kernel_optimize_test/include/asm-m68k
Martin Schwidefsky 2f569afd9c CONFIG_HIGHPTE vs. sub-page page tables.
Background: I've implemented 1K/2K page tables for s390.  These sub-page
page tables are required to properly support the s390 virtualization
instruction with KVM.  The SIE instruction requires that the page tables
have 256 page table entries (pte) followed by 256 page status table entries
(pgste).  The pgstes are only required if the process is using the SIE
instruction.  The pgstes are updated by the hardware and by the hypervisor
for a number of reasons, one of them is dirty and reference bit tracking.
To avoid wasting memory the standard pte table allocation should return
1K/2K (31/64 bit) and 2K/4K if the process is using SIE.

Problem: Page size on s390 is 4K, page table size is 1K or 2K.  That means
the s390 version for pte_alloc_one cannot return a pointer to a struct
page.  Trouble is that with the CONFIG_HIGHPTE feature on x86 pte_alloc_one
cannot return a pointer to a pte either, since that would require more than
32 bit for the return value of pte_alloc_one (and the pte * would not be
accessible since its not kmapped).

Solution: The only solution I found to this dilemma is a new typedef: a
pgtable_t.  For s390 pgtable_t will be a (pte *) - to be introduced with a
later patch.  For everybody else it will be a (struct page *).  The
additional problem with the initialization of the ptl lock and the
NR_PAGETABLE accounting is solved with a constructor pgtable_page_ctor and
a destructor pgtable_page_dtor.  The page table allocation and free
functions need to call these two whenever a page table page is allocated or
freed.  pmd_populate will get a pgtable_t instead of a struct page pointer.
 To get the pgtable_t back from a pmd entry that has been installed with
pmd_populate a new function pmd_pgtable is added.  It replaces the pmd_page
call in free_pte_range and apply_to_pte_range.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:42 -08:00
..
a.out-core.h aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUT 2008-02-08 09:22:30 -08:00
a.out.h aout: move STACK_TOP[_MAX] to asm/processor.h 2008-02-08 09:22:29 -08:00
adb_iop.h
amigahw.h
amigaints.h
amigayle.h
amipcmcia.h
apollodma.h
apollohw.h
atafd.h
atafdreg.h
atari_joystick.h
atari_stdma.h IRQ: Use the new typedef for interrupt handler function pointers 2006-10-09 12:19:47 +01:00
atari_stram.h
atarihw.h further UTF-8 fixes and name correction 2007-05-11 19:09:46 +02:00
atariints.h further UTF-8 fixes and name correction 2007-05-11 19:09:46 +02:00
atarikb.h m68k: Atari keyboard and mouse support. 2007-05-04 17:59:05 -07:00
atomic.h atomic.h: atomic_add_unless as inline. Remove system.h atomic.h circular dependency 2007-05-08 11:15:20 -07:00
auxvec.h
bitops.h ext4: Add ext4_find_next_bit() 2008-01-28 23:58:27 -05:00
blinken.h
bootinfo.h
bug.h
bugs.h
bvme6000hw.h
byteorder.h
cache.h
cachectl.h
cacheflush.h [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
checksum.h [NET]: M68K checksum annotations and cleanups. 2006-12-02 21:23:07 -08:00
contregs.h
cputime.h
current.h
delay.h
device.h Driver core: add dev_archdata to struct device 2006-12-01 14:52:01 -08:00
div64.h [NET]: div64_64 consolidate (rev3) 2007-04-25 22:23:33 -07:00
dma-mapping.h [PATCH] m68k dma-mapping: gfp_t annotations 2007-03-14 15:27:51 -07:00
dma.h
dsp56k.h
dvma.h
elf.h Cleanup asm/{elf,page,user}.h: #ifdef __KERNEL__ is no longer needed 2008-02-07 08:42:30 -08:00
emergency-restart.h
entry.h
errno.h
fb.h fbdev: detect primary display device 2007-07-17 10:23:11 -07:00
fbio.h
fcntl.h
floppy.h cleanup floppy.h 2007-10-17 08:42:55 -07:00
fpu.h
futex.h
hardirq.h
hp300hw.h
hw_irq.h
hwtest.h
ide.h ide: add hwif->ack_intr hook 2007-10-20 00:32:32 +02:00
idprom.h
intersil.h
io.h Remove dma_cache_(wback|inv|wback_inv) functions 2007-10-17 08:42:57 -07:00
ioctl.h
ioctls.h m68k: Enable arbitary speed tty support 2007-08-22 19:52:45 -07:00
ipcbuf.h
irq_regs.h [PATCH] m68k pt_regs fixes, part 2 2006-10-08 12:32:35 -07:00
irq.h take declarations of enable_irq() et.al. to linux/interrupt.h 2007-07-22 11:44:00 -07:00
Kbuild m68k: Export cachectl.h 2007-10-13 09:41:03 -07:00
kdebug.h move die notifier handling to common code 2007-05-08 11:15:04 -07:00
kmap_types.h
linkage.h
local.h
mac_asc.h
mac_baboon.h
mac_iop.h [PATCH] m68k pt_regs fixes 2006-10-07 10:51:14 -07:00
mac_mouse.h
mac_oss.h
mac_psc.h
mac_via.h
machdep.h IRQ: Use the new typedef for interrupt handler function pointers 2006-10-09 12:19:47 +01:00
machines.h
machw.h
macintosh.h mac68k: remove dead code 2008-02-05 09:44:24 -08:00
macints.h
math-emu.h [PATCH] m68k: work around binutils tokenizer change 2007-02-11 10:51:20 -08:00
mc146818rtc.h [PATCH] rtc-cmos needs RTC_ALWAYS_BCD known 2007-03-14 15:27:49 -07:00
md.h
mman.h
mmu_context.h [PATCH] x86: PARAVIRT: add hooks to intercept mm creation and destruction 2007-05-02 19:27:14 +02:00
mmu.h
mmzone.h m68k: discontinuous memory support 2007-05-31 07:58:14 -07:00
module.h m68k: discontinuous memory support 2007-05-31 07:58:14 -07:00
motorola_pgalloc.h CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
motorola_pgtable.h m68k: kill page walker compile warning 2008-02-07 09:10:06 -08:00
movs.h
msgbuf.h
mutex.h
mvme16xhw.h
mvme147hw.h
namei.h
nubus.h
openprom.h
oplib.h [SPARC]: Kill prom_getname, unused and not implemented properly. 2006-07-21 14:17:55 -07:00
page_offset.h
page.h CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
param.h avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
parport.h
pci.h PCI: Use a weak symbol for the empty version of pcibios_add_platform_entries() 2007-07-11 16:02:07 -07:00
percpu.h
pgalloc.h m68k: discontinuous memory support 2007-05-31 07:58:14 -07:00
pgtable.h cleanup after APUS removal 2008-02-06 10:41:01 -08:00
poll.h Consolidate asm/poll.h 2007-05-11 08:29:34 -07:00
posix_types.h asm-*/posix_types.h: scrub __GLIBC__ 2008-02-08 09:22:34 -08:00
processor.h aout: move STACK_TOP[_MAX] to asm/processor.h 2008-02-08 09:22:29 -08:00
ptrace.h
q40_master.h
q40ints.h
raw_io.h m68k {in,out}_le{16,32} endianness misannotation 2007-07-26 11:11:57 -07:00
resource.h
rtc.h fix file specification in comments 2006-10-03 23:01:26 +02:00
sbus.h
scatterlist.h Add CONFIG_DEBUG_SG sg validation 2007-10-22 21:20:03 +02:00
sections.h
segment.h
semaphore-helper.h
semaphore.h kill DECLARE_MUTEX_LOCKED 2007-10-17 08:42:47 -07:00
sembuf.h
serial.h
setup.h [PATCH] cleanup asm/setup.h userspace visibility 2006-12-07 08:39:46 -08:00
shm.h
shmbuf.h
shmparam.h
sigcontext.h
siginfo.h
signal.h [PATCH] missing forward declaration of pt_regs (asm-m68k/signal.h) 2006-10-08 12:32:36 -07:00
socket.h [NET]: Introducing socket mark socket option. 2008-01-31 19:27:19 -08:00
sockios.h [NET]: Introduce SIOCGSTAMPNS ioctl to get timestamps with nanosec resolution 2007-04-25 22:24:04 -07:00
spinlock.h
stat.h
statfs.h
string.h [PATCH] m68k: cleanup string functions 2006-10-06 08:53:40 -07:00
sun3_pgalloc.h CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
sun3_pgtable.h page table handling cleanup 2007-07-16 09:05:36 -07:00
sun3-head.h [PATCH] Sun3: General updates 2006-12-09 09:41:18 -08:00
sun3ints.h [PATCH] Sun3: General updates 2006-12-09 09:41:18 -08:00
sun3mmu.h [PATCH] sun3_ioremap() prototype 2006-10-15 11:00:58 -07:00
sun3x.h
sun3xflop.h [PATCH] m68k pt_regs fixes 2006-10-07 10:51:14 -07:00
sun3xprom.h
suspend.h
system.h Add cmpxchg_local to m86k 2008-02-07 08:42:32 -08:00
termbits.h m68k: Enable arbitary speed tty support 2007-08-22 19:52:45 -07:00
termios.h m68k: Enable arbitary speed tty support 2007-08-22 19:52:45 -07:00
thread_info.h rename thread_info to stack 2007-05-09 12:30:56 -07:00
timex.h
tlb.h
tlbflush.h remove unused flush_tlb_pgtables 2007-10-19 11:53:34 -07:00
topology.h
traps.h
types.h remove strict ansi check from __u64 in asm/types.h 2007-10-17 08:42:53 -07:00
uaccess.h m68k: implement __clear_user() 2007-05-15 08:54:00 -07:00
ucontext.h
unaligned.h
unistd.h m68k: ignore restart_syscall 2007-10-13 09:41:03 -07:00
user.h Sanitize the type of struct user.u_ar0 2008-02-07 08:42:30 -08:00
virtconvert.h m68k: discontinuous memory support 2007-05-31 07:58:14 -07:00
xor.h
zorro.h