Timers that fire between guest hlt and vcpu_block's add_wait_queue() are
ignored, possibly resulting in hangs.
Also make sure that atomic_inc and waitqueue_active tests happen in the
specified order, otherwise the following race is open:
CPU0 CPU1
if (waitqueue_active(wq))
add_wait_queue()
if (!atomic_read(pit_timer->pending))
schedule()
atomic_inc(pit_timer->pending)
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This interface allows user a space application to read the trace of kvm
related events through relayfs.
Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Trace markers allow userspace to trace execution of a virtual machine
in order to monitor its performance.
Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch introduces a gfn_to_pfn() function and corresponding functions like
kvm_release_pfn_dirty(). Using these new functions, we can modify the x86
MMU to no longer assume that it can always get a struct page for any given gfn.
We don't want to eliminate gfn_to_page() entirely because a number of places
assume they can do gfn_to_page() and then kmap() the results. When we support
IO memory, gfn_to_page() will fail for IO pages although gfn_to_pfn() will
succeed.
This does not implement support for avoiding reference counting for reserved
RAM or for IO memory. However, it should make those things pretty straight
forward.
Since we're only introducing new common symbols, I don't think it will break
the non-x86 architectures but I haven't tested those. I've tested Intel,
AMD, NPT, and hugetlbfs with Windows and Linux guests.
[avi: fix overflow when shifting left pfns by adding casts]
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
the main purpose of adding this functions is the abilaty to release the
spinlock that protect the kvm list while still be able to do operations
on a specific kvm in a safe way.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch introduces interpretation of some diagnose instruction intercepts.
Diagnose is our classic architected way of doing a hypercall. This patch
features the following diagnose codes:
- vm storage size, that tells the guest about its memory layout
- time slice end, which is used by the guest to indicate that it waits
for a lock and thus cannot use up its time slice in a useful way
- ipl functions, which a guest can use to reset and reboot itself
In order to implement ipl functions, we also introduce an exit reason that
causes userspace to perform various resets on the virtual machine. All resets
are described in the principles of operation book, except KVM_S390_RESET_IPL
which causes a reboot of the machine.
Acked-by: Martin Schwidefsky <martin.schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch contains the s390 interrupt subsystem (similar to in kernel apic)
including timer interrupts (similar to in-kernel-pit) and enabled wait
(similar to in kernel hlt).
In order to achieve that, this patch also introduces intercept handling
for instruction intercepts, and it implements load control instructions.
This patch introduces an ioctl KVM_S390_INTERRUPT which is valid for both
the vm file descriptors and the vcpu file descriptors. In case this ioctl is
issued against a vm file descriptor, the interrupt is considered floating.
Floating interrupts may be delivered to any virtual cpu in the configuration.
The following interrupts are supported:
SIGP STOP - interprocessor signal that stops a remote cpu
SIGP SET PREFIX - interprocessor signal that sets the prefix register of a
(stopped) remote cpu
INT EMERGENCY - interprocessor interrupt, usually used to signal need_reshed
and for smp_call_function() in the guest.
PROGRAM INT - exception during program execution such as page fault, illegal
instruction and friends
RESTART - interprocessor signal that starts a stopped cpu
INT VIRTIO - floating interrupt for virtio signalisation
INT SERVICE - floating interrupt for signalisations from the system
service processor
struct kvm_s390_interrupt, which is submitted as ioctl parameter when injecting
an interrupt, also carrys parameter data for interrupts along with the interrupt
type. Interrupts on s390 usually have a state that represents the current
operation, or identifies which device has caused the interruption on s390.
kvm_s390_handle_wait() does handle waitpsw in two flavors: in case of a
disabled wait (that is, disabled for interrupts), we exit to userspace. In case
of an enabled wait we set up a timer that equals the cpu clock comparator value
and sleep on a wait queue.
[christian: change virtio interrupt to 0x2603]
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This path introduces handling of sie intercepts in three flavors: Intercepts
are either handled completely in-kernel by kvm_handle_sie_intercept(),
or passed to userspace with corresponding data in struct kvm_run in case
kvm_handle_sie_intercept() returns -ENOTSUPP.
In case of partial execution in kernel with the need of userspace support,
kvm_handle_sie_intercept() may choose to set up struct kvm_run and return
-EREMOTE.
The trivial intercept reasons are handled in this patch:
handle_noop() just does nothing for intercepts that don't require our support
at all
handle_stop() is called when a cpu enters stopped state, and it drops out to
userland after updating our vcpu state
handle_validity() faults in the cpu lowcore if needed, or passes the request
to userland
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch contains the port of Qumranet's kvm kernel module to IBM zSeries
(aka s390x, mainframe) architecture. It uses the mainframe's virtualization
instruction SIE to run virtual machines with up to 64 virtual CPUs each.
This port is only usable on 64bit host kernels, and can only run 64bit guest
kernels. However, running 31bit applications in guest userspace is possible.
The following source files are introduced by this patch
arch/s390/kvm/kvm-s390.c similar to arch/x86/kvm/x86.c, this implements all
arch callbacks for kvm. __vcpu_run calls back into
sie64a to enter the guest machine context
arch/s390/kvm/sie64a.S assembler function sie64a, which enters guest
context via SIE, and switches world before and after that
include/asm-s390/kvm_host.h contains all vital data structures needed to run
virtual machines on the mainframe
include/asm-s390/kvm.h defines kvm_regs and friends for user access to
guest register content
arch/s390/kvm/gaccess.h functions similar to uaccess to access guest memory
arch/s390/kvm/kvm-s390.h header file for kvm-s390 internals, extended by
later patches
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
The SIE instruction on s390 uses the 2nd half of the page table page to
virtualize the storage keys of a guest. This patch offers the s390_enable_sie
function, which reorganizes the page tables of a single-threaded process to
reserve space in the page table:
s390_enable_sie makes sure that the process is single threaded and then uses
dup_mm to create a new mm with reorganized page tables. The old mm is freed
and the process has now a page status extended field after every page table.
Code that wants to exploit pgstes should SELECT CONFIG_PGSTE.
This patch has a small common code hit, namely making dup_mm non-static.
Edit (Carsten): I've modified Martin's patch, following Jeremy Fitzhardinge's
review feedback. Now we do have the prototype for dup_mm in
include/linux/sched.h. Following Martin's suggestion, s390_enable_sie() does now
call task_lock() to prevent race against ptrace modification of mm_users.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
include/linux/kvm.h defines struct kvm_dirty_log to
[...]
union {
void __user *dirty_bitmap; /* one bit per page */
__u64 padding;
};
__user requires compiler.h to compile. Currently, this works on x86
only coincidentally due to other include files. This patch makes
kvm.h compile in all cases.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Hypercall based pte updates are faster than faults, and also allow use
of the lazy MMU mode to batch operations.
Don't report the feature if two dimensional paging is enabled.
[avi:
- one mmu_op hypercall instead of one per op
- allow 64-bit gpa on hypercall
- don't pass host errors (-ENOMEM) to guest]
[akpm: warning fix on i386]
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
The patch moves the PIT model from userspace to kernel, and increases
the timer accuracy greatly.
[marcelo: make last_injected_time per-guest]
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
In the current inject_page_fault path KVM only checks if there is another PF
pending and injects a DF then. But it has to check for a pending DF too to
detect a shutdown condition in the VCPU. If this is not detected the VCPU goes
to a PF -> DF -> PF loop when it should triple fault. This patch detects this
condition and handles it with an KVM_SHUTDOWN exit to userspace.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Create large pages mappings if the guest PTE's are marked as such and
the underlying memory is hugetlbfs backed. If the largepage contains
write-protected pages, a large pte is not used.
Gives a consistent 2% improvement for data copies on ram mounted
filesystem, without NPT/EPT.
Anthony measures a 4% improvement on 4-way kernbench, with NPT.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Mark zapped root pagetables as invalid and ignore such pages during lookup.
This is a problem with the cr3-target feature, where a zapped root table fools
the faulting code into creating a read-only mapping. The result is a lockup
if the instruction can't be emulated.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
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>
This allows kvm_host.h to be #included even when struct preempt_notifier is
undefined. This is needed to build ppc asm-offsets.h.
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
* '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
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>
* '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
* Export ide_dma_exec_cmd() and __ide_dma_test_irq().
* Constify struct ide_dma_ops.
* Always set hwif->dma_ops to &sff_dma_ops in ide_setup_dma()
(it is later overriden by ide_init_port() if needed) and drop
'const struct ide_port_info *d' argument.
While at it:
* Rename __ide_dma_test_irq() to ide_dma_test_irq().
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add struct ide_dma_ops and convert core code + drivers to use it.
While at it:
* Drop "ide_" prefix from ->ide_dma_end and ->ide_dma_test_irq methods.
* Drop "ide_" "infixes" from DMA methods.
* au1xxx-ide.c:
- use auide_dma_{test_irq,end}() directly in auide_dma_timeout()
* pdc202xx_old.c:
- drop "old_" "infixes" from DMA methods
* siimage.c:
- add siimage_dma_test_irq() helper
- print SATA warning in siimage_init_one()
* Remove no longer needed ->init_hwif implementations.
v2:
* Changes based on review from Sergei:
- s/siimage_ide_dma_test_irq/siimage_dma_test_irq/
- s/drive->hwif/hwif/ in idefloppy_pc_intr().
- fix patch description w.r.t. au1xxx-ide changes
- fix au1xxx-ide build
- fix naming for cmd64*_dma_ops
- drop "ide_" and "old_" infixes
- s/hpt3xxx_dma_ops/hpt37x_dma_ops/
- s/hpt370x_dma_ops/hpt370_dma_ops/
- use correct DMA ops for HPT302/N, HPT371/N and HPT374
- s/it821x_smart_dma_ops/it821x_pass_through_dma_ops/
v3:
* Two bugs slipped in v2 (noticed by Sergei):
- use correct DMA ops for HPT374 (for real this time)
- handle HPT370/HPT370A properly
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add IDE_HFLAG_SERIALIZE_DMA host flag to serialize ports
if DMA is available and handle it in ide_init_port().
* Convert sl82c105 host driver to use this new flag.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Make ide_hwif_setup_dma() return an error value.
* Pass 'const struct ide_port_info *d' instead of 'unsigned long dmabase'
to ->init_dma method and make it return an error value.
* Rename ide_get_or_set_dma_base() to ide_pci_dma_base(),
change ordering of its arguments and then export it.
* Export ide_pci_set_master().
* Do complete DMA setup inside ->init_dma method and update ->init_dma
users accordingly.
* Sanitize code for DMA setup in ide_init_port().
v2:
* Fix for CONFIG_BLK_DEV_IDEDMA_PCI=n configs
(from Jiri Slaby <jirislaby@gmail.com>):
Fix following compiler warning by returning EINVAL:
In file included from ANYTHING-INCLUDING-IDE.H:45:
include/linux/ide.h: In function ‘ide_hwif_setup_dma’:
include/linux/ide.h:1022: warning: no return statement in function returning non-void
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Export ide_allocate_dma_engine() and use it in trm290 host driver.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Use hwif->name instead of cds->name in ide_allocate_dma_engine().
* Use pci_name(dev) instead of cds->name in init_dma_pdc202xx().
* Remove no longer needed ->cds field from ide_hwif_t.
v2:
* scc_pata.c also needs to be updated now (noticed by Stephen Rothwell).
There should be no functional changes caused by this patch.
Cc: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Cc: Akira Iguchi <akira2.iguchi@toshiba.co.jp>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Always setup hwif->extra_base in ide_iomio_dma() and remove
no longer needed ->extra field from struct ide_port_info.
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Reserve PCI BARs 0-3 (0-1 for single port controllers) in
ide_pci_enable() and remove ide_hwif_request_regions() call
from ide_device_add_all() (also cleanup resource management
in scc_pata host driver).
* Fix handling of PCI BAR 4 in ide_pci_enable(), then cleanup
ide_iomio_dma() (+ init_hwif_trm290() in trm290 host driver)
and remove ide_release[_iomio]_dma().
v2:
* Fixup trm290 host driver.
v3:
* Because of scc_pata host driver changes we need to call
pci_request_selected_regions() also in setup_mmio_scc().
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
All host drivers using ide_unregister()/module_exit() have been fixed
to manage resources themselves so this function can be removed now.
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add 'unsigned long config' argument to ide_legacy_device_add()
for setting hwif->config_data.
* Use ide_find_port_slot() instead of ide_find_port() in
ide_legacy_device_add().
* Handle IDE_HFLAG_QD_2ND_PORT and IDE_HFLAG_SINGLE host flags in
ide_legacy_device_add().
* Convert qd65xx host driver to use ide_legacy_device_add().
v2:
* Update ali14xx, dtc2278, ht6560b and umc8672 host drivers.
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add ide_legacy_device_add() helper for use by legacy VLB host drivers
(+ convert them to use it).
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Update IDE PMAC host driver to use drive->noprobe instead of hwif->noprobe
and remove hwif->noprobe completely (it is always set to zero now).
There should be no functional changes caused by this patch.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Move hooks for port/host specific methods from ide_hwif_t to
'struct ide_port_ops'.
* Add 'const struct ide_port_ops *port_ops' to 'struct ide_port_info'
and ide_hwif_t.
* Update host drivers and core code accordingly.
While at it:
* Rename ata66_*() cable detect functions to *_cable_detect() to match
the standard naming. (Suggested by Sergei Shtylyov)
v2:
* Fix build for bast-ide. (Noticed by Andrew Morton)
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Avoid a call to find_first_bit if the bitmap size is know at
compile time and small enough to fit in a single long integer.
Modeled after an optimization in the original x86_64-specific
code.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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>
This moves an optimization for searching constant-sized small
bitmaps form x86_64-specific to generic code.
On an i386 defconfig (the x86#testing one), the size of vmlinux hardly
changes with this applied. I have observed only four places where this
optimization avoids a call into find_next_bit:
In the functions return_unused_surplus_pages, alloc_fresh_huge_page,
and adjust_pool_surplus, this patch avoids a call for a 1-bit bitmap.
In __next_cpu a call is avoided for a 32-bit bitmap. That's it.
On x86_64, 52 locations are optimized with a minimal increase in
code size:
Current #testing defconfig:
146 x bsf, 27 x find_next_*bit
text data bss dec hex filename
5392637 846592 724424 6963653 6a41c5 vmlinux
After removing the x86_64 specific optimization for find_next_*bit:
94 x bsf, 79 x find_next_*bit
text data bss dec hex filename
5392358 846592 724424 6963374 6a40ae vmlinux
After this patch (making the optimization generic):
146 x bsf, 27 x find_next_*bit
text data bss dec hex filename
5392396 846592 724424 6963412 6a40d4 vmlinux
[ tglx@linutronix.de: build fixes ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stephen Rothwell reported that linux-next did not build on powerpc64.
make optimized inlining dependent on architecture opt-in.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
add CONFIG_OPTIMIZE_INLINING=y.
allow gcc to optimize the kernel image's size by uninlining
functions that have been marked 'inline'. Previously gcc was
forced by Linux to always-inline these functions via a gcc
attribute:
#define inline inline __attribute__((always_inline))
Especially when the user has already selected
CONFIG_OPTIMIZE_FOR_SIZE=y this can make a huge difference in
kernel image size (using a standard Fedora .config):
text data bss dec hex filename
5613924 562708 3854336 10030968 990f78 vmlinux.before
5486689 562708 3854336 9903733 971e75 vmlinux.after
that's a 2.3% text size reduction (!).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
All host drivers now either set hwif->mmio or reserve continuous
I/O resources so remove no longer needed hwif->straight8 flag
and never reached code for 'hwif->straight8 == 0' case.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
