Commit graph

112 commits

Author SHA1 Message Date
Ingo Molnar
3dd392a407 Merge branch 'linus' into x86/pat2
Conflicts:
	arch/x86/mm/init_64.c
2008-10-10 19:30:08 +02:00
Suresh Siddha
ad5ca55f6b x86, cpa: srlz cpa(), global flush tlb after splitting big page and before doing cpa
Do a global flush tlb after splitting the large page and before we do the
actual change page attribute in the PTE.

With out this, we violate the TLB application note, which says
    "The TLBs may contain both ordinary and large-page translations for
     a 4-KByte range of linear addresses. This may occur if software
     modifies the paging structures so that the page size used for the
     address range changes. If the two translations differ with respect
     to page frame or attributes (e.g., permissions), processor behavior
     is undefined and may be implementation-specific."

And also serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity
mappings) using cpa_lock. So that we don't allow any other cpu, with stale
large tlb entries change the page attribute in parallel to some other cpu
splitting a large page entry along with changing the attribute.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: arjan@linux.intel.com
Cc: venkatesh.pallipadi@intel.com
Cc: jeremy@goop.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10 19:29:17 +02:00
Suresh Siddha
8311eb84bf x86, cpa: remove cpa pool code
Interrupt context no longer splits large page in cpa(). So we can do away
with cpa memory pool code.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: arjan@linux.intel.com
Cc: venkatesh.pallipadi@intel.com
Cc: jeremy@goop.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10 19:29:16 +02:00
Suresh Siddha
55121b4369 x86, cpa: no need to check alias for __set_pages_p/__set_pages_np
No alias checking needed for setting present/not-present mapping. Otherwise,
we may need to break large pages for 64-bit kernel text mappings (this adds to
complexity if we want to do this from atomic context especially, for ex:
with CONFIG_DEBUG_PAGEALLOC). Let's keep it simple!

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: arjan@linux.intel.com
Cc: venkatesh.pallipadi@intel.com
Cc: jeremy@goop.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10 19:29:15 +02:00
Ingo Molnar
e496e3d645 Merge branches 'x86/alternatives', 'x86/cleanups', 'x86/commandline', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/doc', 'x86/exports', 'x86/fpu', 'x86/gart', 'x86/idle', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/oprofile', 'x86/paravirt', 'x86/reboot', 'x86/sparse-fixes', 'x86/tsc', 'x86/urgent' and 'x86/vmalloc' into x86-v28-for-linus-phase1 2008-10-06 18:17:07 +02:00
Bruce Allan
a03352d2c1 x86: export set_memory_ro and set_memory_rw
Export set_memory_ro() and set_memory_rw() calls for use by drivers that need
to have more debug information about who might be writing to memory space.
this was initially developed for use while debugging a memory corruption
problem with e1000e.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-30 09:06:41 +02:00
Ingo Molnar
ea1c9de45e Merge branch 'x86/urgent' into x86/cleanups 2008-08-25 11:10:42 +02:00
Venki Pallipadi
01de05af94 x86: have set_memory_array_{uc,wb} coalesce memtypes, fix
Fix the start addr for free_memtype calls in the error path.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Rene Herman <rene.herman@keyaccess.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-23 17:33:12 +02:00
Rene Herman
c5e147cf5a x86: have set_memory_array_{uc,wb} coalesce memtypes.
Actually, might as well simply reconstruct the memtype list at free time
I guess. How is this for a coalescing version of the array functions?

Compiles, boots and provides me with:

  root@7ixe4:~# wc -l /debug/x86/pat_memtype_list
  53 /debug/x86/pat_memtype_list

otherwise (down from 16384+).

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22 06:07:32 +02:00
Rene Herman
9a79f4f491 x86: {reverve,free}_memtype() take a physical address
The new set_memory_array_{uc,wb}() pass virtual addresses to
{reserve,free}_memtype() it seems.

Signed-off-by: Rene Herman <rene.herman@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22 06:07:32 +02:00
Ingo Molnar
8b53b57576 Merge branch 'x86/urgent' into x86/pat
Conflicts:
	arch/x86/mm/pageattr.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22 06:06:51 +02:00
Shaohua Li
d75586ad01 x86, pageattr: introduce APIs to change pageattr of a page array
Add array interface APIs of pageattr. page based cache flush is quite
slow for a lot of pages. If pages are more than 1024 (4M), the patch
will use a wbinvd(). We have a simple test here (run a 3d game - open
arena), nearly all agp memory allocation are small (< 1M), so suppose
this will not impact runtime performance.

Signed-off-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21 13:47:45 +02:00
Ingo Molnar
cacf890694 Revert "introduce two APIs for page attribute"
This reverts commit 1ac2f7d55b.
2008-08-21 13:46:33 +02:00
venkatesh.pallipadi@intel.com
c15238df3b x86: PAT proper tracking of set_memory_uc and friends
Big thinko in pat memtype tracking code. reserve_memtype should be called
with physical address and not virtual address.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21 13:27:32 +02:00
Ingo Molnar
7393423dd9 Merge branch 'linus' into x86/cleanups 2008-08-20 11:52:15 +02:00
Nick Piggin
5843d9a4d0 x86, pat: avoid highmem cache attribute aliasing
Highmem code can leave ptes and tlb entries around for a given page even after
kunmap, and after it has been freed.

>From what I can gather, the PAT code may change the cache attributes of
arbitrary physical addresses (ie. including highmem pages), which would result
in aliases in the case that it operates on one of these lazy tlb highmem
pages.

Flushing kmaps should solve the problem.

I've also just added code for conditional flushing if we haven't got
any dangling highmem aliases -- this should help performance if we
change page attributes frequently or systems that aren't using much
highmem pages (eg. if < 4G RAM). Should be turned into 2 patches, but
just for RFC...

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 17:22:57 +02:00
Shaohua Li
1ac2f7d55b introduce two APIs for page attribute
Introduce two APIs for page attribute. flushing tlb/cache in every page
attribute is expensive. AGP gart usually will do a lot of operations to
change a page to uc, new APIs can reduce flush.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: airlied@linux.ie
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 16:30:45 +02:00
Hugh Dickins
a06de63000 x86: fix /proc/meminfo DirectMap
Do we actually want these DirectMap lines in the x86 /proc/meminfo?
I can see they're interesting to CPA developers and TLB optimizers,
but they don't fit its usual "where has all my memory gone?" usage.
If they are to stay, here are some fixes.

1. On x86_32 without PAE, they're not 2M but 4M pages: no need to
   mess with the internal enum, but show the right name to users.

2. Many machines can never show anything but 0 for DirectMap1G,
   so suppress that line unless direct_gbpages are really enabled.

3. The unit in /proc/meminfo is kB not number of pages: HugePages
   messed that up, but they're an example to regret not to follow.

4. Once we use kB, it's easy to see that 1GB has gone missing (which
   explains why CONFIG_CPA_DEBUG=y soon wraps DirectMap2M negative):
   because head_64.S's level2_ident_pgt entries were not counted.
   My fix is not ideal, but works for more and for less than 1G,
   and avoids interfering with early bootup pagetable contortions.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 15:27:55 +02:00
Arjan van de Ven
875e40b975 x86: use WARN() in arch/x86/mm/pageattr.c
Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes
part of the warning section for better reporting/collection.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-13 19:05:39 +02:00
Joerg Roedel
15ae2d76ce x86: convert pageattr.c from round_up to roundup
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-26 15:39:20 +02:00
Ingo Molnar
1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Ingo Molnar
5806b81ac1 Merge branch 'auto-ftrace-next' into tracing/for-linus
Conflicts:

	arch/x86/kernel/entry_32.S
	arch/x86/kernel/process_32.c
	arch/x86/kernel/process_64.c
	arch/x86/lib/Makefile
	include/asm-x86/irqflags.h
	kernel/Makefile
	kernel/sched.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 16:11:52 +02:00
Yinghai Lu
965194c15d x86: max_low_pfn_mapped fix, #2
tighten the boundary checks around max_low_pfn_mapped - dont overmap
nor undermap into holes.

also print out tseg for AMD cpus, for diagnostic purposes.
(this is an SMM area, and we split up any big mappings around that area)

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-13 08:19:16 +02:00
Yinghai Lu
f361a450bf x86: introduce max_low_pfn_mapped for 64-bit
when more than 4g memory is installed, don't map the big hole below 4g.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 10:24:04 +02:00
Ingo Molnar
6924d1ab8b Merge branches 'x86/numa-fixes', 'x86/apic', 'x86/apm', 'x86/bitops', 'x86/build', 'x86/cleanups', 'x86/cpa', 'x86/cpu', 'x86/defconfig', 'x86/gart', 'x86/i8259', 'x86/intel', 'x86/irqstats', 'x86/kconfig', 'x86/ldt', 'x86/mce', 'x86/memtest', 'x86/pat', 'x86/ptemask', 'x86/resumetrace', 'x86/threadinfo', 'x86/timers', 'x86/vdso' and 'x86/xen' into x86/devel 2008-07-08 09:16:56 +02:00
Thomas Gleixner
65280e613f x86: janitor CPA statistics patch
1) Remove __meminit from update_pages_count. It is used inside
split_pages()

2) Make the code depend on PROC_FS. Doing statistics for nothing is
useless and not adding useless code is nice to the Linux tiny folks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 08:12:05 +02:00
Andi Kleen
ce0c0e50f9 x86, generic: CPA add statistics about state of direct mapping v4
Add information about the mapping state of the direct mapping to
/proc/meminfo. I chose /proc/meminfo because that is where all the other
memory statistics are too and it is a generally useful metric even
outside debugging situations. A lot of split kernel pages means the
kernel will run slower.

This way we can see how many large pages are really used for it and how
many are split.

Useful for general insight into the kernel.

v2: Add hotplug locking to 64bit to plug a very obscure theoretical race.
    32bit doesn't need it because it doesn't support hotadd for lowmem.
    Fix some typos
v3: Rename dpages_cnt
    Add CONFIG ifdef for count update as requested by tglx
    Expand description
v4: Fix stupid bugs added in v3
    Move update_page_count to pageattr.c

Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 08:11:45 +02:00
Jens Axboe
15c8b6c1aa on_each_cpu(): kill unused 'retry' parameter
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:38 +02:00
Andreas Herrmann
499f8f84b8 x86: rename pat_wc_enabled to pat_enabled
BTW, what does pat_wc_enabled stand for? Does it mean
"write-combining"?

Currently it is used to globally switch on or off PAT support.
Thus I renamed it to pat_enabled.
I think this increases readability (and hope that I didn't miss
something).

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-12 10:14:27 +02:00
Pekka Paalanen
75bb88350e x86 mmiotrace: use lookup_address()
Use lookup_address() from pageattr.c instead of doing the same
manually. Also had to EXPORT_SYMBOL_GPL(lookup_address) to make this
work for modules. This also fixes "undefined symbol 'init_mm'"
compile error for x86_32.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 11:21:32 +02:00
Suresh Siddha
de33c442ed x86 PAT: fix performance drop for glx, use UC minus for ioremap(), ioremap_nocache() and pci_mmap_page_range()
Use UC_MINUS for ioremap(), ioremap_nocache() instead of strong UC.
Once all the X drivers move to ioremap_wc(), we can go back to strong
UC semantics for ioremap() and ioremap_nocache().

To avoid attribute aliasing issues, pci_mmap_page_range() will also
use UC_MINUS for default non write-combining mapping request.

Next steps:
	a) change all the video drivers using ioremap() or ioremap_nocache()
	   and adding WC MTTR using mttr_add() to ioremap_wc()

	b) for strict usage, we can go back to strong uc semantics
	   for ioremap() and ioremap_nocache() after some grace period for
	   completing step-a.

	c) user level X server needs to use the appropriate method for setting
	   up WC mapping (like using resourceX_wc sysfs file instead of
	   adding MTRR for WC and using /dev/mem or resourceX under /sys)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-30 23:15:35 +02:00
Linus Torvalds
4b7227ca32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-xen-next
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-xen-next: (52 commits)
  xen: add balloon driver
  xen: allow compilation with non-flat memory
  xen: fold xen_sysexit into xen_iret
  xen: allow set_pte_at on init_mm to be lockless
  xen: disable preemption during tlb flush
  xen pvfb: Para-virtual framebuffer, keyboard and pointer driver
  xen: Add compatibility aliases for frontend drivers
  xen: Module autoprobing support for frontend drivers
  xen blkfront: Delay wait for block devices until after the disk is added
  xen/blkfront: use bdget_disk
  xen: Make xen-blkfront write its protocol ABI to xenstore
  xen: import arch generic part of xencomm
  xen: make grant table arch portable
  xen: replace callers of alloc_vm_area()/free_vm_area() with xen_ prefixed one
  xen: make include/xen/page.h portable moving those definitions under asm dir
  xen: add resend_irq_on_evtchn() definition into events.c
  Xen: make events.c portable for ia64/xen support
  xen: move events.c to drivers/xen for IA64/Xen support
  xen: move features.c from arch/x86/xen/features.c to drivers/xen
  xen: add missing definitions in include/xen/interface/vcpu.h which ia64/xen needs
  ...
2008-04-25 12:32:10 -07:00
Jeremy Fitzhardinge
6944a9c894 x86: rename paravirt_alloc_pt etc after the pagetable structure
Rename (alloc|release)_(pt|pd) to pte/pmd to explicitly match the name
of the appropriate pagetable level structure.

[ x86.git merge work by Mark McLoughlin <markmc@redhat.com> ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:31 +02:00
Jeremy Fitzhardinge
1d262d3a49 x86: put paravirt stubs into common asm/pgalloc.h
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:30 +02:00
Ingo Molnar
a4928cffe6 "make namespacecheck" fixes
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-24 23:15:44 +02:00
Ingo Molnar
d1a4be630f x86 PAT: fix mmap() of holes
do not return a -EINVAL when mmap()-ing PCI holes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
2008-04-18 23:40:49 +02:00
Andi Kleen
c9caa02c52 x86: add set_memory_4k to pageattr.c
Add a new function to force split large pages into 4k pages.
This is needed for some followup optimizations.

I had to add a new field to cpa_data to pass down the information
that try_preserve_large_page should not run.

Right now no set_page_4k() because I didn't need it and all the
specialized users I have in mind would be more comfortable with
pure addresses. I also didn't export it because it's unlikely
external code needs it.

Signed-off-by: Andi Kleen <ak@suse.de>
Cc: andreas.herrmann3@amd.com
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:30 +02:00
venkatesh.pallipadi@intel.com
ef354af462 x86: PAT add set_memory_wc() interface
Add a set_memory_wc interface(), similar to set_memory_uc interface.
Callers has to call set_memory_uc, set_memory_wb and
set_memory_wc, set_memory_wb as pairs.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:20 +02:00
venkatesh.pallipadi@intel.com
1219333dfd x86: PAT use reserve free memtype in set_memory_uc
Use reserve_memtype and free_memtype interfaces in set_memory_uc/set_memory_wb
interfaces to avoid aliasing.
Usage model of set_memory_uc and set_memory_wb is for RAM memory and users
will first call set_memory_uc and call set_memory_wb after use to reset the
attribute.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:19 +02:00
venkatesh.pallipadi@intel.com
2e5d9c857d x86: PAT infrastructure patch
Sets up pat_init() infrastructure.

PAT MSR has following setting.
	PAT
	|PCD
	||PWT
	|||
	000 WB		_PAGE_CACHE_WB
	001 WC		_PAGE_CACHE_WC
	010 UC-		_PAGE_CACHE_UC_MINUS
	011 UC		_PAGE_CACHE_UC

We are effectively changing WT from boot time setting to WC.
UC_MINUS is used to provide backward compatibility to existing /dev/mem
users(X).

reserve_memtype and free_memtype are new interfaces for maintaining alias-free
mapping. It is currently implemented in a simple way with a linked list and
not optimized. reserve and free tracks the effective memory type, as a result
of PAT and MTRR setting rather than what is actually requested in PAT.

pat_init piggy backs on mtrr_init as the rules for setting both pat and mtrr
are same.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:19 +02:00
Thomas Gleixner
ee7ae7a198 x86: add debug info to DEBUG_PAGEALLOC
Add debug information for DEBUG_PAGEALLOC to get some statistics about
the pool usage and split status.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 17:40:45 +02:00
Suresh Siddha
d546b67a94 x86: fix performance drop for glx
fix the 3D performance drop reported at:

   http://bugzilla.kernel.org/show_bug.cgi?id=10328

fb drivers are using ioremap()/ioremap_nocache(), followed by mtrr_add with
WC attribute. Recent changes in page attribute code made both
ioremap()/ioremap_nocache() mappings as UC (instead of previous UC-). This
breaks the graphics performance, as the effective memory type is UC instead
of expected WC.

The correct way to fix this is to add ioremap_wc() (which uses UC- in the
absence of PAT kernel support and WC with PAT) and change all the
fb drivers to use this new ioremap_wc() API.

We can take this correct and longer route for post 2.6.25. For now,
revert back to the UC- behavior for ioremap/ioremap_nocache.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-26 22:23:41 +01:00
Rafael J. Wysocki
9b5cf48b06 x86: revert "x86: CPA: avoid split of alias mappings"
Revert:

  commit 8be8f54bae
  Author: Thomas Gleixner <tglx@linutronix.de>
  Date:   Sat Feb 23 20:43:21 2008 +0100

      x86: CPA: avoid split of alias mappings

because it clearly mishandles the case when __change_page_attr(), called
from __change_page_attr_set_clr(), changes cpa->processed to 1 and
cpa_process_alias(cpa) is executed right after that.

This crashes my x86-64 test box early in the boot process
(ref. http://bugzilla.kernel.org/show_bug.cgi?id=10140#c4).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-03 14:18:27 +01:00
Thomas Gleixner
8be8f54bae x86: CPA: avoid split of alias mappings
avoid over-eager large page splitup.

When the target area needs to be split or is split already (ioremap)
then the current code enforces the split of large mappings in the alias
regions even if we could avoid it.

Use a separate variable processed in the cpa_data structure to carry
the number of pages which have been processed instead of reusing the
numpages variable. This keeps numpages intact and gives the alias code
a chance to keep large mappings intact.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-29 18:55:42 +01:00
Ingo Molnar
92cb54a37a x86: make DEBUG_PAGEALLOC and CPA more robust
Use PF_MEMALLOC to prevent recursive calls in the DBEUG_PAGEALLOC
case. This makes the code simpler and more robust against allocation
failures.

This fixes the following fallback to non-mmconfig:

   http://lkml.org/lkml/2008/2/20/551
   http://bugzilla.kernel.org/show_bug.cgi?id=10083

Also, for DEBUG_PAGEALLOC=n reduce the pool size to one page.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-26 12:55:50 +01:00
Rafael J. Wysocki
8a235efad5 Hibernation: Handle DEBUG_PAGEALLOC on x86
Make hibernation work with CONFIG_DEBUG_PAGEALLOC set on x86, by
checking if the pages to be copied are marked as present in the
kernel mapping and temporarily marking them as present if that's not
the case.  No functional modifications are introduced if
CONFIG_DEBUG_PAGEALLOC is unset.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-02-21 02:15:28 -05:00
Andi Kleen
8e31c2ac11 x86: CPA: remove BUG_ON for LRU/Compound pages
New implementation does not use lru for anything so there is no need
to reject pages that are in the LRU. Similar for compound pages (which
were checked because they also use page->lru)

[ tglx@linutronix.de: removed unused variable ]

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-19 16:18:29 +01:00
Thomas Gleixner
f34b439f34 x86: CPA: avoid double checking of alias ranges
When the CPA code is called with an virtual address in the range of
the direct mapping or the high alias then we do not need to run
through the alias check for this range.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-18 20:54:14 +01:00
Thomas Gleixner
af96e4438a x86: CPA no alias checking for _NX
NX settings are not required to be consistent across alias mappings.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-18 20:54:14 +01:00
Thomas Gleixner
c31c7d4844 x86: CPA, fix alias checks
c_p_a() did not discover all aliases correctly. (such as when called
on vmalloc()-ed areas or ioremap()-ed areas)

Push the alias checks to the lower, physical level and consistently
discover all aliases that might exist: the low direct mappings and
the high linear kernel-text mappings (on 64-bit).

Thanks to Andi Kleen for pointing out that this was buggy.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-18 20:54:14 +01:00