kernel_optimize_test/arch/arm/include/asm
Nicolas Pitre 7e5a69e83b ARM: 6007/1: fix highmem with VIPT cache and DMA
The VIVT cache of a highmem page is always flushed before the page
is unmapped.  This cache flush is explicit through flush_cache_kmaps()
in flush_all_zero_pkmaps(), or through __cpuc_flush_dcache_area() in
kunmap_atomic().  There is also an implicit flush of those highmem pages
that were part of a process that just terminated making those pages free
as the whole VIVT cache has to be flushed on every task switch. Hence
unmapped highmem pages need no cache maintenance in that case.

However unmapped pages may still be cached with a VIPT cache because the
cache is tagged with physical addresses.  There is no need for a whole
cache flush during task switching for that reason, and despite the
explicit cache flushes in flush_all_zero_pkmaps() and kunmap_atomic(),
some highmem pages that were mapped in user space end up still cached
even when they become unmapped.

So, we do have to perform cache maintenance on those unmapped highmem
pages in the context of DMA when using a VIPT cache.  Unfortunately,
it is not possible to perform that cache maintenance using physical
addresses as all the L1 cache maintenance coprocessor functions accept
virtual addresses only.  Therefore we have no choice but to set up a
temporary virtual mapping for that purpose.

And of course the explicit cache flushing when unmapping a highmem page
on a system with a VIPT cache now can go, which should increase
performance.

While at it, because the code in __flush_dcache_page() has to be modified
anyway, let's also make sure the mapped highmem pages are pinned with
kmap_high_get() for the duration of the cache maintenance operation.
Because kunmap() does unmap highmem pages lazily, it was reported by
Gary King <GKing@nvidia.com> that those pages ended up being unmapped
during cache maintenance on SMP causing segmentation faults.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-04-14 11:11:27 +01:00
..
hardware Merge branch 'origin' into devel-stable 2010-03-08 20:21:04 +00:00
mach ARM: remove old RTC support 2010-02-15 21:39:12 +00:00
a.out-core.h
a.out.h headers_check fix: arm, a.out.h 2009-02-01 11:01:22 +05:30
asm-offsets.h kbuild: move asm-offsets.h to include/generated 2009-12-12 13:08:14 +01:00
assembler.h Merge branch 'for-rmk-2.6.32' of git://git.pengutronix.de/git/ukl/linux-2.6 into devel-stable 2009-08-15 16:51:48 +01:00
atomic.h ARM: 5889/1: Add atomic64 routines for ARMv6k and above. 2010-02-15 21:39:50 +00:00
auxvec.h
bitops.h ARM: boolean bit testing 2009-10-11 16:25:06 +01:00
bitsperlong.h asm-generic: introduce asm/bitsperlong.h 2009-06-11 21:02:14 +02:00
bug.h [ARM] 5211/2: fix a couple warnings from BUG() usage 2008-09-01 12:06:27 +01:00
bugs.h
byteorder.h byteorder: make swab.h include asm/swab.h like a regular header 2009-01-14 19:56:50 -08:00
cache.h ARM: 5700/1: ARM: Introduce ARM_L1_CACHE_SHIFT to define cache line size 2009-09-15 22:06:38 +01:00
cacheflush.h ARM: 5993/1: ARM: Move the outer_cache definitions into a separate file (1/4) 2010-03-25 21:13:49 +00:00
cachetype.h [ARM] Introduce new bitmask based cache type macros 2008-09-25 15:35:28 +01:00
checksum.h
clkdev.h ARM: 6001/1: removing compilation warning comming from clkdev.h 2010-03-29 17:33:32 +01:00
cpu-multi32.h
cpu-single.h
cpu.h ARM: 5872/1: ARM: include needed linux/cpu.h in asm/cpu.h 2010-01-10 13:03:52 +00:00
cputime.h
cputype.h Merge branch 'devel' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into devel 2009-09-21 16:02:30 +01:00
current.h
delay.h
device.h Driver Core: Add platform device arch data V3 2009-07-22 00:28:38 +02:00
div64.h [ARM] 5320/1: fix assembly constraints in implementation of do_div() 2008-10-23 12:53:32 +01:00
dma-mapping.h dma-mapping: arm: use generic pci_set_dma_mask and pci_set_consistent_dma_mask 2010-03-12 15:52:42 -08:00
dma.h ARM: 5870/1: arch/arm: Fix build failure for defconfigs without CONFIG_ISA_DMA_API set 2010-01-10 00:08:03 +00:00
domain.h
ecard.h
elf.h ARM: 5987/1: fix warning in kernel/elfcore.c from ARM's elf.h 2010-03-13 10:48:22 +00:00
emergency-restart.h
entry-macro-vic2.S ARM: Add common entry code for system with two VICs 2010-01-15 17:10:14 +09:00
errno.h
fb.h
fcntl.h
fiq.h
fixmap.h [ARM] fixmap support 2009-03-15 21:01:20 -04:00
flat.h flat: fix data sections alignment 2009-05-29 08:40:02 -07:00
floppy.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
fpstate.h
ftrace.h Merge branch 'devel-stable' into devel 2009-09-12 12:02:26 +01:00
futex.h Thumb-2: Implementation of the unified start-up and exceptions code 2009-07-24 12:32:54 +01:00
glue.h ARM: 5727/1: Pass IFSR register to do_PrefetchAbort() 2009-10-02 22:34:32 +01:00
gpio.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
hardirq.h
highmem.h ARM: 6007/1: fix highmem with VIPT cache and DMA 2010-04-14 11:11:27 +01:00
hw_irq.h [ARM] Fix circular include dependency with IRQ headers 2008-08-07 09:39:37 +01:00
hwcap.h [ARM] 5388/1: Add hwcap bits for VFPv3 and VFPv3D16 2009-02-12 10:59:44 +00:00
ide.h
io.h ARM: Add caller information to ioremap 2010-02-15 21:39:11 +00:00
ioctl.h
ioctls.h
ipcbuf.h
irq_regs.h
irq.h ARM: 6000/1: removing compilation warning comming from <asm/irq.h> 2010-03-29 17:33:31 +01:00
irqflags.h
Kbuild byteorder: make swab.h include asm/swab.h like a regular header 2009-01-14 19:56:50 -08:00
kdebug.h
kexec.h kexec jump: rename KEXEC_CONTROL_CODE_SIZE to KEXEC_CONTROL_PAGE_SIZE 2008-08-15 08:35:42 -07:00
kgdb.h
kmap_types.h ARM: 6007/1: fix highmem with VIPT cache and DMA 2010-04-14 11:11:27 +01:00
kprobes.h [ARM] 5206/1: remove kprobe_trap_handler() hack 2008-09-01 12:06:26 +01:00
leds.h
limits.h
linkage.h
local.h
localtimer.h [ARM] smp: allow re-use of realview localtimer TWD support 2009-05-17 19:16:41 +01:00
locks.h
mach-types.h arm: move mach-types to include/generated 2009-12-12 13:08:14 +01:00
mc146818rtc.h [ARM] Convert asm/io.h to linux/io.h 2008-09-06 12:10:45 +01:00
memory.h ARM: 5928/1: Change type of VMALLOC_END to unsigned long. 2010-02-15 21:40:33 +00:00
mman.h arm: add arch_mmap_check(), get rid of sys_arm_mremap() 2009-12-11 06:34:09 -05:00
mmu_context.h ARM: 5905/1: ARM: Global ASID allocation on SMP 2010-02-15 21:39:51 +00:00
mmu.h ARM: 5905/1: ARM: Global ASID allocation on SMP 2010-02-15 21:39:51 +00:00
mmzone.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
module.h [ARM] 5384/1: unwind: Add stack unwinding support for loadable modules 2009-02-19 11:27:19 +00:00
msgbuf.h
mtd-xip.h [ARM] move asm/xip.h's mach/hardware.h include to mach/xip.h 2008-12-14 13:22:51 +00:00
mutex.h
nwflash.h
outercache.h ARM: 5994/1: ARM: Add outer_cache_fns.sync function pointer (2/4) 2010-03-25 21:13:49 +00:00
page-nommu.h nommu: Remove the memory_start/end variables from ARM page-nommu.h 2009-07-24 12:35:01 +01:00
page.h ARM: Pass VMA to copy_user_highpage() implementations 2009-10-05 15:17:45 +01:00
param.h
parport.h
pci.h pci-dma: add linux/pci-dma.h to linux/pci.h 2010-03-12 15:52:42 -08:00
percpu.h
perf_event.h ARM: 5900/2: arm: enable support for software perf events 2010-02-12 17:25:53 +00:00
pgalloc.h ARM: implement highpte 2009-08-17 20:02:06 +01:00
pgtable-hwdef.h
pgtable-nommu.h ARM: 5988/1: pgprot_dmacoherent() for non-mmu builds 2010-03-13 10:48:22 +00:00
pgtable.h ARM: dma-mapping: switch ARMv7 DMA mappings to retain 'memory' attribute 2009-11-24 17:41:36 +00:00
pmu.h ARM: 5899/2: arm: provide a mechanism to reserve performance counters 2010-02-12 17:23:43 +00:00
poll.h
posix_types.h
proc-fns.h ARM: Kill CONFIG_CPU_32 2009-12-18 16:07:53 +00:00
processor.h Add core support for ARMv6/v7 big-endian 2009-05-30 14:00:18 +01:00
procinfo.h
ptrace.h arm: use generic ptrace_resume code 2010-03-12 15:52:38 -08:00
resource.h
scatterlist.h
sections.h
segment.h
sembuf.h
serial.h
setup.h ARM: 5880/1: arm: use generic infrastructure for early params 2010-02-15 21:39:13 +00:00
shmbuf.h
shmparam.h
sigcontext.h
siginfo.h
signal.h asm-generic: rename termios.h, signal.h and mman.h 2009-06-11 21:01:52 +02:00
sizes.h [ARM] Kirkwood: create a mapping for the Security Accelerator SRAM 2009-06-08 13:05:02 -04:00
smp_plat.h ARM: Fix ptrace accesses 2009-12-14 14:54:28 +00:00
smp_scu.h [ARM] smp: separate SCU support code from realview 2009-05-17 19:00:37 +01:00
smp_twd.h [ARM] smp: allow re-use of realview localtimer TWD support 2009-05-17 19:16:41 +01:00
smp.h cpumask: remove arch_send_call_function_ipi 2009-09-24 09:34:47 +09:30
socket.h net: Generalize socket rx gap / receive queue overflow cmsg 2009-10-12 13:26:31 -07:00
sockios.h
sparsemem.h [ARM] mm: enable sparsemem on clps7500 and RiscPC 2008-10-01 17:24:04 +01:00
spinlock_types.h locking: Convert raw_rwlock to arch_rwlock 2009-12-14 23:55:32 +01:00
spinlock.h ARM: 5897/1: spinlock: don't use deprecated barriers on ARMv7 2010-02-15 21:39:50 +00:00
stacktrace.h [ARM] 5382/1: unwind: Reorganise the stacktrace support 2009-02-12 13:21:17 +00:00
stat.h
statfs.h ARM: Use <asm-generic/statfs.h> 2008-09-04 09:46:11 +01:00
string.h [ARM] remove memzero() 2008-11-27 12:37:59 +00:00
swab.h ARM: 5772/1: Use REV and REV16 for byte swapping on ARMv6+ 2009-10-25 15:59:53 +00:00
system.h ARM: 5996/1: ARM: Change the mandatory barriers implementation (4/4) 2010-03-25 21:13:50 +00:00
tcm.h ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3 2009-09-15 22:11:05 +01:00
termbits.h
termios.h
therm.h
thread_info.h ARM: vfp ptrace: no point flushing hw context for PTRACE_GETVFPREGS 2010-02-15 21:39:53 +00:00
thread_notify.h ARM: Convert VFP/Crunch/XscaleCP thread_release() to exit_thread() 2009-12-18 14:53:41 +00:00
timex.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
tlb.h mm: Pass virtual address to [__]p{te,ud,md}_free_tlb() 2009-07-27 12:10:38 -07:00
tlbflush.h MM: Pass a PTE pointer to update_mmu_cache() rather than the PTE itself 2010-02-20 16:41:46 +00:00
topology.h
traps.h [ARM] 5381/1: unwind: Reorganise the traps.c code 2009-02-12 13:21:15 +00:00
types.h
uaccess.h Thumb-2: Implement the unified arch/arm/lib functions 2009-07-24 12:32:57 +01:00
ucontext.h
unaligned.h
unified.h Fix "W" macro in arch/arm/include/asm/unified.h 2009-09-18 23:30:11 +01:00
unistd.h Add generic sys_ipc wrapper 2010-03-12 15:52:32 -08:00
unwind.h [ARM] 5383/2: unwind: Add core support for ARM stack unwinding 2009-02-19 11:26:24 +00:00
user.h [ARM] 5387/1: Add ptrace VFP support on ARM 2009-02-12 10:59:43 +00:00
vfp.h
vfpmacros.h
vga.h [ARM] Convert asm/io.h to linux/io.h 2008-09-06 12:10:45 +01:00
xor.h