47 +01:00
Heiko Carstens 00fcb1494f s390/compat: convert system call wrappers to C part 15
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:46 +01:00
Heiko Carstens 7f6afe87a0 s390/compat: convert system call wrappers to C part 14
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:46 +01:00
Heiko Carstens 28798abc9c s390/compat: convert system call wrappers to C part 13
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:45 +01:00
Heiko Carstens 20f7835c0e s390/compat: convert system call wrappers to C part 12
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:45 +01:00
Heiko Carstens 9c4d62fab4 s390/compat: convert system call wrappers to C part 11
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:44 +01:00
Heiko Carstens 18421166e8 s390/compat: convert system call wrappers to C part 10
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:43 +01:00
Heiko Carstens 24e4c2aaef s390/compat: convert system call wrappers to C part 09
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:43 +01:00
Heiko Carstens 47b3ae9b8c s390/compat: convert system call wrappers to C part 08
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:42 +01:00
Heiko Carstens 0ebe3eec1e s390/compat: convert system call wrappers to C part 07
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:42 +01:00
Heiko Carstens ce5cef7ede s390/compat: convert system call wrappers to C part 06
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:41 +01:00
Heiko Carstens 86d295e1cc s390/compat: convert system call wrappers to C part 05
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:40 +01:00
Heiko Carstens c355ce182a s390/compat: convert system call wrappers to C part 04
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:40 +01:00
Heiko Carstens be06fbf816 s390/compat: convert system call wrappers to C part 03
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:39 +01:00
Heiko Carstens 473a06572f s390/compat: convert system call wrappers to C part 02
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:39 +01:00
Heiko Carstens b07edab23c s390/compat: convert system call wrappers to C part 01
Introduce a new compat_wrap.c file which contains the s390 specific compat
system call wrappers.
The s390 specific system call wrappers only perform sign, zero and pointer
conversion of system call arguments before actually calling the non-compat
system call.

Therefore introduce COMPAT_SYSCALL_WRAPx macros which generate C code that
is nearly identical to the assembly code. This has the advantage that the
compile will generate correct code, and we avoid the frequent copy-paste
errors seen in the compat_wrapper.S file.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:38 +01:00
Heiko Carstens 5383d2c8b3 s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 7
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:38 +01:00
Heiko Carstens a0f8c6da8f s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 6
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:37 +01:00
Heiko Carstens 52a0b536a3 s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 5
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:36 +01:00
Heiko Carstens e723e0cc17 s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 4
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:36 +01:00
Heiko Carstens 4ca2ea58c8 s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 3
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:35 +01:00
Heiko Carstens 208096eee2 s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 2
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:35 +01:00
Heiko Carstens c6c0f58f90 s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 1
Convert s390 specific system calls to to the new COMPAT_SYSCALL_DEFINE macro.
This allows us to get rid of the assembly compat wrappers.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-04 09:05:34 +01:00
Martin Schwidefsky 53e857f308 s390/mm,tlb: race of lazy TLB flush vs. recreation of TLB entries
Git commit 050eef364a "[S390] fix tlb flushing vs. concurrent
/proc accesses" introduced the attach counter to avoid using the
mm_users value to decide between IPTE for every PTE and lazy TLB
flushing with IDTE. That fixed the problem with mm_users but it
introduced another subtle race, fortunately one that is very hard
to hit.
The background is the requirement of the architecture that a valid
PTE may not be changed while it can be used concurrently by another
cpu. The decision between IPTE and lazy TLB flushing needs to be
done while the PTE is still valid. Now if the virtual cpu is
temporarily stopped after the decision to use lazy TLB flushing but
before the invalid bit of the PTE has been set, another cpu can attach
the mm, find that flush_mm is set, do the IDTE, return to userspace,
and recreate a TLB that uses the PTE in question. When the first,
stopped cpu continues it will change the PTE while it is attached on
another cpu. The first cpu will do another IDTE shortly after the
modification of the PTE which makes the race window quite short.

To fix this race the CPU that wants to attach the address space of a
user space thread needs to wait for the end of the PTE modification.
The number of concurrent TLB flushers for an mm is tracked in the
upper 16 bits of the attach_count and finish_arch_post_lock_switch
is used to wait for the end of the flush operation if required.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-21 08:50:18 +01:00
Heiko Carstens 7385d0a550 s390/uaccess: remove dead kernel parameter 'user_mode='
Remove another leftover from the time when we supported running
user space in either home or primary address space.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-21 08:50:16 +01:00
Heiko Carstens ca04ddbf53 s390/setup: get rid of MACHINE_HAS_MVCOS machine flag
MACHINE_HAS_MVCOS is used exactly once when the machine is brought up.
There is no need to cache the flag in the machine_flags.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-21 08:50:15 +01:00
Heiko Carstens 4f41c2b456 s390/uaccess: get rid of indirect function calls
There are only two uaccess variants on s390 left: the version that is used
if the mvcos instruction is available, and the page table walk variant.
So there is no need for expensive indirect function calls.

By default the mvcos variant will be called. If the mvcos instruction is not
available it will call the page table walk variant.

For minimal performance impact the "if (mvcos_is_available)" is implemented
with a jump label, which will be a six byte nop on machines with mvcos.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-21 08:50:14 +01:00
Heiko Carstens 423edb6fce s390/compat: fix sys_sched_getattr compat wrapper
Fix stupid typo.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-21 08:48:21 +01:00
Linus Torvalds a87af778d8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 bugfixes from Martin Schwidefsky:
 "A collection a bug fixes.  Most of them are minor but two of them are
  more severe.  The linkage stack bug can be used by user space to force
  an oops, with panic_on_oops this is a denial-of-service.  And the dump
  memory detection issue can cause incomplete memory dumps"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/cio: improve cio_commit_config
  s390: fix kernel crash due to linkage stack instructions
  s390/dump: Fix dump memory detection
  s390/appldata: restore missing init_virt_timer()
  s390/qdio: correct program-controlled interruption checking
  s390/qdio: for_each macro correctness
2014-02-11 12:23:50 -08:00
Martin Schwidefsky 8d7f6690ce s390: fix kernel crash due to linkage stack instructions
The kernel currently crashes with a low-address-protection exception
if a user space process executes an instruction that tries to use the
linkage stack. Set the base-ASTE origin and the subspace-ASTE origin
of the dispatchable-unit-control-table to point to a dummy ASTE.
Set up control register 15 to point to an empty linkage stack with no
room left.

A user space process with a linkage stack instruction will still crash
but with a different exception which is correctly translated to a
segmentation fault instead of a kernel oops.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-05 11:00:50 +01:00
Heiko Carstens 49382d9385 s390/compat: change parameter types from unsigned long to compat_ulong_t
Change parameter types of s390's compat ipc syscall from unsigned long
to compat_ulong_t to enforce zero extension of these parameters.

This is not really a bug, since s390_ipc compat syscall is only a
wrapper to the generic compat_sys_ipc() syscall, which performs correct
zero and sign extension.

This was introduced with commit 56e41d3c5a ("merge compat sys_ipc
instances").

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-29 16:22:40 -08:00
Heiko Carstens fded4329da s390: wire up sys_sched_setattr/sys_sched_getattr
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-01-22 14:02:19 +01:00
Linus Torvalds f479c01c8e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "The bulk of the s390 updates for v3.14.

  New features are the perf support for the CPU-Measurement Sample
  Facility and the EP11 support for the crypto cards.  And the normal
  cleanups and bug-fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (44 commits)
  s390/cpum_sf: fix printk format warnings
  s390: Fix misspellings using 'codespell' tool
  s390/qdio: bridgeport support - CHSC part
  s390: delete new instances of __cpuinit usage
  s390/compat: fix PSW32_USER_BITS definition
  s390/zcrypt: add support for EP11 coprocessor cards
  s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
  s390: use IS_ENABLED to check if a CONFIG is set to y or m
  s390/cio: use device_lock to synchronize calls to the ccwgroup driver
  s390/cio: use device_lock to synchronize calls to the ccw driver
  s390/cio: fix unlocked access of online member
  s390/cpum_sf: Add flag to process full SDBs only
  s390/cpum_sf: Add raw data sampling to support the diagnostic-sampling function
  s390/cpum_sf: Filter perf events based event->attr.exclude_* settings
  s390/cpum_sf: Detect KVM guest samples
  s390/cpum_sf: Add helper to read TOD from trailer entries
  s390/cpum_sf: Atomically reset trailer entry fields of sample-data-blocks
  s390/cpum_sf: Dynamically extend the sampling buffer if overflows occur
  s390/pci: reenable per default
  s390/pci/dma: fix accounting of allocated_pages
  ...
2014-01-20 09:23:31 -08:00
Hendrik Brueckner f85168e4d9 s390/cpum_sf: fix printk format warnings
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-01-16 16:40:16 +01:00
Hendrik Brueckner b4a960159e s390: Fix misspellings using 'codespell' tool
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-01-16 16:40:13 +01:00
Paul Gortmaker 28aa39b853 s390: delete new instances of __cpuinit usage
The patch "s390/perf: add support for the CPU-Measurement Sampling
Facility" added a new instance of the __cpuinit macro usage.

We removed this a couple versions ago; we now want to remove
the compat no-op stubs.  Introducing new users is not what
we want to see at this point in time, as it will break once
the stubs are gone.

Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-01-13 16:50:25 +01:00
Martin Schwidefsky 9efe4f2992 s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
Skip the call to brk_rnd() if the PF_RANDOMIZE flag is not set for
the process. This avoids the costly get_random_int() call. Modify
arch_randomize_brk() as well to make it look like randomize_et_dyn().

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-18 17:36:38 +01:00
Heiko Carstens d80512f874 s390/smp: improve setup of possible cpu mask
Since under z/VM we cannot have more than 64 cpus, make sure the
cpu_possible_mask does not contain more bits.
This avoids wasting memory for dynamic per-cpu allocations if
CONFIG_NR_CPUS is larger than 64.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-18 17:35:18 +01:00
Heiko Carstens 61aa4884b7 s390: use IS_ENABLED to check if a CONFIG is set to y or m
This is shorter and should be used instead of the longer form
which checks for both possible config options.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:38:04 +01:00
Hendrik Brueckner d7528862cf s390/cpum_sf: Add flag to process full SDBs only
Add the PERF_CPUM_SF_FULL_BLOCKS flag to process only sample-data-blocks that
have the block-full-indicator bit set.  Sample-data-blocks that are partially
filled are discarded.  Use this flag if the sampling buffer is likely to be
shared among perf events that use different sampling modes.  In such
environments, flushing sample-data-blocks that are not completely filled, might
cause invalid-data-formats.

Setting PERF_CPUM_SF_FULL_BLOCKS prevents potentially invalid sampling data to
be processed but, in contrast, also discards valid samples in partially filled
sample-data-blocks.  Note that sample-data-blocks might not become full for
small sampling frequencies or for workload that is scheduled for tiny intervals.

To sample with the PERF_CPUM_SF_FULL_BLOCKS flag, set the perf->attr.config1
to 0x0004.  For example:

	perf record -e cpum_sf/config=0xB000,config1=0x0004/

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:38:01 +01:00
Hendrik Brueckner 7e75fc3ff4 s390/cpum_sf: Add raw data sampling to support the diagnostic-sampling function
Also support the diagnostic-sampling function in addition to the basic-sampling
function.  Diagnostic-sampling data entries contain hardware model specific
sampling data and additional programs are required to analyze the data.

To deliver diagnostic-sampling, as well, as basis-sampling data entries to user
space, introduce support for sampling "raw data".  If this particular perf
sampling type (PERF_SAMPLE_RAW) is used, sampling data entries are copied
to user space.  External programs can then analyze these data.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:38:00 +01:00
Hendrik Brueckner dd127b3b97 s390/cpum_sf: Filter perf events based event->attr.exclude_* settings
Introduce the perf_exclude_event() function to filter perf samples
according to event->attr.exclude_* settings.   During event initialization,
reset event exclude settings that are not supported.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:59 +01:00
Hendrik Brueckner 443e802bab s390/cpum_sf: Detect KVM guest samples
The host-program-parameter (hpp) value of basic sample-data-entries designates
a SIE control block that is set by the LPP instruction in sie64a().
Non-zero values indicate guest samples, a value of zero indicates a host sample.

For perf samples, host and guest samples are distinguished using particular
PERF_MISC_* flags.  The perf layer calls perf_misc_flags() to set the flags
based on the pt_regs content.  For each sample-data-entry, the cpum_sf PMU
creates a pt_regs structure with the sample-data information.  An additional
flag structure is added to easily distinguish between host and guest samples.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:59 +01:00
Hendrik Brueckner 443d4beb82 s390/cpum_sf: Add helper to read TOD from trailer entries
The trailer entry contains a timestamp of the time when the sample-data-block
became full.  The timestamp specifies a TOD (time-of-day) value in either the
STCK or STCKE format.

Provide a helper function to return the TOD value depending on the setting of
time format indicator.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:58 +01:00
Hendrik Brueckner fcc77f5073 s390/cpum_sf: Atomically reset trailer entry fields of sample-data-blocks
Ensure to reset the sample-data-block full indicator and the overflow counter
at the same time.  This must be done atomically because the sampling hardware
is still active while full sample-data-block is processed.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:57 +01:00
Hendrik Brueckner 69f239ed33 s390/cpum_sf: Dynamically extend the sampling buffer if overflows occur
Improve the sampling buffer allocation and add a function to reallocate and
increase the sampling buffer structure.  The number of allocated buffer elements
(sample-data-blocks) are accounted.  You can control the minimum and maximum
number these sample-data-blocks through the cpum_sfb_size kernel parameter.

The number hardware sample overflows (if any) are also accounted and stored
per perf event.  During the PMU disable/enable calls, the accumulated overflow
counter is analyzed and, if necessary, the sampling buffer is dynamically
increased.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:57 +01:00
Hendrik Brueckner 99c64b6679 s390/perf: Add service level information for CPU-Measurement Facilities
Register a service level handler to report information about available
CPU-Measurement facilities.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:53 +01:00
Hendrik Brueckner e28bb79d99 s390/perf,oprofile: Share sampling facility
Introduce reserve/release functions to share the sampling facility
between perf and oprofile.
Also improve error handling for the sampling facility support in perf.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:52 +01:00
Hendrik Brueckner 55baa2f831 s390/perf: Improve PMU selection for PERF_COUNT_HW_CPU_CYCLES events
The cpum_cf (counter facility) PMU does not support sampling events.
With cpum_sf (sampling facility), a PMU for sampling CPU cycles is
available.

Make cpum_sf the "default" PMU for PERF_COUNT_HW_CPU_CYCLES sampling
events but use the more precise cpum_cf PMU for non-sampling events.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:52 +01:00
Hendrik Brueckner 8c069ff4bd s390/perf: add support for the CPU-Measurement Sampling Facility
Introduce a perf PMU, "cpum_sf", to support the CPU-Measurement
Sampling Facility.  You can control the sampling facility through
this perf PMU interfaces.  Perf sampling events are created for
hardware samples.

For details about the CPU-Measurement Sampling Facility, see
"The Load-Program-Parameter and the CPU-Measurement Facilities" (SA23-2260).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:51 +01:00
Hendrik Brueckner c716832513 s390/cpum_cf: Export event names in sysfs
Provide PMU event attributes for supported counters and export their symbolic
names to the sysfs "events" directory.

See the /sys/devices/cpum_cf/events/ directory for a list of available counters.
Note that you might require counter set authorizations for the LPAR to use them.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:50 +01:00
Martin Schwidefsky 41932bc1c8 s390/compat: correct check for EFAULT in rt-signal frame creation
The return code of the __put_user call to store the rt_sigreturn
system call to the user stack if not properly checked, the err
variable is only checked before to the __put_user. Use an if
statement instead.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:47 +01:00
Heiko Carstens 96619fc1b3 s390/smp: reduce memory consumption of pcpu_devices array
Remove the embedded struct cpu from struct pcpu and replace it with a
pointer instead. The struct cpu now gets allocated when a new cpu gets
detected.

The size of the pcpu_devices array (NR_CPUS * sizeof(struct pcpu)) gets
reduced by nearly 120KB.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:46 +01:00
Martin Schwidefsky c63badebfe s390: optimize control register update
It is less expensive to update control registers 0 and 2 with two
individual stctg/lctlg instructions as with a single one that spans
control register 0, 1 and 2.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:45 +01:00
Martin Schwidefsky 1c182a6280 s390/ptrace: simplify enable/disable single step
The user_enable_single_step() and user_disable_sindle_step() functions
are always called on the inferior, never for the currently active
process. Remove the unnecessary check for the current process and
the update_cr_regs() call from the enable/disable functions.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:44 +01:00
Heiko Carstens dea24190fb s390/smp: only send external call ipi if needed
If the per cpu ec_mask bit of the receiving cpu is already set there is
no need to send an ipi, since a different cpu has already sent an ipi
and the receiving cpu has not yet executed the external call ipi handler.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:43 +01:00
Martin Schwidefsky ca5de58ba7 s390/time,vdso: fix clock_gettime for CLOCK_MONOTONIC
With git commit 79c74ecbeb
"s390/time,vdso: convert to the new update_vsyscall interface"
the new update_vsyscall function already does the sum of xtime
and wall_to_monotonic. The old update_vsyscall function only
copied the wall_to_monotonic offset. The vdso code needs to be
modified to take this into consideration.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-02 18:15:25 +01:00
Martin Schwidefsky b5e64b3de7 s390/vdso: ectg gettime support for CLOCK_THREAD_CPUTIME_ID
The code to use the ECTG instruction to calculate the cputime for the
current thread is currently used only for the per-thread CPU-clock
with the clockid -2 (PID=0, VIRT=1). Use the same code for the clockid
CLOCK_THREAD_CPUTIME_ID to speed up the more common clockid as well.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-02 15:31:10 +01:00
Heiko Carstens 06aae6834e s390/vdso: fix access-list entry initialization
The access-list entry is supposed to have the fetch-only bit set, however
a reserved bit got set instead.
Userspace isn't able to write to the page anyway since the accessed page
has the read-only bit set. So this saves us only for bad surprises in the
future if the reserved bit gets used.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-02 15:31:09 +01:00
Martin Schwidefsky 127581b64b s390/mm: handle asce-type exceptions as normal page fault
Git commit 9e34f2686bb088b211b6cac8772e1f644c6180f8
"s390/mm,tlb: tlb flush on page table upgrade fixup" removed the
exception handler for the asce-type exception. This is incorrect
as the user-copy with MVCOS can cause asce-type exceptions in
the kernel if a user pointer is too large. Those need to be
handled with do_no_context to branch to the fixup in the
user-copy code.

The simplest fix for this problem is to call do_dat_exception for
asce-type excpetions, as there is no vma for the address the code
will handle the exception correctly.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-25 09:15:42 +01:00
Martin Schwidefsky 8adbf78ec4 s390,time: revert direct ktime path for s390 clockevent device
Git commit 4f37a68cda
"s390: Use direct ktime path for s390 clockevent device" makes use
of the CLOCK_EVT_FEAT_KTIME clockevent option to avoid the delta
calculation with ktime_get() in clockevents_program_event and the
get_tod_clock() in s390_next_event. This is based on the assumption
that the difference between the internal ktime and the hardware
clock is reflected in the wall_to_monotonic delta. But this is not
true, the ntp corrections are applied via changes to the tk->mult
multiplier and this is not reflected in wall_to_monotonic.

In theory this could be solved by using the raw monotonic clock
but it is simpler to switch back to the standard clock delta
calculation.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-25 09:15:41 +01:00
Martin Schwidefsky 79c74ecbeb s390/time,vdso: convert to the new update_vsyscall interface
Switch to the improved update_vsyscall interface that provides
sub-nanosecond precision for gettimeofday and clock_gettime.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-25 09:15:39 +01:00
Hendrik Brueckner aa7e04b380 s390/signal: always restore saved runtime instrumentation psw bit
Commit "s390: fix handling of runtime instrumentation psw bit" (5ebf250dab)
changed the behavior of setting the runtime instrumentation psw bit.  This
commit restores the original logic:

1. When returning from the signal handler, the runtime instrumentation psw bit
   is restored to its saved state.
2. If the runtime instrumentation psw bit is enabled during the signal handler,
   it is always turned off when leaving the signal handler.  The saved state
   is restored as described in 1.  That also implies that turning on runtime
   instrumentation in the signal handler is only effective while running in the
   signal context.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
2013-11-20 09:04:53 +01:00
Linus Torvalds 806dace637 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull second set of s390 patches from Martin Schwidefsky:
 "The handling of the PCI hotplug notifications has been improved, the
  zfcp dumper can now detect the HSA size dynamically and the default
  install kernel has been changed to the compressed bzImage.  And two
  bug-fixes for scm and 3720"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pci: implement hotplug notifications
  s390/scm_block: do not hide eadm subchannel dependency
  s390/sclp: Consolidate early sclp init calls to sclp_early_detect()
  s390/sclp: Move early code from sclp_cmd.c to sclp_early.c
  s390/sclp: Determine HSA size dynamically for zfcpdump
  s390/sclp: Move declarations for sclp_sdias into separate header file
  s390/pci: implement pcibios_remove_bus
  s390/pci: improve handling of bus resources
  s390/3270: fix missing device_destroy() call
  s390/boot: Install bzImage as default kernel image
2013-11-19 11:43:21 -08:00
Linus Torvalds 9073e1a804 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "Usual earth-shaking, news-breaking, rocket science pile from
  trivial.git"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
  doc: add missing files to timers/00-INDEX
  timekeeping: Fix some trivial typos in comments
  mm: Fix some trivial typos in comments
  irq: Fix some trivial typos in comments
  NUMA: fix typos in Kconfig help text
  mm: update 00-INDEX
  doc: Documentation/DMA-attributes.txt fix typo
  DRM: comment: `halve' -> `half'
  Docs: Kconfig: `devlopers' -> `developers'
  doc: typo on word accounting in kprobes.c in mutliple architectures
  treewide: fix "usefull" typo
  treewide: fix "distingush" typo
  mm/Kconfig: Grammar s/an/a/
  kexec: Typo s/the/then/
  Documentation/kvm: Update cpuid documentation for steal time and pv eoi
  treewide: Fix common typo in "identify"
  __page_to_pfn: Fix typo in comment
  Correct some typos for word frequency
  clk: fixed-factor: Fix a trivial typo
  ...
2013-11-15 16:47:22 -08:00
Michael Holzheu 7b50da53f6 s390/sclp: Consolidate early sclp init calls to sclp_early_detect()
The new function calls the old ones. The sclp_event_mask_early() is removed
and replaced by one invocation of sclp_set_event_mask(0, 0).

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>
2013-11-15 14:08:41 +01:00
Michael Holzheu e657d8fe2f s390/sclp: Determine HSA size dynamically for zfcpdump
Currently we have hardcoded the HSA size to 32 MiB. With this patch the
HSA size is determined dynamically via SCLP in early.c.

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>
2013-11-15 14:08:40 +01:00
Linus Torvalds 5cbb3d216e Merge branch 'akpm' (patches from Andrew Morton)
Merge first patch-bomb from Andrew Morton:
 "Quite a lot of other stuff is banked up awaiting further
  next->mainline merging, but this batch contains:

   - Lots of random misc patches
   - OCFS2
   - Most of MM
   - backlight updates
   - lib/ updates
   - printk updates
   - checkpatch updates
   - epoll tweaking
   - rtc updates
   - hfs
   - hfsplus
   - documentation
   - procfs
   - update gcov to gcc-4.7 format
   - IPC"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (269 commits)
  ipc, msg: fix message length check for negative values
  ipc/util.c: remove unnecessary work pending test
  devpts: plug the memory leak in kill_sb
  ./Makefile: export initial ramdisk compression config option
  init/Kconfig: add option to disable kernel compression
  drivers: w1: make w1_slave::flags long to avoid memory corruption
  drivers/w1/masters/ds1wm.cuse dev_get_platdata()
  drivers/memstick/core/ms_block.c: fix unreachable state in h_msb_read_page()
  drivers/memstick/core/mspro_block.c: fix attributes array allocation
  drivers/pps/clients/pps-gpio.c: remove redundant of_match_ptr
  kernel/panic.c: reduce 1 byte usage for print tainted buffer
  gcov: reuse kbasename helper
  kernel/gcov/fs.c: use pr_warn()
  kernel/module.c: use pr_foo()
  gcov: compile specific gcov implementation based on gcc version
  gcov: add support for gcc 4.7 gcov format
  gcov: move gcov structs definitions to a gcc version specific file
  kernel/taskstats.c: return -ENOMEM when alloc memory fails in add_del_listener()
  kernel/taskstats.c: add nla_nest_cancel() for failure processing between nla_nest_start() and nla_nest_end()
  kernel/sysctl_binary.c: use scnprintf() instead of snprintf()
  ...
2013-11-13 15:45:43 +09:00
Linus Torvalds 9bc9ccd7db Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "All kinds of stuff this time around; some more notable parts:

   - RCU'd vfsmounts handling
   - new primitives for coredump handling
   - files_lock is gone
   - Bruce's delegations handling series
   - exportfs fixes

  plus misc stuff all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
  ecryptfs: ->f_op is never NULL
  locks: break delegations on any attribute modification
  locks: break delegations on link
  locks: break delegations on rename
  locks: helper functions for delegation breaking
  locks: break delegations on unlink
  namei: minor vfs_unlink cleanup
  locks: implement delegations
  locks: introduce new FL_DELEG lock flag
  vfs: take i_mutex on renamed file
  vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
  vfs: don't use PARENT/CHILD lock classes for non-directories
  vfs: pull ext4's double-i_mutex-locking into common code
  exportfs: fix quadratic behavior in filehandle lookup
  exportfs: better variable name
  exportfs: move most of reconnect_path to helper function
  exportfs: eliminate unused "noprogress" counter
  exportfs: stop retrying once we race with rename/remove
  exportfs: clear DISCONNECTED on all parents sooner
  exportfs: more detailed comment for path_reconnect
  ...
2013-11-13 15:34:18 +09:00
Jianguo Wu 40c3baa7c6 mm/arch: use NUMA_NO_NODE
Use more appropriate NUMA_NO_NODE instead of -1 in all archs' module_alloc()

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:05 +09:00
Linus Torvalds 1006fae359 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull IRQ changes from Ingo Molnar:
 "The biggest change this cycle are the softirq/hardirq stack
  interaction and nesting fixes, cleanups and reorganizations from
  Frederic.  This is the longer followup story to the softirq nesting
  fix that is already upstream (commit ded797547548: "irq: Force hardirq
  exit's softirq processing on its own stack")"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: bcm2835: Convert to use IRQCHIP_DECLARE macro
  powerpc: Tell about irq stack coverage
  x86: Tell about irq stack coverage
  irq: Optimize softirq stack selection in irq exit
  irq: Justify the various softirq stack choices
  irq: Improve a bit softirq debugging
  irq: Optimize call to softirq on hardirq exit
  irq: Consolidate do_softirq() arch overriden implementations
  x86/irq: Correct comment about i8259 initialization
2013-11-12 10:02:59 +09:00
Al Viro ce39596048 constify copy_siginfo_to_user{,32}()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:29 -05:00
Martin Schwidefsky 106078641f s390/mm,tlb: correct tlb flush on page table upgrade
The IDTE instruction used to flush TLB entries for a specific address
space uses the address-space-control element (ASCE) to identify
affected TLB entries. The upgrade of a page table adds a new top
level page table which changes the ASCE. The TLB entries associated
with the old ASCE need to be flushed and the ASCE for the address space
needs to be replaced synchronously on all CPUs which currently use it.
The concept of a lazy ASCE update with an exception handler is broken.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-04 13:51:47 +01:00
Martin Schwidefsky 4560e7c331 s390/vtime: correct idle time calculation
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>
2013-10-31 09:52:52 +01:00
Joe Perches 302bfe20ad s390: convert use of typedef ctl_table to struct ctl_table
This typedef is unnecessary and should just be removed.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-28 08:36:25 +01:00
Heiko Carstens f26946d7ec s390/compat: make psw32_user_bits a constant value again
Make psw32_user_bits a constant value again.
This is a leftover of the code which allowed to run the kernel either
in primary or home space which got removed with 9a905662 "s390/uaccess:
always run the kernel in home space".

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:12 +02:00
Heiko Carstens 5ebf250dab s390: fix handling of runtime instrumentation psw bit
Fix the following bugs:
- When returning from a signal the signal handler copies the saved psw mask
  from user space and uses parts of it. Especially it restores the RI bit
  unconditionally. If however the machine doesn't support RI, or RI is
  disabled for the task, the last lpswe instruction which returns to user
  space will generate a specification exception.
  To fix this check if the RI bit is allowed to be set and kill the task
  if not.
- In the compat mode signal handler code the RI bit of the psw mask gets
  propagated to the mask of the return psw: if user space enables RI in the
  signal handler, RI will also be enabled after the signal handler is
  finished.
  This is a different behaviour than with 64 bit tasks. So change this to
  match the 64 bit semantics, which restores the original RI bit value.
- Fix similar oddities within the ptrace code as well.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:11 +02:00
Martin Schwidefsky 4725c86055 s390: fix save and restore of the floating-point-control register
The FPC_VALID_MASK has been used to check the validity of the value
to be loaded into the floating-point-control register. With the
introduction of the floating-point extension facility and the
decimal-floating-point additional bits have been defined which need
to be checked in a non straight forward way. So far these bits have
been ignored which can cause an incorrect results for decimal-
floating-point operations, e.g. an incorrect rounding mode to be
set after signal return.

The static check with the FPC_VALID_MASK is replaced with a trial
load of the floating-point-control value, see test_fp_ctl.

In addition an information leak with the padding word between the
floating-point-control word and the floating-point registers in
the s390_fp_regs is fixed.

Reported-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>
2013-10-24 17:17:11 +02:00
Heiko Carstens 160d378ebc s390/cache: get rid of compile warning
Get rid of this one:

arch/s390/kernel/cache.c: In function 'cache_build_info':
arch/s390/kernel/cache.c:144: warning: 'private' may be used uninitialized
in this function

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:06 +02:00
Heiko Carstens f8544ec4f4 s390/compat,signal: change return values to -EFAULT
Instead of returnin the number of bytes not copied and/or -EFAULT let the
signal handler helper functions always return -EFAULT if a user space
access failed.
This doesn't fix a bug in the current code, but makes is harder to get it
wrong in the future.
Also "smatch" won't complain anymore about the fact that the number of
remaining bytes gets returned instead of -EFAULT.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:06 +02:00
Michael Holzheu 5895294274 s390: Remove zfcpdump NR_CPUS dependency
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>
2013-10-24 17:17:04 +02:00
Heiko Carstens 05e0baaf9b s390/ftrace: prepare_ftrace_return() function call order
Steven Rostedt noted that s390 is the only architecture which calls
ftrace_push_return_trace() before ftrace_graph_entry() and therefore has
the small advantage that trace.depth gets initialized automatically.

However this small advantage isn't worth the difference and possible subtle
breakage that may result from this.
So change s390 to have the same function call order like all other
architectures: first ftrace_graph_entry(), then ftrace_push_return_trace()

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:03 +02:00
Heiko Carstens 5ff4212f19 s390/crashdump: remove unused variable
Get rid of this compile warning:

arch/s390/kernel/crash_dump.c: In function 'copy_from_realmem':
arch/s390/kernel/crash_dump.c:48:6: warning: unused variable 'rc'
[-Wunused-variable]
  int rc;
      ^

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:02 +02:00
Martin Schwidefsky 127c1fefff s390/mm: do not initialize storage keys
With dirty and referenced bits implemented in software it is unnecessary
to initialize the storage key for every page. With this patch not a single
storage key operation is done for a system that does not use KVM.
For KVM set_pte_at/pgste_set_key will do the initialization for the guest
view of the storage key when the mapping for the page is established in
the host.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:00 +02:00
Martin Schwidefsky e258d719ff s390/uaccess: always run the kernel in home space
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>
2013-10-24 17:16:57 +02:00
Heiko Carstens 746479cdcb s390/bitops: use generic find bit functions / reimplement _left variant
Just like all other architectures we should use out-of-line find bit
operations, since the inline variant bloat the size of the kernel image.
And also like all other architecures we should only supply optimized
variants of the __ffs, ffs, etc. primitives.

Therefore this patch removes the inlined s390 find bit functions and uses
the generic out-of-line variants instead.

The optimization of the primitives follows with the next patch.

With this patch also the functions find_first_bit_left() and
find_next_bit_left() have been reimplemented, since logically, they are
nothing else but a find_first_bit()/find_next_bit() implementation that
use an inverted __fls() instead of __ffs().
Also the restriction that these functions only work on machines which
support the "flogr" instruction is gone now.

This reduces the size of the kernel image (defconfig, -march=z9-109)
by 144,482 bytes.
Alone the size of the function build_sched_domains() gets reduced from
7 KB to 3,5 KB.

We also git rid of unused functions like find_first_bit_le()...

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:55 +02:00
Heiko Carstens 4ae803253e s390/bitops: optimize set_bit() for constant values
Since zEC12 we have the interlocked-access facility 2 which allows to
use the instructions ni/oi/xi to update a single byte in storage with
compare-and-swap semantics.
So change set_bit(), clear_bit() and change_bit() to generate such code
instead of a compare-and-swap loop (or using the load-and-* instruction
family), if possible.
This reduces the text segment by yet another 8KB (defconfig).

Alternatively the long displacement variants niy/oiy/xiy could have
been used, but the extended displacement field is usually not needed
and therefore would only increase the size of the text segment again.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:53 +02:00
Heiko Carstens 370b0b5f77 s390/bitops: remove CONFIG_SMP / simplify non-atomic bitops
Remove CONFIG_SMP from bitops code. This reduces the C code significantly
but also generates better code for the SMP case.

This means that for !CONFIG_SMP set_bit() and friends now also have
compare and swap semantics (read: more code). However nobody really cares
for !CONFIG_SMP and this is the trade-off to simplify the SMP code which we
do care about.

The non-atomic bitops like __set_bit() now generate also better code
because the old code did not have a __builtin_contant_p() check for the
CONFIG_SMP case and therefore always generated the inline assembly variant.
However the inline assemblies for the non-atomic case now got completely
removed since gcc can produce better code, which accesses less memory
operands.

test_bit() got also a bit simplified since it did have a
__builtin_constant_p() check, however two identical code pathes for each
case (written differently).

In result this mainly reduces the to be maintained code but is not very
relevant for code generation, since there are not many non-atomic bitops
usages that we care about.
(code reduction defconfig kernel image before/after: 560 bytes).

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:52 +02:00
Heiko Carstens 1ffa11abfe s390/kprobes: allow kprobes only on known instructions
Since we have an in-kernel disassembler we can make sure that
there won't be any kprobes set on random data.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:50 +02:00
Heiko Carstens a882b3b067 s390/kprobes: use insn_length helper function
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:49 +02:00
Heiko Carstens 0f20822a69 s390/dis: move disassembler function prototypes to proper header file
Now that the in-kernel disassembler has an own header file move the
disassembler related function prototypes to that header file.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:48 +02:00
Suzuki K. Poulose 648ae35c54 s390/dis: move common definitions to a header file
The patch moves some of the definitions to a
header file. No functional changes involved.

I have retained the Copyright Statement from the
original file.

Signed-off-by: Suzuki K Poulose <suzuki@in.ibm.com>
[Heiko Carstens: rename s390-dis.h to dis.h]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:48 +02:00
Suzuki K. Poulose f616d67607 s390/dis: rename structures for unique types
Rename 'insn' and 'operand' structures to more canonical names
to avoid conflicts.

struct insn represents information about an instruction, including
the mnemonics, format and opcode.

struct operand represents the 'properties' and information on howto
interpret the operand value and doesn't contain the value.

We rename these structures for avoiding a global conflict.

i.e,

1,$s/struct insn/struct s390_insn/g
1,$s/struct operand/struct s390_operand/g

Signed-off-by: Suzuki K Poulose <suzuki@in.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:47 +02:00
Heiko Carstens fcd05b50fc s390/kprobes: have more correct if statement in s390_get_insn_slot()
When checking the insn address wether it is a kernel image or module
address it should be an if-else-if statement not two independent if
statements.
This doesn't really fix a bug, but matches s390_free_insn_slot().

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:16:45 +02:00
Martin Schwidefsky 8c071b0f19 s390/time: correct use of store clock fast
The result of the store-clock-fast (STCKF) instruction is a bit fuzzy.
It can happen that the value stored on one CPU is smaller than the value
stored on another CPU, although the order of the stores is the other
way around. This can cause deltas of get_tod_clock() values to become
negative when they should not be.

We need to be more careful with store-clock-fast, this patch partially
reverts git commit e4b7b4238e666682555461fa52eecd74652f36bb "time:
always use stckf instead of stck if available". The get_tod_clock()
function now uses the store-clock-extended (STCKE) instruction.
get_tod_clock_fast() can be used if the fuzziness of store-clock-fast
is acceptable e.g. for wait loops local to a CPU.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-22 09:16:40 +02:00
Heiko Carstens 0ebfd313fd s390/compat,signal: fix return value of copy_siginfo_(to|from)_user32()
The return value of copy_siginfo_(to|from)_user32() gets passed to
user space, however we do not convert a positive return value from
copy_(to|from)_user to -EFAULT.
Therefore these functions (and the calling system calls) my incorrectly
return a positive number (bytes not copied) instead of -EFAULT.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-15 13:47:59 +02:00