linux-toradex.git/arch/s390/lib, branch v3.4.78

[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 warnings with __user pointers

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

Use __force to quiet sparse warnings about user address space.

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

[S390] fix s390 assembler code alignments

2011-07-24T08:48:21+00:00

The alignment is missing for various global symbols in s390 assembly code.
With a recent gcc and an instruction like stgrl this can lead to a
specification exception if the instruction uses such a mis-aligned address.

Specify the alignment explicitely and while add it define __ALIGN for s390
and use the ENTRY define to save some lines of code.

Signed-off-by: Jan Glauber 
Signed-off-by: Martin Schwidefsky

[S390] delay: implement ndelay

2011-05-26T07:48:25+00:00

Implement ndelay() on s390 as well.

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

futex: Sanitize futex ops argument types

2011-03-11T11:23:31+00:00

Change futex_atomic_op_inuser and futex_atomic_cmpxchg_inatomic
prototypes to use u32 types for the futex as this is the data type the
futex core code uses all over the place.

Signed-off-by: Michel Lespinasse 
Cc: Darren Hart 
Cc: Peter Zijlstra 
Cc: Matt Turner 
Cc: Russell King 
Cc: David Howells 
Cc: Tony Luck 
Cc: Michal Simek 
Cc: Ralf Baechle 
Cc: "James E.J. Bottomley" 
Cc: Benjamin Herrenschmidt 
Cc: Martin Schwidefsky 
Cc: Paul Mundt 
Cc: "David S. Miller" 
Cc: Chris Metcalf 
Cc: Linus Torvalds 
LKML-Reference: <20110311025058.GD26122@google.com>
Signed-off-by: Thomas Gleixner

futex: Sanitize cmpxchg_futex_value_locked API

2011-03-11T11:23:08+00:00

The cmpxchg_futex_value_locked API was funny in that it returned either
the original, user-exposed futex value OR an error code such as -EFAULT.
This was confusing at best, and could be a source of livelocks in places
that retry the cmpxchg_futex_value_locked after trying to fix the issue
by running fault_in_user_writeable().
    
This change makes the cmpxchg_futex_value_locked API more similar to the
get_futex_value_locked one, returning an error code and updating the
original value through a reference argument.
    
Signed-off-by: Michel Lespinasse 
Acked-by: Chris Metcalf   [tile]
Acked-by: Tony Luck   [ia64]
Acked-by: Thomas Gleixner 
Tested-by: Michal Simek   [microblaze]
Acked-by: David Howells  [frv]
Cc: Darren Hart 
Cc: Peter Zijlstra 
Cc: Matt Turner 
Cc: Russell King 
Cc: Ralf Baechle 
Cc: "James E.J. Bottomley" 
Cc: Benjamin Herrenschmidt 
Cc: Martin Schwidefsky 
Cc: Paul Mundt 
Cc: "David S. Miller" 
Cc: Linus Torvalds 
LKML-Reference: <20110311024851.GC26122@google.com>
Signed-off-by: Thomas Gleixner

[S390] missing sacf in uaccess

2011-01-31T10:30:20+00:00

The uaccess functions copy_in_user_std and clear_user_std fail to
switch back from secondary space mode to primary space mode with sacf
in case of an unresolvable page fault. We need to make sure that the
switch back to primary mode is done in all cases, otherwise the code
following the uaccess inline assembly will crash.

Reported-by: Alexander Graf 
Signed-off-by: Martin Schwidefsky

[S390] time: let local_tick_enable/disable() reprogram the clock comparator

2011-01-05T11:47:25+00:00

Let local_tick_enable/disable() reprogram the clock comparator so the
function names make semantically more sense.
Also that way the functions are more symmetric since normally each
local_tick_enable() call usually would have a subsequent call to
set_clock_comparator() anyway.

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