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2011-11-20Merge branch 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM guest: prevent tracing recursion with kvmclock Revert "KVM: PPC: Add support for explicit HIOR setting" KVM: VMX: Check for automatic switch msr table overflow KVM: VMX: Add support for guest/host-only profiling KVM: VMX: add support for switching of PERF_GLOBAL_CTRL KVM: s390: announce SYNC_MMU KVM: s390: Fix tprot locking KVM: s390: handle SIGP sense running intercepts KVM: s390: Fix RUNNING flag misinterpretation
2011-11-20KVM guest: prevent tracing recursion with kvmclockAvi Kivity
Prevent tracing of preempt_disable() in get_cpu_var() in kvm_clock_read(). When CONFIG_DEBUG_PREEMPT is enabled, preempt_disable/enable() are traced and this causes the function_graph tracer to go into an infinite recursion. By open coding the preempt_disable() around the get_cpu_var(), we can use the notrace version which prevents preempt_disable/enable() from being traced and prevents the recursion. Based on a similar patch for Xen from Jeremy Fitzhardinge. Tested-by: Gleb Natapov <gleb@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-11-18Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: random: Fix handing of arch_get_random_long in get_random_bytes() x86: Call stop_machine_text_poke() on all CPUs x86, ioapic: Only print ioapic debug information for IRQs belonging to an ioapic chip x86/mrst: Avoid reporting wrong nmi status x86/mrst: Add support for Penwell clock calibration x86/apic: Allow use of lapic timer early calibration result x86/apic: Do not clear nr_irqs_gsi if no legacy irqs x86/platform: Add a wallclock_init func to x86_platforms ops x86/mce: Make mce_chrdev_ops 'static const'
2011-11-18Merge branch 'stable/for-linus-fixes-3.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/for-linus-fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen-gntalloc: signedness bug in add_grefs() xen-gntalloc: integer overflow in gntalloc_ioctl_alloc() xen-gntdev: integer overflow in gntdev_alloc_map() xen:pvhvm: enable PVHVM VCPU placement when using more than 32 CPUs. xen/balloon: Avoid OOM when requesting highmem xen: Remove hanging references to CONFIG_XEN_PLATFORM_PCI xen: map foreign pages for shared rings by updating the PTEs directly
2011-11-17KVM: VMX: Check for automatic switch msr table overflowGleb Natapov
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-11-17KVM: VMX: Add support for guest/host-only profilingGleb Natapov
Support guest/host-only profiling by switch perf msrs on a guest entry if needed. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-11-17KVM: VMX: add support for switching of PERF_GLOBAL_CTRLGleb Natapov
Some cpus have special support for switching PERF_GLOBAL_CTRL msr. Add logic to detect if such support exists and works properly and extend msr switching code to use it if available. Also extend number of generic msr switching entries to 8. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-11-16xen:pvhvm: enable PVHVM VCPU placement when using more than 32 CPUs.Zhenzhong Duan
PVHVM running with more than 32 vcpus and pv_irq/pv_time enabled need VCPU placement to work, or else it will softlockup. CC: stable@kernel.org Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-16xen: map foreign pages for shared rings by updating the PTEs directlyDavid Vrabel
When mapping a foreign page with xenbus_map_ring_valloc() with the GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and pass a pointer to the PTE (in init_mm). After the page is mapped, the usual fault mechanism can be used to update additional MMs. This allows the vmalloc_sync_all() to be removed from alloc_vm_area(). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> [v1: Squashed fix by Michal for no-mmu case] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2011-11-14x86: Call stop_machine_text_poke() on all CPUsRabin Vincent
It appears that stop_machine_text_poke() wants to be called on all CPUs, like it's done from text_poke_smp(). Fix text_poke_smp_batch() to do this. Signed-off-by: Rabin Vincent <rabin@rab.in> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1319702072-32676-1-git-send-email-rabin@rab.in Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-11bma023: Add SFI translation for this deviceWilliam Douglas
This needed the sfi IRQ 0xFF fix to go in first. It simply plumbs in the bma023 driver with the firmware naming of it. Signed-off-by: William Douglas <william.douglas@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-11vrtc: change its year offset from 1960 to 1972Feng Tang
Real world year equals the value in vrtc YEAR register plus an offset. We used 1960 as the offset to make leap year consistent, but for a device's first use, its YEAR register is 0 and the system year will be parsed as 1960 which is not a valid UNIX time and will cause many applications to fail mysteriously. So we use 1972 instead to fix this issue. Updated patch which adds a sanity check suggested by Mathias This isn't a change in behaviour for systems, because 1972 is the one we actually use. It's the old version in upstream which is out of sync with all devices. Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-11ce4100: fix a build errorZhang Rui
Fix a build error. CE4100 with no serial errors because the alternate function is only a prototype not a null function as intended. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-10x86, ioapic: Only print ioapic debug information for IRQs belonging to an ↵Mathias Nyman
ioapic chip with "apic=verbose" the print_IO_APIC() function tries to print IRQ to pin mappings for every active irq. It assumes chip_data is of type irq_cfg and may cause an oops if not. As the print_IO_APIC() is called from a late_initcall other chained irq chips may already be registered with custom chip_data information, causing an oops. This is the case with intel MID SoC devices with gpio demuxers registered as irq_chips. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> [ -v2: fixed build failure ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10x86/mrst: Avoid reporting wrong nmi statusJacob Pan
Moorestown/Medfield platform does not have port 0x61 to report NMI status, nor does it have external NMI sources. The only NMI sources are from lapic, as results of perf counter overflow or IPI, e.g. NMI watchdog or spin lock debug. Reading port 0x61 on Moorestown will return 0xff which misled NMI handlers to false critical errors such memory parity error. The subsequent ioport access for NMI handling can also cause undefined behavior on Moorestown. This patch allows kernel process NMI due to watchdog or backrace dump without unnecessary hangs. Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> [hand applied] Signed-off-by: Alan Cox <alan@linux.intel.com>
2011-11-10x86/mrst: Add support for Penwell clock calibrationDirk Brandewie
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10x86/apic: Allow use of lapic timer early calibration resultJacob Pan
lapic timer calibration can be combined with tsc in platform specific calibration functions. if such calibration result is obtained early, we can skip the redundant calibration loops. Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10x86/apic: Do not clear nr_irqs_gsi if no legacy irqsJacob Pan
nr_legacy_irqs is set in probe_nr_irqs_gsi, we should not clear it after that. Otherwise, the result is that MSI irqs will be allocated from the wrong range for the systems without legacy PIC. Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10x86/platform: Add a wallclock_init func to x86_platforms opsFeng Tang
Some wall clock devices use MMIO based HW register, this new function will give them a chance to do some initialization work before their get/set_time service get called. Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-08x86/mce: Make mce_chrdev_ops 'static const'Luck, Tony
Arjan would like to make struct file_operations const, but mce-inject directly writes to the mce_chrdev_ops to install its write handler. In an ideal world mce-inject would have its own character device, but we have a sizable legacy of test scripts that hardwire "/dev/mcelog", so it would be painful to switch to a separate device now. Instead, this patch switches to a stub function in the mce code, with a registration helper that mce-inject can call when it is loaded. Note that this would also allow for a sane process to allow mce-inject to be unloaded again (with an unregister function, and appropriate module_{get,put}() calls), but that is left for potential future patches. Reported-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/4eb2e1971326651a3b@agluck-desktop.sc.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-07Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: cpuidle: Single/Global registration of idle states cpuidle: Split cpuidle_state structure and move per-cpu statistics fields cpuidle: Remove CPUIDLE_FLAG_IGNORE and dev->prepare() cpuidle: Move dev->last_residency update to driver enter routine; remove dev->last_state ACPI: Fix CONFIG_ACPI_DOCK=n compiler warning ACPI: Export FADT pm_profile integer value to userspace thermal: Prevent polling from happening during system suspend ACPI: Drop ACPI_NO_HARDWARE_INIT ACPI atomicio: Convert width in bits to bytes in __acpi_ioremap_fast() PNPACPI: Simplify disabled resource registration ACPI: Fix possible recursive locking in hwregs.c ACPI: use kstrdup() mrst pmu: update comment tools/power turbostat: less verbose debugging
2011-11-06Merge branch 'upstream/jump-label-noearly' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen * 'upstream/jump-label-noearly' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: jump-label: initialize jump-label subsystem much earlier x86/jump_label: add arch_jump_label_transform_static() s390/jump-label: add arch_jump_label_transform_static() jump_label: add arch_jump_label_transform_static() to optimise non-live code updates sparc/jump_label: drop arch_jump_label_text_poke_early() x86/jump_label: drop arch_jump_label_text_poke_early() jump_label: if a key has already been initialized, don't nop it out stop_machine: make stop_machine safe and efficient to call early jump_label: use proper atomic_t initializer Conflicts: - arch/x86/kernel/jump_label.c Added __init_or_module to arch_jump_label_text_poke_early vs removal of that function entirely - kernel/stop_machine.c same patch ("stop_machine: make stop_machine safe and efficient to call early") merged twice, with whitespace fix in one version
2011-11-06Merge branch 'upstream/xen-settime' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen * 'upstream/xen-settime' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: xen/dom0: set wallclock time in Xen xen: add dom0_op hypercall xen/acpi: Domain0 acpi parser related platform hypercall
2011-11-06Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
2011-11-06Merge branch 'trivial' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild * 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: scsi: drop unused Kconfig symbol pci: drop unused Kconfig symbol stmmac: drop unused Kconfig symbol x86: drop unused Kconfig symbol powerpc: drop unused Kconfig symbols powerpc: 40x: drop unused Kconfig symbol mips: drop unused Kconfig symbols openrisc: drop unused Kconfig symbols arm: at91: drop unused Kconfig symbol samples: drop unused Kconfig symbol m32r: drop unused Kconfig symbol score: drop unused Kconfig symbols sh: drop unused Kconfig symbol um: drop unused Kconfig symbol sparc: drop unused Kconfig symbol alpha: drop unused Kconfig symbol Fix up trivial conflict in drivers/net/ethernet/stmicro/stmmac/Kconfig as per Michal: the STMMAC_DUAL_MAC config variable is still unused and should be deleted.
2011-11-06Merge branch 'stable/vmalloc-3.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: net: xen-netback: use API provided by xenbus module to map rings block: xen-blkback: use API provided by xenbus module to map rings xen: use generic functions instead of xen_{alloc, free}_vm_area()
2011-11-06mrst pmu: update commentLen Brown
referenced MeeGo, in particular, but really means Linux, in general. Signed-off-by: Len Brown <len.brown@intel.com>
2011-11-03Merge branch 'for-next' of git://git.infradead.org/users/sameo/mfd-2.6Linus Torvalds
* 'for-next' of git://git.infradead.org/users/sameo/mfd-2.6: (80 commits) mfd: Fix missing abx500 header file updates mfd: Add missing <linux/io.h> include to intel_msic x86, mrst: add platform support for MSIC MFD driver mfd: Expose TurnOnStatus in ab8500 sysfs mfd: Remove support for early drop ab8500 chip mfd: Add support for ab8500 v3.3 mfd: Add ab8500 interrupt disable hook mfd: Convert db8500-prcmu panic() into pr_crit() mfd: Refactor db8500-prcmu request_clock() function mfd: Rename db8500-prcmu init function mfd: Fix db5500-prcmu defines mfd: db8500-prcmu voltage domain consumers additions mfd: db8500-prcmu reset code retrieval mfd: db8500-prcmu tweak for modem wakeup mfd: Add db8500-pcmu watchdog accessor functions for watchdog mfd: hwacc power state db8500-prcmu accessor mfd: Add db8500-prcmu accessors for PLL and SGA clock mfd: Move to the new db500 PRCMU API mfd: Create a common interface for dbx500 PRCMU drivers mfd: Initialize DB8500 PRCMU regs ... Fix up trivial conflicts in arch/arm/mach-imx/mach-mx31moboard.c arch/arm/mach-omap2/board-omap3beagle.c arch/arm/mach-u300/include/mach/irqs.h drivers/mfd/wm831x-spi.c
2011-11-02Merge branch 'linux_next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac * 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac: (21 commits) MAINTAINERS: add an entry for Edac Sandy Bridge driver edac: tag sb_edac as EXPERIMENTAL, as it requires more testing EDAC: Fix incorrect edac mode reporting in sb_edac edac: sb_edac: Add it to the building system edac: Add an experimental new driver to support Sandy Bridge CPU's i7300_edac: Fix error cleanup logic i7core_edac: Initialize memory name with cpu, channel, bank i7core_edac: Fix compilation on 32 bits arch i7core_edac: scrubbing fixups EDAC: Correct Kconfig dependencies i7core_edac: return -ENODEV if no MC is found i7core_edac: use edac's own way to print errors MAINTAINERS: remove dropped edac_mce.* from the file i7core_edac: Drop the edac_mce facility x86, MCE: Use notifier chain only for MCE decoding EDAC i7core: Use mce socketid for better compatibility i7core_edac: Don't enable memory scrubbing for Xeon 35xx i7core_edac: Add scrubbing support edac: Move edac main structs to include/linux/edac.h i7core_edac: Fix oops when trying to inject errors ...
2011-11-02Merge branch 'akpm' (Andrew's incoming - part two)Linus Torvalds
Says Andrew: "60 patches. That's good enough for -rc1 I guess. I have quite a lot of detritus to be rechecked, work through maintainers, etc. - most of the remains of MM - rtc - various misc - cgroups - memcg - cpusets - procfs - ipc - rapidio - sysctl - pps - w1 - drivers/misc - aio" * akpm: (60 commits) memcg: replace ss->id_lock with a rwlock aio: allocate kiocbs in batches drivers/misc/vmw_balloon.c: fix typo in code comment drivers/misc/vmw_balloon.c: determine page allocation flag can_sleep outside loop w1: disable irqs in critical section drivers/w1/w1_int.c: multiple masters used same init_name drivers/power/ds2780_battery.c: fix deadlock upon insertion and removal drivers/power/ds2780_battery.c: add a nolock function to w1 interface drivers/power/ds2780_battery.c: create central point for calling w1 interface w1: ds2760 and ds2780, use ida for id and ida_simple_get() to get it pps gpio client: add missing dependency pps: new client driver using GPIO pps: default echo function include/linux/dma-mapping.h: add dma_zalloc_coherent() sysctl: make CONFIG_SYSCTL_SYSCALL default to n sysctl: add support for poll() RapidIO: documentation update drivers/net/rionet.c: fix ethernet address macros for LE platforms RapidIO: fix potential null deref in rio_setup_device() RapidIO: add mport driver for Tsi721 bridge ...
2011-11-02thp: share get_huge_page_tail()Andrea Arcangeli
This avoids duplicating the function in every arch gup_fast. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <jweiner@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02mm: thp: tail page refcounting fixAndrea Arcangeli
Michel while working on the working set estimation code, noticed that calling get_page_unless_zero() on a random pfn_to_page(random_pfn) wasn't safe, if the pfn ended up being a tail page of a transparent hugepage under splitting by __split_huge_page_refcount(). He then found the problem could also theoretically materialize with page_cache_get_speculative() during the speculative radix tree lookups that uses get_page_unless_zero() in SMP if the radix tree page is freed and reallocated and get_user_pages is called on it before page_cache_get_speculative has a chance to call get_page_unless_zero(). So the best way to fix the problem is to keep page_tail->_count zero at all times. This will guarantee that get_page_unless_zero() can never succeed on any tail page. page_tail->_mapcount is guaranteed zero and is unused for all tail pages of a compound page, so we can simply account the tail page references there and transfer them to tail_page->_count in __split_huge_page_refcount() (in addition to the head_page->_mapcount). While debugging this s/_count/_mapcount/ change I also noticed get_page is called by direct-io.c on pages returned by get_user_pages. That wasn't entirely safe because the two atomic_inc in get_page weren't atomic. As opposed to other get_user_page users like secondary-MMU page fault to establish the shadow pagetables would never call any superflous get_page after get_user_page returns. It's safer to make get_page universally safe for tail pages and to use get_page_foll() within follow_page (inside get_user_pages()). get_page_foll() is safe to do the refcounting for tail pages without taking any locks because it is run within PT lock protected critical sections (PT lock for pte and page_table_lock for pmd_trans_huge). The standard get_page() as invoked by direct-io instead will now take the compound_lock but still only for tail pages. The direct-io paths are usually I/O bound and the compound_lock is per THP so very finegrined, so there's no risk of scalability issues with it. A simple direct-io benchmarks with all lockdep prove locking and spinlock debugging infrastructure enabled shows identical performance and no overhead. So it's worth it. Ideally direct-io should stop calling get_page() on pages returned by get_user_pages(). The spinlock in get_page() is already optimized away for no-THP builds but doing get_page() on tail pages returned by GUP is generally a rare operation and usually only run in I/O paths. This new refcounting on page_tail->_mapcount in addition to avoiding new RCU critical sections will also allow the working set estimation code to work without any further complexity associated to the tail page refcounting with THP. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: Michel Lespinasse <walken@google.com> Reviewed-by: Michel Lespinasse <walken@google.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <jweiner@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: <stable@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02Merge branch 'for-linus' of git://github.com/richardweinberger/linuxLinus Torvalds
* 'for-linus' of git://github.com/richardweinberger/linux: (90 commits) um: fix ubd cow size um: Fix kmalloc argument order in um/vdso/vma.c um: switch to use of drivers/Kconfig UserModeLinux-HOWTO.txt: fix a typo UserModeLinux-HOWTO.txt: remove ^H characters um: we need sys/user.h only on i386 um: merge delay_{32,64}.c um: distribute exports to where exported stuff is defined um: kill system-um.h um: generic ftrace.h will do... um: segment.h is x86-only and needed only there um: asm/pda.h is not needed anymore um: hw_irq.h can go generic as well um: switch to generic-y um: clean Kconfig up a bit um: a couple of missing dependencies... um: kill useless argument of free_chan() and free_one_chan() um: unify ptrace_user.h um: unify KSTK_... um: fix gcov build breakage ...
2011-11-02um: Fix kmalloc argument order in um/vdso/vma.cDave Jones
kmalloc size is 1st arg, not second. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Richard Weinberger <richard@nod.at> Cc: <stable@kernel.org> # 3.0.x [richard@nod.at: on 3.0 the to be patched file is arch/um/sys-x86_64/vdso/vma.c]
2011-11-02um: we need sys/user.h only on i386Richard Weinberger
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge delay_{32,64}.cRichard Weinberger
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: kill system-um.hAl Viro
most of it belonged in irqflags.h, actually Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: segment.h is x86-only and needed only thereAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: unify ptrace_user.hAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: unify KSTK_...Al Viro
... and switch get_thread_register() to HOST_... for register numbers Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: fix gcov build breakageAl Viro
a) exports in gmon_syms.c duplicate kernel/gcov/* ones b) excluding -pg in vdso compile is not enough - -fprofile-arcs and -ftest-coverage also needs to be excluded Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: irq_vectors.h just shadows x86 oneAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: required-features.h is there only to shadow x86 one...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: asm/apic.h is there only to shadow the x86 one...Al Viro
... so take it to arch/um/x86/asm. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: take ldt.h to arch/x86/um/asm/mm_context.hAl Viro
it's x86-only and we have no business playing with it in asm/mmu.h; make the latter have struct uml_arch_mm_context arch; instead of struct uml_ldt ldt; and let arch/<subarch>/um/asm/mm_context.h decide what'll be in there. While we are at it, kill host_ldt.h - it's not needed in part of places that include it (we want asm/ldt.h in those) and it can be trivially expanded into the single remaining one. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge signal_{32,64}.cAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: no need to play with save_sp in signal frame setup anymoreAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: increase stack growth cushion in pagefaultAl Viro
analog of [PATCH] i386: let usermode execute the "enter" instruction from circa 2006. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge HOST_... of registers common on i386 and amd64Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: sanitize paths in sys_call_table* includesAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>