linux-stable.git/arch/s390/kernel/vtime.c, branch linux-3.7.y

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2012-10-01T18:49:56+00:00

Pull s390 updates from Martin Schwidefsky:
 "The main new feature is machine support for System zEC12 including
  transactional memory, runtime instrumentation, support for scm block
  devices via eadm subchannels, and support for CEX4 crypto cards.

  In addition there are some nice improvements: bpf jit compiler, arch
  backend for cmpxchg_double, relative exception table entries, dasd
  partition detection independent from the dasd driver ioctls, and cpu
  cache information in /proc/cpuinfo and /sys/device/cpu.

  And last but not least a series of cleanup patches from Heiko."

Fix up trivial add-add conflict in arch/s390/Kconfig due to commit
b952741c8079 ("cputime: Generalize CONFIG_VIRT_CPU_ACCOUNTING")

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (76 commits)
  s390: update defconfig
  s390/jump label,nss: let shared kernel support depend on !JUMP_LABEL
  s390/disassembler: fix decoding of risblg instruction
  s390/bpf,jit: add support for BPF_S_ANC_ALU_XOR_X instruction
  s390/traps: move call to print_modules() out of show_regs()
  s390/mm: mark free_initrd_mem() as __init
  s390/dasd: check count address during online setting
  drivers/s390/char/monreader.c: fix error return code
  s390/cmpxchg,percpu: implement cmpxchg_double()
  s390/percpu: implement this_cpu_add_return()
  s390/percpu: implement this_cpu_xchg()
  s390/kexec: remove CONFIG_KEXEC
  s390/irq: use designated initializers for irq class array
  s390: add uninitialized_var() to suppress false positive compiler warnings
  s390/crashdump: move fill_cpu_elf_notes() prototype to header file
  s390/process: add missing header include
  s390/ptrace: add missing ifdef
  s390/ipl,decrompressor: disable branch profiling
  s390/perf_events: compile only for CONFIG_64BIT
  s390/tape: remove even more tape block leftovers
  ...

s390/cpu hotplug: mask out CPU_TASKS_FROZEN in cu hotplug notifiers

2012-09-26T13:44:53+00:00

Unify all our cpu hotplug notifiers to mask out the CPU_TASKS_FROZEN
bit, so we don't have to add all the *_FROZEN variant cases to the
notifiers.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

cputime: Use a proper subsystem naming for vtime related APIs

2012-09-25T13:31:31+00:00

Use a naming based on vtime as a prefix for virtual based
cputime accounting APIs:

- account_system_vtime() -> vtime_account()
- account_switch_vtime() -> vtime_task_switch()

It makes it easier to allow for further declension such
as vtime_account_system(), vtime_account_idle(), ... if we
want to find out the context we account to from generic code.

This also make it better to know on which subsystem these APIs
refer to.

Signed-off-by: Frederic Weisbecker 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Heiko Carstens 
Cc: Martin Schwidefsky 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Peter Zijlstra

cputime: Consolidate vtime handling on context switch

2012-08-20T11:05:28+00:00

The archs that implement virtual cputime accounting all
flush the cputime of a task when it gets descheduled
and sometimes set up some ground initialization for the
next task to account its cputime.

These archs all put their own hooks in their context
switch callbacks and handle the off-case themselves.

Consolidate this by creating a new account_switch_vtime()
callback called in generic code right after a context switch
and that these archs must implement to flush the prev task
cputime and initialize the next task cputime related state.

Signed-off-by: Frederic Weisbecker 
Acked-by: Martin Schwidefsky 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Heiko Carstens 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Peter Zijlstra

s390/vtimer: rework virtual timer interface

2012-07-20T09:15:08+00:00

The current virtual timer interface is inherently per-cpu and hard to
use. The sole user of the interface is appldata which uses it to execute
a function after a specific amount of cputime has been used over all cpus.

Rework the virtual timer interface to hook into the cputime accounting.
This makes the interface independent from the CPU timer interrupts, and
makes the virtual timers global as opposed to per-cpu.
Overall the code is greatly simplified. The downside is that the accuracy
is not as good as the original implementation, but it is still good enough
for appldata.

Reviewed-by: Jan Glauber 
Reviewed-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

[S390] irq: external interrupt code passing

2012-03-11T15:59:29+00:00

The external interrupt handlers have a parameter called ext_int_code.
Besides the name this paramter does not only contain the ext_int_code
but in addition also the "cpu address" (POP) which caused the external
interrupt.
To make the code a bit more obvious pass a struct instead so the called
function can easily distinguish between external interrupt code and
cpu address. The cpu address field however is named "subcode" since
some external interrupt sources do not pass a cpu address but a
different parameter (or none at all).

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

[S390] rework idle code

2012-03-11T15:59:28+00:00

Whenever the cpu loads an enabled wait PSW it will appear as idle to the
underlying host system. The code in default_idle calls vtime_stop_cpu
which does the necessary voodoo to get the cpu time accounting right.
The udelay code just loads an enabled wait PSW. To correct this rework
the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts
to entry[64].S, vtime_stop_cpu can now be called from anywhere and
vtime_start_cpu is gone. The correction of the cpu time during wakeup
from an enabled wait PSW is done with a critical section in entry[64].S.
As vtime_start_cpu is gone, s390_idle_check can be removed as well.

Signed-off-by: Martin Schwidefsky

[S390] rework smp code

2012-03-11T15:59:28+00:00

Define struct pcpu and merge some of the NR_CPUS arrays into it, including
__cpu_logical_map, current_set and smp_cpu_state. Split smp related
functions to those operating on physical cpus and the functions operating
on a logical cpu number. Make the functions for physical cpus use a
pointer to a struct pcpu. This hides the knowledge about cpu addresses in
smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header.

The PSW restart mechanism is used to start secondary cpus, calling a
function on an online cpu, calling a function on the ipl cpu, and for
the nmi signal. Replace the different assembler functions with a
single function restart_int_handler. The new entry point calls a function
whose pointer is stored in the lowcore of the target cpu and it can wait
for the source cpu to stop. This covers all existing use cases.

Overall the code is now simpler and there are ~380 lines less code.

Reviewed-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

[S390] sparse: fix sparse static warnings

2011-10-30T14:16:46+00:00

Make functions and data static to avoid sparse warnings.

Signed-off-by: Martin Schwidefsky

[S390] cleanup psw related bits and pieces

2011-10-30T14:16:43+00:00

Split out addressing mode bits from PSW_BASE_BITS, rename PSW_BASE_BITS
to PSW_MASK_BASE, get rid of psw_user32_bits, remove unused function
enabled_wait(), introduce PSW_MASK_USER, and drop PSW_MASK_MERGE macros.
Change psw_kernel_bits / psw_user_bits to contain only the bits that
are always set in the respective mode.

Signed-off-by: Martin Schwidefsky