linux-stable.git/arch/s390/include/asm/setup.h, branch linux-4.4.y

s390/cpumf: rework program parameter setting to detect guest samples

2015-10-14T12:32:12+00:00

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

s390/entry: add assembler macro to conveniently tests under mask

2015-10-14T12:32:09+00:00

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

s390: remove 31 bit support

2015-03-25T10:49:33+00:00

Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.

The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.

Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.

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

s390/spinlock: add compare-and-delay to lock wait loops

2015-01-23T14:17:04+00:00

Add the compare-and-delay instruction to the spin-lock and rw-lock
retry loops. A CPU executing the compare-and-delay instruction stops
until the lock value has changed. This is done to make the locking
code for contended locks to behave better in regard to the multi-
hreading facility. A thread of a core executing a compare-and-delay
will allow the other threads of a core to get a larger share of the
core resources.

Signed-off-by: Martin Schwidefsky

s390: add support for vector extension

2014-10-09T07:14:13+00:00

The vector extension introduces 32 128-bit vector registers and a set of
instruction to operate on the vector registers.

The kernel can control the use of vector registers for the problem state
program with a bit in control register 0. Once enabled for a process the
kernel needs to retain the content of the vector registers on context
switch. The signal frame is extended to include the vector registers.
Two new register sets NT_S390_VXRS_LOW and NT_S390_VXRS_HIGH are added
to the regset interface for the debugger and core dumps.

Signed-off-by: Martin Schwidefsky

s390: remove unused MACHINE_FLAG_RRBM

2014-09-09T06:53:26+00:00

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

s390/mm: Convert bootmem to memblock

2014-05-20T06:58:40+00:00

The original bootmem allocator is getting replaced by memblock. To
cover the needs of the s390 kdump implementation the physical memory
list is used.
With this patch the bootmem allocator and its bitmaps are completely
removed from s390.

Signed-off-by: Philipp Hachtmann 
Signed-off-by: Martin Schwidefsky

s390/mm,tlb: optimize TLB flushing for zEC12

2014-04-03T12:31:00+00:00

The zEC12 machines introduced the local-clearing control for the IDTE
and IPTE instruction. If the control is set only the TLB of the local
CPU is cleared of entries, either all entries of a single address space
for IDTE, or the entry for a single page-table entry for IPTE.
Without the local-clearing control the TLB flush is broadcasted to all
CPUs in the configuration, which is expensive.

The reset of the bit mask of the CPUs that need flushing after a
non-local IDTE is tricky. As TLB entries for an address space remain
in the TLB even if the address space is detached a new bit field is
required to keep track of attached CPUs vs. CPUs in the need of a
flush. After a non-local flush with IDTE the bit-field of attached CPUs
is copied to the bit-field of CPUs in need of a flush. The ordering
of operations on cpu_attach_mask, attach_count and mm_cpumask(mm) is
such that an underindication in mm_cpumask(mm) is prevented but an
overindication in mm_cpumask(mm) is possible.

Signed-off-by: Martin Schwidefsky

s390/setup: get rid of MACHINE_HAS_MVCOS machine flag

2014-02-21T07:50:15+00:00

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 
Signed-off-by: Martin Schwidefsky

s390/sclp: Determine HSA size dynamically for zfcpdump

2013-11-15T13:08:40+00:00

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 
Signed-off-by: Michael Holzheu 
Signed-off-by: Martin Schwidefsky