linux.git/arch/parisc/include, branch v3.10

parisc: provide pci_mmap_page_range() for parisc

2013-06-18T18:29:08+00:00

pci_mmap_page_range() is needed for X11-server support on C8000 with ATI
FireGL card.

Signed-off-by Thomas Bogendoerfer 
Signed-off-by: Helge Deller

parisc: fix kernel BUG at arch/parisc/include/asm/mmzone.h:50 (part 2)

2013-06-18T18:20:21+00:00

Make sure that we really return -1 (instead of 0x00ff) as node id for
page frame numbers which are not physically available.

This finally fixes the kernel panic when running
cat /proc/kpageflags /proc/kpagecount.

Theoretically this patch now limits the number of physical memory ranges
to 127 instead of 254, but currently we have MAX_PHYSMEM_RANGES
hardcoded to 8 which is sufficient for all existing parisc machines.

Signed-off-by: Helge Deller

parisc: fix kernel BUG at arch/parisc/include/asm/mmzone.h:50

2013-06-01T12:28:35+00:00

With CONFIG_DISCONTIGMEM=y and multiple physical memory areas,
cat /proc/kpageflags triggers this kernel bug:

kernel BUG at arch/parisc/include/asm/mmzone.h:50!
CPU: 2 PID: 7848 Comm: cat Tainted: G      D W 3.10.0-rc3-64bit #44
 IAOQ[0]: kpageflags_read0x128/0x238
 IAOQ[1]: kpageflags_read0x12c/0x238
 RP(r2): proc_reg_read0xbc/0x130
Backtrace:
 [<00000000402ca2d4>] proc_reg_read0xbc/0x130
 [<0000000040235bcc>] vfs_read0xc4/0x1d0
 [<0000000040235f0c>] SyS_read0x94/0xf0
 [<0000000040105fc0>] syscall_exit0x0/0x14

kpageflags_read() walks through the whole memory, even if some memory
areas are physically not available. So, we should better not BUG on an
unavailable pfn in pfn_to_nid() but just return the expected value -1 or
0.

Signed-off-by: Helge Deller

parisc: fix irq stack on UP and SMP

2013-05-24T21:29:01+00:00

The logic to detect if the irq stack was already in use with
raw_spin_trylock() is wrong, because it will generate a "trylock failure
on UP" error message with CONFIG_SMP=n and CONFIG_DEBUG_SPINLOCK=y.

arch_spin_trylock() can't be used either since in the CONFIG_SMP=n case
no atomic protection is given and we are reentrant here. A mutex didn't
worked either and brings more overhead by turning off interrupts.

So, let's use the fastest path for parisc which is the ldcw instruction.

Counting how often the irq stack was used is pretty useless, so just
drop this piece of code.

Signed-off-by: Helge Deller

parisc: make interrupt and interruption stack allocation reentrant

2013-05-24T20:35:36+00:00

The get_stack_use_cr30 and get_stack_use_r30 macros allocate a stack
frame for external interrupts and interruptions requiring a stack frame.
They are currently not reentrant in that they save register context
before the stack is set or adjusted.

I have observed a number of system crashes where there was clear
evidence of stack corruption during interrupt processing, and as a
result register corruption. Some interruptions can still occur during
interruption processing, however external interrupts are disabled and
data TLB misses don't occur for absolute accesses. So, it's not entirely
clear what triggers this issue. Also, if an interruption occurs when
Q=0, it is generally not possible to recover as the shadowed registers
are not copied.

The attached patch reworks the get_stack_use_cr30 and get_stack_use_r30
macros to allocate stack before doing register saves. The new code is a
couple of instructions shorter than the old implementation. Thus, it's
an improvement even if it doesn't fully resolve the stack corruption
issue. Based on limited testing, it improves SMP system stability.

Signed-off-by: John David Anglin 
Signed-off-by: Helge Deller

parisc: show number of FPE and unaligned access handler calls in /proc/interrupts

2013-05-24T20:35:26+00:00

Show number of floating point assistant and unaligned access fixup
handler in /proc/interrupts file.

Signed-off-by: Helge Deller

parisc: implement irq stacks - part 2 (v2)

2013-05-11T19:10:15+00:00

This patch fixes few build issues which were introduced with the last
irq stack patch, e.g. the combination of stack overflow check and irq
stack.

Furthermore we now do proper locking and change the irq bh handler
to use the irq stack as well.

In /proc/interrupts one now can monitor how huge the irq stack has grown
and how often it was preferred over the kernel stack.

IRQ stacks are now enabled by default just to make sure that we not
overflow the kernel stack by accident.

Signed-off-by: Helge Deller

parisc: tlb flush counting fix for SMP and UP

2013-05-07T21:44:04+00:00

Fix up build error on UP and show correctly number of function call
(ipi) irqs.

Signed-off-by: Helge Deller

parisc: more irq statistics in /proc/interrupts

2013-05-07T20:39:22+00:00

Add framework and initial values for more fine grained statistics in
/proc/interrupts.

Signed-off-by: Helge Deller

parisc: implement irq stacks

2013-05-07T20:30:35+00:00

Default kernel stack size on parisc is 16k.  During tests we found that the
kernel stack can easily grow beyond 13k, which leaves 3k left for irq
processing.

This patch adds the possibility to activate an additional stack of 16k per CPU
which is being used during irq processing.  This implementation does not yet
uses this irq stack for the irq bh handler.

The assembler code for call_on_stack was heavily cleaned up by John
David Anglin.

CC: John David Anglin 
Signed-off-by: Helge Deller