1
Commit Graph

2141 Commits

Author SHA1 Message Date
Avi Kivity
a988b910ef KVM: Add API for determining the number of supported memory slots
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:23 +03:00
Avi Kivity
f725230af9 KVM: Add API to retrieve the number of supported vcpus per vm
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:23 +03:00
Harvey Harrison
7a95727567 KVM: x86 emulator: make register_address_increment and JMP_REL static inlines
Change jmp_rel() to a function as well.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:23 +03:00
Harvey Harrison
e4706772ea KVM: x86 emulator: make register_address, address_mask static inlines
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:22 +03:00
Harvey Harrison
ddcb2885e2 KVM: x86 emulator: add ad_mask static inline
Replaces open-coded mask calculation in macros.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:22 +03:00
Glauber de Oliveira Costa
790c73f628 x86: KVM guest: paravirtualized clocksource
This is the guest part of kvm clock implementation
It does not do tsc-only timing, as tsc can have deltas
between cpus, and it did not seem worthy to me to keep
adjusting them.

We do use it, however, for fine-grained adjustment.

Other than that, time comes from the host.

[randy dunlap: add missing include]
[randy dunlap: disallow on Voyager or Visual WS]

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:22 +03:00
Glauber de Oliveira Costa
18068523d3 KVM: paravirtualized clocksource: host part
This is the host part of kvm clocksource implementation. As it does
not include clockevents, it is a fairly simple implementation. We
only have to register a per-vcpu area, and start writing to it periodically.

The area is binary compatible with xen, as we use the same shadow_info
structure.

[marcelo: fix bad_page on MSR_KVM_SYSTEM_TIME]
[avi: save full value of the msr, even if enable bit is clear]
[avi: clear previous value of time_page]

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:22 +03:00
Joerg Roedel
24e09cbf48 KVM: SVM: enable LBR virtualization
This patch implements the Last Branch Record Virtualization (LBRV) feature of
the AMD Barcelona and Phenom processors into the kvm-amd module. It will only
be enabled if the guest enables last branch recording in the DEBUG_CTL MSR. So
there is no increased world switch overhead when the guest doesn't use these
MSRs.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Markus Rechberger <markus.rechberger@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:21 +03:00
Joerg Roedel
f65c229c3e KVM: SVM: allocate the MSR permission map per VCPU
This patch changes the kvm-amd module to allocate the SVM MSR permission map
per VCPU instead of a global map for all VCPUs. With this we have more
flexibility allowing specific guests to access virtualized MSRs. This is
required for LBR virtualization.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Markus Rechberger <markus.rechberger@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:21 +03:00
Joerg Roedel
e6101a96c9 KVM: SVM: let init_vmcb() take struct vcpu_svm as parameter
Change the parameter of the init_vmcb() function in the kvm-amd module from
struct vmcb to struct vcpu_svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Markus Rechberger <markus.rechberger@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:21 +03:00
Ryan Harper
2e11384c2c KVM: VMX: fix typo in VMX header define
Looking at Intel Volume 3b, page 148, table 20-11 and noticed
that the field name is 'Deliver' not 'Deliever'.  Attached patch changes
the define name and its user in vmx.c

Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:21 +03:00
Joerg Roedel
709ddebf81 KVM: SVM: add support for Nested Paging
This patch contains the SVM architecture dependent changes for KVM to enable
support for the Nested Paging feature of AMD Barcelona and Phenom processors.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:21 +03:00
Joerg Roedel
fb72d1674d KVM: MMU: add TDP support to the KVM MMU
This patch contains the changes to the KVM MMU necessary for support of the
Nested Paging feature in AMD Barcelona and Phenom Processors.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:20 +03:00
Joerg Roedel
cc4b6871e7 KVM: export the load_pdptrs() function to modules
The load_pdptrs() function is required in the SVM module for NPT support.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:20 +03:00
Joerg Roedel
4d9976bbdc KVM: MMU: make the __nonpaging_map function generic
The mapping function for the nonpaging case in the softmmu does basically the
same as required for Nested Paging. Make this function generic so it can be
used for both.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:20 +03:00
Joerg Roedel
1855267210 KVM: export information about NPT to generic x86 code
The generic x86 code has to know if the specific implementation uses Nested
Paging. In the generic code Nested Paging is called Two Dimensional Paging
(TDP) to avoid confusion with (future) TDP implementations of other vendors.
This patch exports the availability of TDP to the generic x86 code.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:19 +03:00
Joerg Roedel
6c7dac72d5 KVM: SVM: add module parameter to disable Nested Paging
To disable the use of the Nested Paging feature even if it is available in
hardware this patch adds a module parameter. Nested Paging can be disabled by
passing npt=0 to the kvm_amd module.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:19 +03:00
Joerg Roedel
e3da3acdb3 KVM: SVM: add detection of Nested Paging feature
Let SVM detect if the Nested Paging feature is available on the hardware.
Disable it to keep this patch series bisectable.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:19 +03:00
Joerg Roedel
33bd6a0b3e KVM: SVM: move feature detection to hardware setup code
By moving the SVM feature detection from the each_cpu code to the hardware
setup code it runs only once. As an additional advance the feature check is now
available earlier in the module setup process.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:19 +03:00
Joerg Roedel
9457a712a2 KVM: allow access to EFER in 32bit KVM
This patch makes the EFER register accessible on a 32bit KVM host. This is
necessary to boot 32 bit PAE guests under SVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:19 +03:00
Joerg Roedel
9f62e19a11 KVM: VMX: unifdef the EFER specific code
To allow access to the EFER register in 32bit KVM the EFER specific code has to
be exported to the x86 generic code. This patch does this in a backwards
compatible manner.

[avi: add check for EFER-less hosts]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:18 +03:00
Joerg Roedel
50a37eb4e0 KVM: align valid EFER bits with the features of the host system
This patch aligns the bits the guest can set in the EFER register with the
features in the host processor. Currently it lets EFER.NX disabled if the
processor does not support it and enables EFER.LME and EFER.LMA only for KVM on
64 bit hosts.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:18 +03:00
Joerg Roedel
f2b4b7ddf6 KVM: make EFER_RESERVED_BITS configurable for architecture code
This patch give the SVM and VMX implementations the ability to add some bits
the guest can set in its EFER register.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:18 +03:00
Sheng Yang
2384d2b326 KVM: VMX: Enable Virtual Processor Identification (VPID)
To allow TLB entries to be retained across VM entry and VM exit, the VMM
can now identify distinct address spaces through a new virtual-processor ID
(VPID) field of the VMCS.

[avi: drop vpid_sync_all()]
[avi: add "cc" to asm constraints]

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:17 +03:00
Avi Kivity
d196e34336 KVM: MMU: Decouple mmio from shadow page tables
Currently an mmio guest pte is encoded in the shadow pagetable as a
not-present trapping pte, with the SHADOW_IO_MARK bit set.  However
nothing is ever done with this information, so maintaining it is a
useless complication.

This patch moves the check for mmio to before shadow ptes are instantiated,
so the shadow code is never invoked for ptes that reference mmio.  The code
is simpler, and with future work, can be made to handle mmio concurrently.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:17 +03:00
Avi Kivity
1d6ad2073e KVM: x86 emulator: group decoding for group 1 instructions
Opcodes 0x80-0x83

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:16 +03:00
Avi Kivity
d95058a1a7 KVM: x86 emulator: add group 7 decoding
This adds group decoding for opcode 0x0f 0x01 (group 7).

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:15 +03:00
Avi Kivity
fd60754e4f KVM: x86 emulator: Group decoding for groups 4 and 5
Add group decoding support for opcode 0xfe (group 4) and 0xff (group 5).

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:15 +03:00
Avi Kivity
7d858a19ef KVM: x86 emulator: Group decoding for group 3
This adds group decoding support for opcodes 0xf6, 0xf7 (group 3).

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:14 +03:00
Avi Kivity
43bb19cd33 KVM: x86 emulator: group decoding for group 1A
This adds group decode support for opcode 0x8f.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:14 +03:00
Avi Kivity
e09d082c03 KVM: x86 emulator: add support for group decoding
Certain x86 instructions use bits 3:5 of the byte following the opcode as an
opcode extension, with the decode sometimes depending on bits 6:7 as well.
Add support for this in the main decoding table rather than an ad-hock
adaptation per opcode.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:14 +03:00
Dong, Eddie
1ae0a13def KVM: MMU: Simplify hash table indexing
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:14 +03:00
Dong, Eddie
489f1d6526 KVM: MMU: Update shadow ptes on partial guest pte writes
A guest partial guest pte write will leave shadow_trap_nonpresent_pte
in spte, which generates a vmexit at the next guest access through that pte.

This patch improves this by reading the full guest pte in advance and thus
being able to update the spte and eliminate the vmexit.

This helps pae guests which use two 32-bit writes to set a single 64-bit pte.

[truncation fix by Eric]

Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:13 +03:00
Linus Torvalds
c3bf9bc243 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-bootmem-v3
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-bootmem-v3:
  x86_64/mm: check and print vmemmap allocation continuous
  x86_64: fix setup_node_bootmem to support big mem excluding with memmap
  x86_64: make reserve_bootmem_generic() use new reserve_bootmem()
  mm: allow reserve_bootmem() cross nodes
  mm: offset align in alloc_bootmem()
  mm: fix alloc_bootmem_core to use fast searching for all nodes
  mm: make mem_map allocation continuous
2008-04-26 14:04:32 -07:00
Yinghai Lu
c2b91e2eec x86_64/mm: check and print vmemmap allocation continuous
On big systems with lots of memory, don't print out too much during
bootup, and make it easy to find if it is continuous.

on 256G 8 sockets system will get
 [ffffe20000000000-ffffe20002bfffff] PMD -> [ffff810001400000-ffff810003ffffff] on node 0
[ffffe2001c700000-ffffe2001c7fffff] potential offnode page_structs
 [ffffe20002c00000-ffffe2001c7fffff] PMD -> [ffff81000c000000-ffff8100255fffff] on node 0
[ffffe20038700000-ffffe200387fffff] potential offnode page_structs
 [ffffe2001c800000-ffffe200387fffff] PMD -> [ffff810820200000-ffff81083c1fffff] on node 1
 [ffffe20040000000-ffffe2007fffffff] PUD ->ffff811027a00000 on node 2
 [ffffe20038800000-ffffe2003fffffff] PMD -> [ffff811020200000-ffff8110279fffff] on node 2
[ffffe20054700000-ffffe200547fffff] potential offnode page_structs
 [ffffe20040000000-ffffe200547fffff] PMD -> [ffff811027c00000-ffff81103c3fffff] on node 2
[ffffe20070700000-ffffe200707fffff] potential offnode page_structs
 [ffffe20054800000-ffffe200707fffff] PMD -> [ffff811820200000-ffff81183c1fffff] on node 3
 [ffffe20080000000-ffffe200bfffffff] PUD ->ffff81202fa00000 on node 4
 [ffffe20070800000-ffffe2007fffffff] PMD -> [ffff812020200000-ffff81202f9fffff] on node 4
[ffffe2008c700000-ffffe2008c7fffff] potential offnode page_structs
 [ffffe20080000000-ffffe2008c7fffff] PMD -> [ffff81202fc00000-ffff81203c3fffff] on node 4
[ffffe200a8700000-ffffe200a87fffff] potential offnode page_structs
 [ffffe2008c800000-ffffe200a87fffff] PMD -> [ffff812820200000-ffff81283c1fffff] on node 5
 [ffffe200c0000000-ffffe200ffffffff] PUD ->ffff813037a00000 on node 6
 [ffffe200a8800000-ffffe200bfffffff] PMD -> [ffff813020200000-ffff8130379fffff] on node 6
[ffffe200c4700000-ffffe200c47fffff] potential offnode page_structs
 [ffffe200c0000000-ffffe200c47fffff] PMD -> [ffff813037c00000-ffff81303c3fffff] on node 6
 [ffffe200c4800000-ffffe200e07fffff] PMD -> [ffff813820200000-ffff81383c1fffff] on node 7

instead of a very long print out...

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-26 22:51:09 +02:00
Yinghai Lu
1a27fc0a42 x86_64: fix setup_node_bootmem to support big mem excluding with memmap
typical case: four sockets system, every node has 4g ram, and we are using:

	memmap=10g$4g

to mask out memory on node1 and node2

when numa is enabled, early_node_mem is used to get node_data and node_bootmap.

if it can not get memory from the same node with find_e820_area(), it will
use alloc_bootmem to get buff from previous nodes.

so check it and print out some info about it.

need to move early_res_to_bootmem into every setup_node_bootmem.
and it takes range that node has. otherwise alloc_bootmem could return addr
that reserved early.

depends on "mm: make reserve_bootmem can crossed the nodes".

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 22:51:08 +02:00
Yinghai Lu
8b3cd09ed2 x86_64: make reserve_bootmem_generic() use new reserve_bootmem()
"mm: make reserve_bootmem can crossed the nodes" provides new
reserve_bootmem(), let reserve_bootmem_generic() use that.

reserve_bootmem_generic() is used to reserve initramdisk, so this way
we can make sure even when bootloader or kexec load ranges cross the
node memory boundaries, reserve_bootmem still works.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 22:51:08 +02:00
Linus Torvalds
9b79ed952b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-generic-bitops-v3
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-generic-bitops-v3:
  x86, bitops: select the generic bitmap search functions
  x86: include/asm-x86/pgalloc.h/bitops.h: checkpatch cleanups - formatting only
  x86: finalize bitops unification
  x86, UML: remove x86-specific implementations of find_first_bit
  x86: optimize find_first_bit for small bitmaps
  x86: switch 64-bit to generic find_first_bit
  x86: generic versions of find_first_(zero_)bit, convert i386
  bitops: use __fls for fls64 on 64-bit archs
  generic: implement __fls on all 64-bit archs
  generic: introduce a generic __fls implementation
  x86: merge the simple bitops and move them to bitops.h
  x86, generic: optimize find_next_(zero_)bit for small constant-size bitmaps
  x86, uml: fix uml with generic find_next_bit for x86
  x86: change x86 to use generic find_next_bit
  uml: Kconfig cleanup
  uml: fix build error
2008-04-26 13:46:11 -07:00
Linus Torvalds
539a5fe226 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-bootparam
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-bootparam:
  x86, boot: Document for linked list of struct setup_data
  x86, boot: export linked list of struct setup_data via debugfs
  x86, boot: add linked list of struct setup_data
  x86, boot: add free_early to early reservation machanism
2008-04-26 13:29:41 -07:00
Huang, Ying
c14b2adf19 x86, boot: export linked list of struct setup_data via debugfs
Export linked list of struct setup_data via debugfs.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-26 21:34:42 +02:00
Huang, Ying
8b664aa66e x86, boot: add linked list of struct setup_data
This patch adds a field of 64-bit physical pointer to NULL terminated
single linked list of struct setup_data to real-mode kernel
header. This is used as a more extensible boot parameters passing
mechanism.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-26 21:34:42 +02:00
Huang, Ying
50eae2a7c9 x86, boot: add free_early to early reservation machanism
Add free_early to early reservation mechanism - this way early bootup
failure paths can stop wasting memory.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-26 21:34:42 +02:00
Venki Pallipadi
0124cecfc8 x86, PAT: disable /dev/mem mmap RAM with PAT
disable /dev/mem mmap of RAM with PAT. It makes things safer and
eliminates aliasing. A future improvement would be to avoid the
range_is_allowed duplication.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 21:28:29 +02:00
Alexander van Heukelum
19870def58 x86, bitops: select the generic bitmap search functions
Introduce GENERIC_FIND_FIRST_BIT and GENERIC_FIND_NEXT_BIT in
lib/Kconfig, defaulting to off. An arch that wants to use the
generic implementation now only has to use a select statement
to include them.

I added an always-y option (X86_CPU) to arch/x86/Kconfig.cpu
and used that to select the generic search functions. This
way ARCH=um SUBARCH=i386 automatically picks up the change
too, and arch/um/Kconfig.i386 can therefore be simplified a
bit. ARCH=um SUBARCH=x86_64 does things differently, but
still compiles fine. It seems that a "def_bool y" always
wins over a "def_bool n"?

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:17 +02:00
Alexander van Heukelum
5245698f66 x86, UML: remove x86-specific implementations of find_first_bit
x86 has been switched to the generic versions of find_first_bit
and find_first_zero_bit, but the original versions were retained.
This patch just removes the now unused x86-specific versions.

also update UML.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:17 +02:00
Alexander van Heukelum
2aba6925fd x86: switch 64-bit to generic find_first_bit
Switch x86_64 to generic find_first_bit. The x86_64-specific
implementation is not removed.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Alexander van Heukelum
77b9bd9c49 x86: generic versions of find_first_(zero_)bit, convert i386
Generic versions of __find_first_bit and __find_first_zero_bit
are introduced as simplified versions of __find_next_bit and
__find_next_zero_bit. Their compilation and use are guarded by
a new config variable GENERIC_FIND_FIRST_BIT.

The generic versions of find_first_bit and find_first_zero_bit
are implemented in terms of the newly introduced __find_first_bit
and __find_first_zero_bit.

This patch does not remove the i386-specific implementation,
but it does switch i386 to use the generic functions by setting
GENERIC_FIND_FIRST_BIT=y for X86_32.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Alexander van Heukelum
12d9c8420b x86: merge the simple bitops and move them to bitops.h
Some of those can be written in such a way that the same
inline assembly can be used to generate both 32 bit and
64 bit code.

For ffs and fls, x86_64 unconditionally used the cmov
instruction and i386 unconditionally used a conditional
branch over a mov instruction. In the current patch I
chose to select the version based on the availability
of the cmov instruction instead. A small detail here is
that x86_64 did not previously set CONFIG_X86_CMOV=y.

Improved comments for ffs, ffz, fls and variations.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Alexander van Heukelum
6fd92b63d0 x86: change x86 to use generic find_next_bit
The versions with inline assembly are in fact slower on the machines I
tested them on (in userspace) (Athlon XP 2800+, p4-like Xeon 2.8GHz, AMD
Opteron 270). The i386-version needed a fix similar to 06024f21 to avoid
crashing the benchmark.

Benchmark using: gcc -fomit-frame-pointer -Os. For each bitmap size
1...512, for each possible bitmap with one bit set, for each possible
offset: find the position of the first bit starting at offset. If you
follow ;). Times include setup of the bitmap and checking of the
results.

		Athlon		Xeon		Opteron 32/64bit
x86-specific:	0m3.692s	0m2.820s	0m3.196s / 0m2.480s
generic:	0m2.622s	0m1.662s	0m2.100s / 0m1.572s

If the bitmap size is not a multiple of BITS_PER_LONG, and no set
(cleared) bit is found, find_next_bit (find_next_zero_bit) returns a
value outside of the range [0, size]. The generic version always returns
exactly size. The generic version also uses unsigned long everywhere,
while the x86 versions use a mishmash of int, unsigned (int), long and
unsigned long.

Using the generic version does give a slightly bigger kernel, though.

defconfig:	   text    data     bss     dec     hex filename
x86-specific:	4738555  481232  626688 5846475  5935cb vmlinux (32 bit)
generic:	4738621  481232  626688 5846541  59360d vmlinux (32 bit)
x86-specific:	5392395  846568  724424 6963387  6a40bb vmlinux (64 bit)
generic:	5392458  846568  724424 6963450  6a40fa vmlinux (64 bit)

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Linus Torvalds
4a27214d7b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-fixes
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-fixes:
  x86 PAT: decouple from nonpromisc devmem
  x86 PAT: tone down debugging messages
2008-04-26 09:50:58 -07:00