in scheduler-intense workloads native_read_tsc() overhead accounts for
20% of the system overhead:
659567 system_call 41222.9375
686796 schedule 435.7843
718382 __switch_to 665.1685
823875 switch_mm 4526.7857
1883122 native_read_tsc 55385.9412
9761990 total 2.8468
this is large part due to the rdtsc_barrier() that is done before
and after reading the TSC.
But sched_clock() is not a precise clock in the GTOD sense, using such
barriers is completely pointless. So remove the barriers and only use
them in vget_cycles().
This improves lat_ctx performance by about 5%.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
Revert "x86: default to reboot via ACPI"
x86: align DirectMap in /proc/meminfo
AMD IOMMU: fix lazy IO/TLB flushing in unmap path
x86: add smp_mb() before sending INVALIDATE_TLB_VECTOR
x86: remove VISWS and PARAVIRT around NR_IRQS puzzle
x86: mention ACPI in top-level Kconfig menu
x86: size NR_IRQS on 32-bit systems the same way as 64-bit
x86: don't allow nr_irqs > NR_IRQS
x86/docs: remove noirqbalance param docs
x86: don't use tsc_khz to calculate lpj if notsc is passed
x86, voyager: fix smp_intr_init() compile breakage
AMD IOMMU: fix detection of NP capable IOMMUs
Impact: fix warning message when PARAVIRT is set in config
Remove stale #ifdef components from our IRQ sizing logic.
x86/Voyager is the only holdout.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: make NR_IRQS big enough for system with lots of apic/pins
If lots of IO_APIC's are there (or can be there), size the same way
as 64-bit, depending on MAX_IO_APICS and NR_CPUS.
This fixes the boot problem reported by Ben Hutchings on a 32-bit
server with 5 IO-APICs and 240 IO-APIC pins.
Signed-off-by: Yinghai <yinghai@kernel.org>
Tested-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: improve wakeup affinity on NUMA systems, tweak SMP systems
Given the fixes+tweaks to the wakeup-buddy code, re-tweak the domain
balancing defaults on NUMA and SMP systems.
Turn on SD_WAKE_AFFINE which was off on x86 NUMA - there's no reason
why we would not want to have wakeup affinity across nodes as well.
(we already do this in the standard NUMA template.)
lat_ctx on a NUMA box is particularly happy about this change:
before:
| phoenix:~/l> ./lat_ctx -s 0 2
| "size=0k ovr=2.60
| 2 5.70
after:
| phoenix:~/l> ./lat_ctx -s 0 2
| "size=0k ovr=2.65
| 2 2.07
a 2.75x speedup.
pipe-test is similarly happy about it too:
| phoenix:~/sched-tests> ./pipe-test
| 18.26 usecs/loop.
| 14.70 usecs/loop.
| 14.38 usecs/loop.
| 10.55 usecs/loop. # +WAKE_AFFINE on domain0+domain1
| 8.63 usecs/loop.
| 8.59 usecs/loop.
| 9.03 usecs/loop.
| 8.94 usecs/loop.
| 8.96 usecs/loop.
| 8.63 usecs/loop.
Also:
- disable SD_BALANCE_NEWIDLE on NUMA and SMP domains (keep it for siblings)
- enable SD_WAKE_BALANCE on SMP domains
Sysbench+postgresql improves all around the board, quite significantly:
.28-rc3-11474e2c .28-rc3-11474e2c-tune
-------------------------------------------------
1: 571 688 +17.08%
2: 1236 1206 -2.55%
4: 2381 2642 +9.89%
8: 4958 5164 +3.99%
16: 9580 9574 -0.07%
32: 7128 8118 +12.20%
64: 7342 8266 +11.18%
128: 7342 8064 +8.95%
256: 7519 7884 +4.62%
512: 7350 7731 +4.93%
-------------------------------------------------
SUM: 55412 59341 +6.62%
So it's a win both for the runup portion, the peak area and the tail.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'io-mappings-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
io mapping: clean up #ifdefs
io mapping: improve documentation
i915: use io-mapping interfaces instead of a variety of mapping kludges
resources: add io-mapping functions to dynamically map large device apertures
x86: add iomap_atomic*()/iounmap_atomic() on 32-bit using fixmaps
Impact: fix x86/Voyager build
Looks like this became static on the rest of x86. Fix it up by adding
an external definition to mach-voyager/setup.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: introduce new APIs, separate kmap code from CONFIG_HIGHMEM
This takes the code used for CONFIG_HIGHMEM memory mappings except that
it's designed for dynamic IO resource mapping.
These fixmaps are available even with CONFIG_HIGHMEM turned off.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: change the kexec bootstrap code implementation from assembly to C
This patch transforms the kexec page tables setup code from assembler
code to C code in machine_kexec_prepare. This improves readability and
reduces code line number.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: save .text size when kexec is built in but not loaded
This patch adds an architecture specific struct kimage_arch into
struct kimage. The pointers to page table pages used by kexec are
added to struct kimage_arch. The page tables pages are dynamically
allocated in machine_kexec_prepare instead of statically from BSS
segment. This will save up to 20k memory when kexec image is not
loaded.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: build fix on x86/Voyager
Given commits like this:
| Author: Suresh Siddha <suresh.b.siddha@intel.com>
| Date: Tue Jul 29 10:29:19 2008 -0700
|
| x86, xsave: enable xsave/xrstor on cpus with xsave support
Which deliberately expose boot cpu dependence to pieces of the system,
I think it's time to explicitly have a variable for it to prevent this
continual misassumption that the boot CPU is zero.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: include file dependency cleanup
Fix compile errors of files that include asm/uv/uv_hub.h but do
not include linux/timer.h.
[ such files are not mainline right now. ]
Signed-of-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
To the unsuspecting user it is quite annoying that this broken and
inconsistent with x86-64 definition still exists.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: some new sparse warnings in e820.c etc, but no functional change.
As with regular ioremap, iounmap etc, annotate with __iomem.
Fixes the following sparse warnings, will produce some new ones
elsewhere in arch/x86 that will get worked out over time.
arch/x86/mm/ioremap.c:402:9: warning: cast removes address space of expression
arch/x86/mm/ioremap.c:406:10: warning: cast adds address space to expression (<asn:2>)
arch/x86/mm/ioremap.c:782:19: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
ftrace: fix current_tracer error return
tracing: fix a build error on alpha
ftrace: use a real variable for ftrace_nop in x86
tracing/ftrace: make boot tracer select the sched_switch tracer
tracepoint: check if the probe has been registered
asm-generic: define DIE_OOPS in asm-generic
trace: fix printk warning for u64
ftrace: warning in kernel/trace/ftrace.c
ftrace: fix build failure
ftrace, powerpc, sparc64, x86: remove notrace from arch ftrace file
ftrace: remove ftrace hash
ftrace: remove mcount set
ftrace: remove daemon
ftrace: disable dynamic ftrace for all archs that use daemon
ftrace: add ftrace warn on to disable ftrace
ftrace: only have ftrace_kill atomic
ftrace: use probe_kernel
ftrace: comment arch ftrace code
ftrace: return error on failed modified text.
ftrace: dynamic ftrace process only text section
...
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
lockdep: fix irqs on/off ip tracing
lockdep: minor fix for debug_show_all_locks()
x86: restore the old swiotlb alloc_coherent behavior
x86: use GFP_DMA for 24bit coherent_dma_mask
swiotlb: remove panic for alloc_coherent failure
xen: compilation fix of drivers/xen/events.c on IA64
xen: portability clean up and some minor clean up for xencomm.c
xen: don't reload cr3 on suspend
kernel/resource: fix reserve_region_with_split() section mismatch
printk: remove unused code from kernel/printk.c
APIC_DEBUG is always 2.
need to update inquire_remote_apic to check apic_verbosity with
it instead.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Every call of kvm_set_irq() should offer an irq_source_id, which is
allocated by kvm_request_irq_source_id(). Based on irq_source_id, we
identify the irq source and implement logical OR for shared level
interrupts.
The allocated irq_source_id can be freed by kvm_free_irq_source_id().
Currently, we support at most sizeof(unsigned long) different irq sources.
[Amit: - rebase to kvm.git HEAD
- move definition of KVM_USERSPACE_IRQ_SOURCE_ID to common file
- move kvm_request_irq_source_id to the update_irq ioctl]
[Xiantao: - Add kvm/ia64 stuff and make it work for kvm/ia64 guests]
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
On Thu, Oct 23, 2008 at 04:09:52PM -0700, Alexander Beregalov wrote:
> arch/x86/kernel/built-in.o: In function `iommu_setup':
> pci-dma.c:(.init.text+0x36ad): undefined reference to `forbid_dac'
> pci-dma.c:(.init.text+0x36cc): undefined reference to `forbid_dac'
> pci-dma.c:(.init.text+0x3711): undefined reference to `forbid_dac
This patch partially reverts a patch to add IOMMU support to ia64. The
forbid_dac variable was incorrectly moved to quirks.c, which isn't built
when PCI is disabled.
Tested-by: "Alexander Beregalov" <a.beregalov@gmail.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
dma_alloc_coherent (include/asm-x86/dma-mapping.h) avoids GFP_DMA
allocation first and if the allocated address is not fit for the
device's coherent_dma_mask, then dma_alloc_coherent does GFP_DMA
allocation. This is because dma_alloc_coherent avoids precious GFP_DMA
zone if possible. This is also how the old dma_alloc_coherent
(arch/x86/kernel/pci-dma.c) works.
However, if the coherent_dma_mask of a device is 24bit, there is no
point to go into the above GFP_DMA retry mechanism. We had better use
GFP_DMA in the first place.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: fix section mismatch warning - apic_x2apic_phys
x86: fix section mismatch warning - apic_x2apic_cluster
x86: fix section mismatch warning - apic_x2apic_uv_x
x86: fix section mismatch warning - apic_physflat
x86: fix section mismatch warning - apic_flat
x86: memtest fix use of reserve_early()
x86 syscall.h: fix argument order
x86/tlb_uv: remove strange mc146818rtc include
x86: remove redundant KERN_DEBUG on pr_debug
x86: do_boot_cpu - check if we have ESR register
x86: MAINTAINERS change for AMD microcode patch loader
x86/proc: fix /proc/cpuinfo cpu offline bug
x86: call dmi-quirks for HP Laptops after early-quirks are executed
x86, kexec: fix hang on i386 when panic occurs while console_sem is held
MCE: Don't run 32bit machine checks with interrupts on
x86: SB600: skip IRQ0 override if it is not routed to INT2 of IOAPIC
x86: make variables static
* 'x86/um-header' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits)
x86: canonicalize remaining header guards
x86: drop double underscores from header guards
x86: Fix ASM_X86__ header guards
x86, um: get rid of uml-config.h
x86, um: get rid of arch/um/Kconfig.arch
x86, um: get rid of arch/um/os symlink
x86, um: get rid of excessive includes of uml-config.h
x86, um: get rid of header symlinks
x86, um: merge Kconfig.i386 and Kconfig.x86_64
x86, um: get rid of sysdep symlink
x86, um: trim the junk from uml ptrace-*.h
x86, um: take vm-flags.h to sysdep
x86, um: get rid of uml asm/arch
x86, um: get rid of uml highmem.h
x86, um: get rid of uml unistd.h
x86, um: get rid of system.h -> system.h include
x86, um: uml atomic.h is not needed anymore
x86, um: untangle uml ldt.h
x86, um: get rid of more uml asm/arch uses
x86, um: remove dead header (uml module-generic.h; never used these days)
...
Canonicalize a few remaining header guards, with the exception for
those which are still in subarchitecture directories.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Drop double underscores from header guards in arch/x86/include. They
are used inconsistently, and are not necessary.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:
a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Ingo Molnar