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2015-09-23userfaultfd: revert "userfaultfd: waitqueue: add nr wake parameter to ↵Andrea Arcangeli1-3/+2
__wake_up_locked_key" This reverts commit 51360155eccb907ff8635bd10fc7de876408c2e0 and adapts fs/userfaultfd.c to use the old version of that function. It didn't look robust to call __wake_up_common with "nr == 1" when we absolutely require wakeall semantics, but we've full control of what we insert in the two waitqueue heads of the blocked userfaults. No exclusive waitqueue risks to be inserted into those two waitqueue heads so we can as well stick to "nr == 1" of the old code and we can rely purely on the fact no waitqueue inserted in one of the two waitqueue heads we must enforce as wakeall, has wait->flags WQ_FLAG_EXCLUSIVE set. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Thierry Reding <treding@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-22Merge branch 'for-4.3-fixes' of ↵Linus Torvalds3-25/+22
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "The threadgroup locking changes which went in during 4.2 devel cycle added write locking of a percpu_rwsem in cgroup task migration path; unfortunately, that involved expedited rcu syncing which turned out to be too slow and heavy for certain workloads. The patchset which is dependent on this one didn't get committed during that devel cycle, so these two patches can be reverted safely. Oleg reworked percpu_rwsem for 4.4 so that the writer path is a lot lighter. The reported issue goes away with Oleg's reworked percpu_rwsem and I'll reapply these patches on the for-4.4 branch so that they can land together with Oleg's changes" * 'for-4.3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: Revert "sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem" Revert "cgroup: simplify threadgroup locking"
2015-09-21security: fix typo in security_task_prctlJann Horn1-1/+1
Signed-off-by: Jann Horn <jann@thejh.net> Reviewed-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-20Merge tag 'pm+acpi-4.3-rc2' of ↵Linus Torvalds4-4/+31
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI updates from Rafael Wysocki: "Included are: a somewhat late devfreq update which however is mostly fixes and cleanups with one new thing only (the PPMUv2 support on Exynos5433), an ACPI cpufreq driver fixup and two ACPI core cleanups related to preprocessor directives. Specifics: - Fix a memory allocation size in the devfreq core (Xiaolong Ye). - Fix a mistake in the exynos-ppmu DT binding (Javier Martinez Canillas). - Add support for PPMUv2 ((Platform Performance Monitoring Unit version 2.0) on the Exynos5433 SoCs (Chanwoo Choi). - Fix a type casting bug in the Exynos PPMU code (MyungJoo Ham). - Assorted devfreq code cleanups and optimizations (Javi Merino, MyungJoo Ham, Viresh Kumar). - Fix up the ACPI cpufreq driver to use a more lightweight way to get to its private data in the ->get() callback (Rafael J Wysocki). - Fix a CONFIG_ prefix bug in one of the ACPI drivers and make the ACPI subsystem use IS_ENABLED() instead of #ifdefs in function bodies (Sudeep Holla)" * tag 'pm+acpi-4.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: acpi-cpufreq: Use cpufreq_cpu_get_raw() in ->get() ACPI: Eliminate CONFIG_.*{, _MODULE} #ifdef in favor of IS_ENABLED() ACPI: int340x_thermal: add missing CONFIG_ prefix PM / devfreq: Fix incorrect type issue. PM / devfreq: tegra: Update governor to use devfreq_update_stats() PM / devfreq: comments for get_dev_status usage updated PM / devfreq: drop comment about thermal setting max_freq PM / devfreq: cache the last call to get_dev_status() PM / devfreq: Drop unlikely before IS_ERR(_OR_NULL) PM / devfreq: exynos-ppmu: bit-wise operation bugfix. PM / devfreq: exynos-ppmu: Update documentation to support PPMUv2 PM / devfreq: exynos-ppmu: Add the support of PPMUv2 for Exynos5433 PM / devfreq: event: Remove incorrect property in exynos-ppmu DT binding
2015-09-20Merge tag 'for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma Pull rdma fixes from Doug Ledford: "The new hfi1 driver in staging/rdma has had a number of fixup patches since being added to the tree. This is the first batch of those fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: IB/hfi: Properly set permissions for user device files IB/hfi1: mask vs shift confusion IB/hfi1: clean up some defines IB/hfi1: info leak in get_ctxt_info() IB/hfi1: fix a locking bug IB/hfi1: checking for NULL instead of IS_ERR IB/hfi1: fix sdma_descq_cnt parameter parsing IB/hfi1: fix copy_to/from_user() error handling IB/hfi1: fix pstateinfo from returning improperly byteswapped value
2015-09-20Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: - a boot regression (since v4.2) fix for some ARM configurations from Tyler - regression (since v4.1) fixes for mkfs.xfs on a DAX enabled device from Jeff. These are tagged for -stable. - a pair of locking fixes from Axel that are hidden from lockdep since they involve device_lock(). The "btt" one is tagged for -stable, the other only applies to the new "pfn" mechanism in v4.3. - a fix for the pmem ->rw_page() path to use wmb_pmem() from Ross. * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: mm: fix type cast in __pfn_to_phys() pmem: add proper fencing to pmem_rw_page() libnvdimm: pfn_devs: Fix locking in namespace_store libnvdimm: btt_devs: Fix locking in namespace_store blockdev: don't set S_DAX for misaligned partitions dax: fix O_DIRECT I/O to the last block of a blockdev
2015-09-20Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+50
Pull block updates from Jens Axboe: "This is a bit bigger than it should be, but I could (did) not want to send it off last week due to both wanting extra testing, and expecting a fix for the bounce regression as well. In any case, this contains: - Fix for the blk-merge.c compilation warning on gcc 5.x from me. - A set of back/front SG gap merge fixes, from me and from Sagi. This ensures that we honor SG gapping for integrity payloads as well. - Two small fixes for null_blk from Matias, fixing a leak and a capacity propagation issue. - A blkcg fix from Tejun, fixing a NULL dereference. - A fast clone optimization from Ming, fixing a performance regression since the arbitrarily sized bio's were introduced. - Also from Ming, a regression fix for bouncing IOs" * 'for-linus' of git://git.kernel.dk/linux-block: block: fix bounce_end_io block: blk-merge: fast-clone bio when splitting rw bios block: blkg_destroy_all() should clear q->root_blkg and ->root_rl.blkg block: Copy a user iovec if it includes gaps block: Refuse adding appending a gapped integrity page to a bio block: Refuse request/bio merges with gaps in the integrity payload block: Check for gaps on front and back merges null_blk: fix wrong capacity when bs is not 512 bytes null_blk: fix memory leak on cleanup block: fix bogus compiler warnings in blk-merge.c
2015-09-19mm: fix type cast in __pfn_to_phys()Tyler Baker1-1/+1
The various definitions of __pfn_to_phys() have been consolidated to use a generic macro in include/asm-generic/memory_model.h. This hit mainline in the form of 012dcef3f058 "mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h". When the generic macro was implemented the type cast to phys_addr_t was dropped which caused boot regressions on ARM platforms with more than 4GB of memory and LPAE enabled. It was suggested to use PFN_PHYS() defined in include/linux/pfn.h as provides the correct logic and avoids further duplication. Reported-by: kernelci.org bot <bot@kernelci.org> Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Tyler Baker <tyler.baker@linaro.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-09-19Merge branch 'acpi-bus'Rafael J. Wysocki2-3/+3
* acpi-bus: ACPI: Eliminate CONFIG_.*{, _MODULE} #ifdef in favor of IS_ENABLED() ACPI: int340x_thermal: add missing CONFIG_ prefix
2015-09-19Merge branches 'pm-cpufreq' and 'pm-devfreq'Rafael J. Wysocki2-1/+28
* pm-cpufreq: cpufreq: acpi-cpufreq: Use cpufreq_cpu_get_raw() in ->get() * pm-devfreq: PM / devfreq: Fix incorrect type issue. PM / devfreq: tegra: Update governor to use devfreq_update_stats() PM / devfreq: comments for get_dev_status usage updated PM / devfreq: drop comment about thermal setting max_freq PM / devfreq: cache the last call to get_dev_status() PM / devfreq: Drop unlikely before IS_ERR(_OR_NULL) PM / devfreq: exynos-ppmu: bit-wise operation bugfix. PM / devfreq: exynos-ppmu: Update documentation to support PPMUv2 PM / devfreq: exynos-ppmu: Add the support of PPMUv2 for Exynos5433 PM / devfreq: event: Remove incorrect property in exynos-ppmu DT binding
2015-09-18Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-5/+1
Pull KVM fixes from Paolo Bonzini: "Mostly stable material, a lot of ARM fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits) sched: access local runqueue directly in single_task_running arm/arm64: KVM: Remove 'config KVM_ARM_MAX_VCPUS' arm64: KVM: Remove all traces of the ThumbEE registers arm: KVM: Disable virtual timer even if the guest is not using it arm64: KVM: Disable virtual timer even if the guest is not using it arm/arm64: KVM: vgic: Check for !irqchip_in_kernel() when mapping resources KVM: s390: Replace incorrect atomic_or with atomic_andnot arm: KVM: Fix incorrect device to IPA mapping arm64: KVM: Fix user access for debug registers KVM: vmx: fix VPID is 0000H in non-root operation KVM: add halt_attempted_poll to VCPU stats kvm: fix zero length mmio searching kvm: fix double free for fast mmio eventfd kvm: factor out core eventfd assign/deassign logic kvm: don't try to register to KVM_FAST_MMIO_BUS for non mmio eventfd KVM: make the declaration of functions within 80 characters KVM: arm64: add workaround for Cortex-A57 erratum #852523 KVM: fix polling for guest halt continued even if disable it arm/arm64: KVM: Fix PSCI affinity info return value for non valid cores arm64: KVM: set {v,}TCR_EL2 RES1 bits ...
2015-09-18IB/hfi1: fix pstateinfo from returning improperly byteswapped valueIra Weiny1-2/+2
Byteswap link_width_downgrade_*_active values before sending on the wire. In addition properly define the Port State Info structure. Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Reviewed-by: Christian Gomez <christian.gomez@intel.com> Signed-off-by: Rimmer, Todd <todd.rimmer@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2015-09-18Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds3-65/+59
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "This is a rather large update post rc1 due to the final steps of cleanups and API changes which had to wait for the preparatory patches to hit your tree. - Regression fixes for ARM GIC irqchips - Regression fixes and lockdep anotations for renesas irq chips - The leftovers of the cleanup and preparatory patches which have been ignored by maintainers - Final conversions of the newly merged users of obsolete APIs - Final removal of obsolete APIs - Final removal of ARM artifacts which had been introduced during the conversion of ARM to the generic interrupt code. - Final split of the irq_data into chip specific and common data to reflect the needs of hierarchical irq domains. - Treewide removal of the first argument of interrupt flow handlers, i.e. the irq number, which is not used by the majority of handlers and simple to retrieve from the other argument the irq descriptor. - A few comment updates and build warning fixes" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) arm64: Remove ununsed set_irq_flags ARM: Remove ununsed set_irq_flags sh: Kill off set_irq_flags usage irqchip: Kill off set_irq_flags usage gpu/drm: Kill off set_irq_flags usage genirq: Remove irq argument from irq flow handlers genirq: Move field 'msi_desc' from irq_data into irq_common_data genirq: Move field 'affinity' from irq_data into irq_common_data genirq: Move field 'handler_data' from irq_data into irq_common_data genirq: Move field 'node' from irq_data into irq_common_data irqchip/gic-v3: Use IRQD_FORWARDED_TO_VCPU flag irqchip/gic: Use IRQD_FORWARDED_TO_VCPU flag genirq: Provide IRQD_FORWARDED_TO_VCPU status flag genirq: Simplify irq_data_to_desc() genirq: Remove __irq_set_handler_locked() pinctrl/pistachio: Use irq_set_handler_locked gpio: vf610: Use irq_set_handler_locked powerpc/mpc8xx: Use irq_set_handler_locked() powerpc/ipic: Use irq_set_handler_locked() powerpc/cpm2: Use irq_set_handler_locked() ...
2015-09-17Merge branch 'for-linus' of ↵Linus Torvalds2-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph fixes from Sage Weil: "These are both fixes to the new and improved keepalive2 behavior" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: libceph: advertise support for keepalive2 libceph: don't access invalid memory in keepalive2 path
2015-09-17Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds1-24/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "A fix for an abs()/abs64() bug that caused too slow NTP convergence on 32-bit kernels, plus a removal of an obsolete clockevents driver facility after all users got converted during the merge window" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clockevents: Remove unused set_mode() callback time: Fix timekeeping_freqadjust()'s incorrect use of abs() instead of abs64()
2015-09-17Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "A migrate_tasks() locking fix, and a late-coming nohz change plus a nohz debug check" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: 'Annotate' migrate_tasks() nohz: Assert existing housekeepers when nohz full enabled nohz: Affine unpinned timers to housekeepers
2015-09-17libceph: advertise support for keepalive2Ilya Dryomov1-0/+1
We are the client, but advertise keepalive2 anyway - for consistency, if nothing else. In the future the server might want to know whether its clients support keepalive2. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Yan, Zheng <zyan@redhat.com>
2015-09-17libceph: don't access invalid memory in keepalive2 pathIlya Dryomov1-1/+3
This struct ceph_timespec ceph_ts; ... con_out_kvec_add(con, sizeof(ceph_ts), &ceph_ts); wraps ceph_ts into a kvec and adds it to con->out_kvec array, yet ceph_ts becomes invalid on return from prepare_write_keepalive(). As a result, we send out bogus keepalive2 stamps. Fix this by encoding into a ceph_timespec member, similar to how acks are read and written. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Yan, Zheng <zyan@redhat.com>
2015-09-17Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds2-8/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Ingo Molnar: "Spinlock performance regression fix, plus documentation fixes" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/static_keys: Fix up the static keys documentation locking/qspinlock/x86: Only emit the test-and-set fallback when building guest support locking/qspinlock/x86: Fix performance regression under unaccelerated VMs locking/static_keys: Fix a silly typo
2015-09-17Merge tag 'kvm-arm-for-4.3-rc2-2' of ↵Paolo Bonzini1-5/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master Second set of KVM/ARM changes for 4.3-rc2 - Workaround for a Cortex-A57 erratum - Bug fix for the debugging infrastructure - Fix for 32bit guests with more than 4GB of address space on a 32bit host - A number of fixes for the (unusual) case when we don't use the in-kernel GIC emulation - Removal of ThumbEE handling on arm64, since these have been dropped from the architecture before anyone actually ever built a CPU - Remove the KVM_ARM_MAX_VCPUS limitation which has become fairly pointless
2015-09-17arm/arm64: KVM: Remove 'config KVM_ARM_MAX_VCPUS'Ming Lei1-5/+1
This patch removes config option of KVM_ARM_MAX_VCPUS, and like other ARCHs, just choose the maximum allowed value from hardware, and follows the reasons: 1) from distribution view, the option has to be defined as the max allowed value because it need to meet all kinds of virtulization applications and need to support most of SoCs; 2) using a bigger value doesn't introduce extra memory consumption, and the help text in Kconfig isn't accurate because kvm_vpu structure isn't allocated until request of creating VCPU is sent from QEMU; 3) the main effect is that the field of vcpus[] in 'struct kvm' becomes a bit bigger(sizeof(void *) per vcpu) and need more cache lines to hold the structure, but 'struct kvm' is one generic struct, and it has worked well on other ARCHs already in this way. Also, the world switch frequecy is often low, for example, it is ~2000 when running kernel building load in VM from APM xgene KVM host, so the effect is very small, and the difference can't be observed in my test at all. Cc: Dann Frazier <dann.frazier@canonical.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-09-16Revert "sched, cgroup: replace signal_struct->group_rwsem with a global ↵Tejun Heo3-25/+22
percpu_rwsem" This reverts commit d59cfc09c32a2ae31f1c3bc2983a0cd79afb3f14. d59cfc09c32a ("sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem") and b5ba75b5fc0e ("cgroup: simplify threadgroup locking") changed how cgroup synchronizes against task fork and exits so that it uses global percpu_rwsem instead of per-process rwsem; unfortunately, the write [un]lock paths of percpu_rwsem always involve synchronize_rcu_expedited() which turned out to be too expensive. Improvements for percpu_rwsem are scheduled to be merged in the coming v4.4-rc1 merge window which alleviates this issue. For now, revert the two commits to restore per-process rwsem. They will be re-applied for the v4.4-rc1 merge window. Signed-off-by: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/g/55F8097A.7000206@de.ibm.com Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: stable@vger.kernel.org # v4.2+
2015-09-16genirq: Remove irq argument from irq flow handlersThomas Gleixner3-11/+11
Most interrupt flow handlers do not use the irq argument. Those few which use it can retrieve the irq number from the irq descriptor. Remove the argument. Search and replace was done with coccinelle and some extra helper scripts around it. Thanks to Julia for her help! Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Jiang Liu <jiang.liu@linux.intel.com>
2015-09-16genirq: Move field 'msi_desc' from irq_data into irq_common_dataJiang Liu2-5/+5
MSI descriptors are per-irq instead of per irqchip, so move it into struct irq_common_data. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: http://lkml.kernel.org/r/1433145945-789-35-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16genirq: Move field 'affinity' from irq_data into irq_common_dataJiang Liu1-6/+6
Irq affinity mask is per-irq instead of per irqchip, so move it into struct irq_common_data. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Link: http://lkml.kernel.org/r/1433303281-27688-1-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16genirq: Move field 'handler_data' from irq_data into irq_common_dataJiang Liu2-5/+5
Handler data (handler_data) is per-irq instead of per irqchip, so move it into struct irq_common_data. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: http://lkml.kernel.org/r/1433145945-789-13-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16genirq: Move field 'node' from irq_data into irq_common_dataJiang Liu1-3/+14
NUMA node information is per-irq instead of per-irqchip, so move it into struct irq_common_data. Also use CONFIG_NUMA to guard irq_common_data.node. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Link: http://lkml.kernel.org/r/1433145945-789-8-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16genirq: Provide IRQD_FORWARDED_TO_VCPU status flagThomas Gleixner1-0/+16
Provide a irq data flag to mark an irq forwarded to a VCPU along with the accessor functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2015-09-16genirq: Simplify irq_data_to_desc()Thomas Gleixner1-5/+1
Avoid the lookup of irq_desc and use the same mechanism for hierarchical and flat irqdomains. Based-on-a-patch-from: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16genirq: Remove __irq_set_handler_locked()Thomas Gleixner1-10/+0
All users converted to irq_set_handler_locked() Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16genirq: Remove __irq_set_chip_handler_name_locked()Thomas Gleixner1-13/+0
All users converted to irq_set_chip_handler_name_locked() Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16cpufreq: acpi-cpufreq: Use cpufreq_cpu_get_raw() in ->get()Rafael J. Wysocki1-0/+5
cpufreq_cpu_get() called by get_cur_freq_on_cpu() is overkill, because the ->get() callback is always invoked in a context in which all of the conditions checked by cpufreq_cpu_get() are guaranteed to be satisfied. Use cpufreq_cpu_get_raw() instead of it and drop the corresponding cpufreq_cpu_put() from get_cur_freq_on_cpu(). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-09-15genirq: Update the comment for generic_handle_irq_descHuang Shijie1-3/+1
__do_IRQ() was removed by commit 1c77ff2 "genirq: Remove __do_IRQ", but the comment referring to __do_IRQ() was left. Update the comment for generic_handle_irq_desc(). Signed-off-by: Huang Shijie <shijie.huang@arm.com> Cc: jiang.liu@linux.intel.com Cc: peterz@infradead.org Cc: rafael.j.wysocki@intel.com Cc: jason@lakedaemon.net Cc: marc.zyngier@arm.com Link: http://lkml.kernel.org/r/1441074950-3893-1-git-send-email-shijie.huang@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-15genirq: Remove stale commentThomas Gleixner1-4/+0
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-15locking/static_keys: Fix up the static keys documentationJonathan Corbet1-6/+4
Fix a few small mistakes in the static key documentation and delete an unneeded sentence. Suggested-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150914171105.511e1e21@lwn.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-15ACPI: Eliminate CONFIG_.*{, _MODULE} #ifdef in favor of IS_ENABLED()Sudeep Holla2-3/+3
This commit removes all CONFIG_.*{,_MODULE} in ACPI code, replacing it with IS_ENABLED(). Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-15Merge branch 'for-rafael' of ↵Rafael J. Wysocki1-1/+23
https://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq into pm-devfreq Pull devfreq updates for v4.3 from MyungJoo Ham. * 'for-rafael' of https://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq: PM / devfreq: Fix incorrect type issue. PM / devfreq: tegra: Update governor to use devfreq_update_stats() PM / devfreq: comments for get_dev_status usage updated PM / devfreq: drop comment about thermal setting max_freq PM / devfreq: cache the last call to get_dev_status() PM / devfreq: Drop unlikely before IS_ERR(_OR_NULL) PM / devfreq: exynos-ppmu: bit-wise operation bugfix. PM / devfreq: exynos-ppmu: Update documentation to support PPMUv2 PM / devfreq: exynos-ppmu: Add the support of PPMUv2 for Exynos5433 PM / devfreq: event: Remove incorrect property in exynos-ppmu DT binding Conflicts: drivers/devfreq/event/exynos-ppmu.c
2015-09-14clockevents: Remove unused set_mode() callbackViresh Kumar1-24/+5
All users are migrated to the per-state callbacks, get rid of the unused interface and the core support code. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linaro-kernel@lists.linaro.org Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/fd60de14cf6d125489c031207567bb255ad946f6.1441943991.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-12blk: rq_data_dir() should not return a booleanLinus Torvalds1-1/+1
rq_data_dir() returns either READ or WRITE (0 == READ, 1 == WRITE), not a boolean value. Now, admittedly the "!= 0" doesn't really change the value (0 stays as zero, 1 stays as one), but it's not only redundant, it confuses gcc, and causes gcc to warn about the construct switch (rq_data_dir(req)) { case READ: ... case WRITE: ... that we have in a few drivers. Now, the gcc warning is silly and stupid (it seems to warn not about the switch value having a different type from the case statements, but about _any_ boolean switch value), but in this case the code itself is silly and stupid too, so let's just change it, and get rid of warnings like this: drivers/block/hd.c: In function ‘hd_request’: drivers/block/hd.c:630:11: warning: switch condition has boolean value [-Wswitch-bool] switch (rq_data_dir(req)) { The odd '!= 0' came in when "cmd_flags" got turned into a "u64" in commit 5953316dbf90 ("block: make rq->cmd_flags be 64-bit") and is presumably because the old code (that just did a logical 'and' with 1) would then end up making the type of rq_data_dir() be u64 too. But if we want to retain the old regular integer type, let's just cast the result to 'int' rather than use that rather odd '!= 0'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-12Merge branch 'akpm' (patches from Andrew)Linus Torvalds5-10/+69
Merge fourth patch-bomb from Andrew Morton: - sys_membarier syscall - seq_file interface changes - a few misc fixups * emailed patches from Andrew Morton <akpm@linux-foundation.org>: revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each" mm/early_ioremap: add explicit #include of asm/early_ioremap.h fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void selftests: enhance membarrier syscall test selftests: add membarrier syscall test sys_membarrier(): system-wide memory barrier (generic, x86) MODSIGN: fix a compilation warning in extract-cert
2015-09-12Merge tag 'ntb-4.3' of git://github.com/jonmason/ntbLinus Torvalds2-5/+5
Pull NTB fixes from Jon Mason: "NTB bug and documentation fixes, new device IDs, performance improvements, and adding a mailing list to MAINTAINERS for NTB" * tag 'ntb-4.3' of git://github.com/jonmason/ntb: NTB: Fix range check on memory window index NTB: Improve index handling in B2B MW workaround NTB: Fix documentation for ntb_peer_db_clear. NTB: Fix documentation for ntb_link_is_up NTB: Use unique DMA channels for TX and RX NTB: Remove dma_sync_wait from ntb_async_rx NTB: Clean up QP stats info NTB: Make the transport list in order of discovery NTB: Add PCI Device IDs for Broadwell Xeon NTB: Add flow control to the ntb_netdev NTB: Add list to MAINTAINERS
2015-09-12Merge tag 'pm+acpi-4.3-rc1-2' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management and ACPI updates from Rafael Wysocki: "These are mostly fixes and cleanups on top of the previous PM+ACPI pull request (cpufreq core and drivers, cpuidle, generic power domains framework). Some of them didn't make to that pull request and some fix issues introduced by it. The only really new thing is the support for suspend frequency in the cpufreq-dt driver, but it is needed to fix an issue with Exynos platforms. Specifics: - build fix for the new Mediatek MT8173 cpufreq driver (Guenter Roeck). - generic power domains framework fixes (power on error code path, subdomain removal) and cleanup of a deprecated API user (Geert Uytterhoeven, Jon Hunter, Ulf Hansson). - cpufreq-dt driver fixes including two fixes for bugs related to the new Operating Performance Points Device Tree bindings introduced recently (Viresh Kumar). - suspend frequency support for the cpufreq-dt driver (Bartlomiej Zolnierkiewicz, Viresh Kumar). - cpufreq core cleanups (Viresh Kumar). - intel_pstate driver fixes (Chen Yu, Kristen Carlson Accardi). - additional sanity check in the cpuidle core (Xunlei Pang). - fix for a comment related to CPU power management (Lina Iyer)" * tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: intel_pstate: fix PCT_TO_HWP macro intel_pstate: Fix user input of min/max to legal policy region PM / OPP: Return suspend_opp only if it is enabled cpufreq-dt: add suspend frequency support cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency PM / OPP: add dev_pm_opp_get_suspend_opp() helper staging: board: Migrate away from __pm_genpd_name_add_device() cpufreq: Use __func__ to print function's name cpufreq: staticize cpufreq_cpu_get_raw() PM / Domains: Ensure subdomain is not in use before removing cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL cpuidle/coupled: Add sanity check for safe_state_index PM / Domains: Try power off masters in error path of __pm_genpd_poweron() cpufreq: dt: Tolerance applies on both sides of target voltage cpufreq: dt: Print error on failing to mark OPPs as shared cpufreq: dt: Check OPP count before marking them shared kernel/cpu_pm: fix cpu_cluster_pm_exit comment
2015-09-12Merge branch 'for-next' of ↵Linus Torvalds9-37/+40
git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending Pull SCSI target updates from Nicholas Bellinger: "Here are the outstanding target-pending updates for v4.3-rc1. Mostly bug-fixes and minor changes this round. The fallout from the big v4.2-rc1 RCU conversion have (thus far) been minimal. The highlights this round include: - Move sense handling routines into scsi_common code (Sagi) - Return ABORTED_COMMAND sense key for PI errors (Sagi) - Add tpg_enabled_sendtargets attribute for disabled iscsi-target discovery (David) - Shrink target struct se_cmd by rearranging fields (Roland) - Drop iSCSI use of mutex around max_cmd_sn increment (Roland) - Replace iSCSI __kernel_sockaddr_storage with sockaddr_storage (Andy + Chris) - Honor fabric max_data_sg_nents I/O transfer limit (Arun + Himanshu + nab) - Fix EXTENDED_COPY >= v4.1 regression OOPsen (Alex + nab)" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (37 commits) target: use stringify.h instead of own definition target/user: Fix UFLAG_UNKNOWN_OP handling target: Remove no-op conditional target/user: Remove unused variable target: Fix max_cmd_sn increment w/o cmdsn mutex regressions target: Attach EXTENDED_COPY local I/O descriptors to xcopy_pt_sess target/qla2xxx: Honor max_data_sg_nents I/O transfer limit target/iscsi: Replace __kernel_sockaddr_storage with sockaddr_storage target/iscsi: Replace conn->login_ip with login_sockaddr target/iscsi: Keep local_ip as the actual sockaddr target/iscsi: Fix np_ip bracket issue by removing np_ip target: Drop iSCSI use of mutex around max_cmd_sn increment qla2xxx: Update tcm_qla2xxx module description to 24xx+ iscsi-target: Add tpg_enabled_sendtargets for disabled discovery drivers: target: Drop unlikely before IS_ERR(_OR_NULL) target: check DPO/FUA usage for COMPARE AND WRITE target: Shrink struct se_cmd by rearranging fields target: Remove cmd->se_ordered_id (unused except debug log lines) target: add support for START_STOP_UNIT SCSI opcode target: improve unsupported opcode message ...
2015-09-12Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds2-35/+21
Pull second round of SCSI updates from James Bottomley: "There's one late arriving patch here (added today), fixing a build issue which the scsi_dh patch set in here uncovered. Other than that, everything has been incubated in -next and the checkers for a week. The major pieces of this patch are a set patches facilitating better integration between scsi and scsi_dh (the device handling layer used by multi-path; all the dm parts are acked by Mike Snitzer). This also includes driver updates for mp3sas, scsi_debug and an assortment of bug fixes" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (50 commits) scsi_dh: fix randconfig build error scsi: fix scsi_error_handler vs. scsi_host_dev_release race fcoe: Convert use of __constant_htons to htons mpt2sas: setpci reset kernel oops fix pm80xx: Don't override ts->stat on IO_OPEN_CNX_ERROR_HW_RESOURCE_BUSY lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2() bfa: Fix incorrect de-reference of pointer bfa: Fix indentation scsi_transport_sas: Remove check for SAS expander when querying bay/enclosure IDs. scsi_debug: resp_request: remove unused variable scsi_debug: fix REPORT LUNS Well Known LU scsi_debug: schedule_resp fix input variable check scsi_debug: make dump_sector static scsi_debug: vfree is null safe so drop the check scsi_debug: use SCSI_W_LUN_REPORT_LUNS instead of SAM2_WLUN_REPORT_LUNS; scsi_debug: define pr_fmt() for consistent logging mpt2sas: Refcount fw_events and fix unsafe list usage mpt2sas: Refcount sas_device objects and fix unsafe list usage scsi_dh: return SCSI_DH_NOTCONN in scsi_dh_activate() scsi_dh: don't allow to detach device handlers at runtime ...
2015-09-12Merge tag 'media/v4.3-2' of ↵Linus Torvalds2-6/+49
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media updates from Mauro Carvalho Chehab: "A series of patches that move part of the code used to allocate memory from the media subsystem to the mm subsystem" [ The mm parts have been acked by VM people, and the series was apparently in -mm for a while - Linus ] * tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: [media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames() [media] media: vb2: Remove unused functions [media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector [media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector [media] vb2: Provide helpers for mapping virtual addresses [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() [media] mm: Provide new get_vaddr_frames() helper [media] vb2: Push mmap_sem down to memops
2015-09-12Merge branch 'next' of ↵Linus Torvalds2-18/+14
git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux Pull thermal updates from Zhang Rui: - use int instead of unsigned long to represent temperature to avoid bogus overheat detection when negative temperature reported. From Sascha Hauer. - export available thermal governors information to user space via sysfs. From Wei Ni. - introduce new thermal driver for Wildcat Point platform controller hub, which uses PCH thermal sensor and associated critical and hot trip points. From Tushar Dave. - add suuport for Intel Skylake and Denlow platforms in powerclamp driver. - some small cleanups in thermal core. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: thermal: Add Intel PCH thermal driver thermal: Add comment explaining test for critical temperature thermal: Use IS_ENABLED instead of #ifdef thermal: remove unnecessary call to thermal_zone_device_set_polling thermal: trivial: fix typo in comment thermal: consistently use int for temperatures thermal: add available policies sysfs attribute thermal/powerclamp: add cpu id for denlow platform thermal/powerclamp: add cpu id for Skylake u/y thermal/powerclamp: add cpu id for skylake h/s
2015-09-12fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to voidJoe Perches1-9/+10
The seq_<foo> function return values were frequently misused. See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to seq_has_overflowed() and make public") All uses of these return values have been removed, so convert the return types to void. Miscellanea: o Move seq_put_decimal_<type> and seq_escape prototypes closer the other seq_vprintf prototypes o Reorder seq_putc and seq_puts to return early on overflow o Add argument names to seq_vprintf and seq_printf o Update the seq_escape kernel-doc o Convert a couple of leading spaces to tabs in seq_escape Signed-off-by: Joe Perches <joe@perches.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mark Brown <broonie@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joerg Roedel <jroedel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-12sys_membarrier(): system-wide memory barrier (generic, x86)Mathieu Desnoyers4-1/+59
Here is an implementation of a new system call, sys_membarrier(), which executes a memory barrier on all threads running on the system. It is implemented by calling synchronize_sched(). It can be used to distribute the cost of user-space memory barriers asymmetrically by transforming pairs of memory barriers into pairs consisting of sys_membarrier() and a compiler barrier. For synchronization primitives that distinguish between read-side and write-side (e.g. userspace RCU [1], rwlocks), the read-side can be accelerated significantly by moving the bulk of the memory barrier overhead to the write-side. The existing applications of which I am aware that would be improved by this system call are as follows: * Through Userspace RCU library (http://urcu.so) - DNS server (Knot DNS) https://www.knot-dns.cz/ - Network sniffer (http://netsniff-ng.org/) - Distributed object storage (https://sheepdog.github.io/sheepdog/) - User-space tracing (http://lttng.org) - Network storage system (https://www.gluster.org/) - Virtual routers (https://events.linuxfoundation.org/sites/events/files/slides/DPDK_RCU_0MQ.pdf) - Financial software (https://lkml.org/lkml/2015/3/23/189) Those projects use RCU in userspace to increase read-side speed and scalability compared to locking. Especially in the case of RCU used by libraries, sys_membarrier can speed up the read-side by moving the bulk of the memory barrier cost to synchronize_rcu(). * Direct users of sys_membarrier - core dotnet garbage collector (https://github.com/dotnet/coreclr/issues/198) Microsoft core dotnet GC developers are planning to use the mprotect() side-effect of issuing memory barriers through IPIs as a way to implement Windows FlushProcessWriteBuffers() on Linux. They are referring to sys_membarrier in their github thread, specifically stating that sys_membarrier() is what they are looking for. To explain the benefit of this scheme, let's introduce two example threads: Thread A (non-frequent, e.g. executing liburcu synchronize_rcu()) Thread B (frequent, e.g. executing liburcu rcu_read_lock()/rcu_read_unlock()) In a scheme where all smp_mb() in thread A are ordering memory accesses with respect to smp_mb() present in Thread B, we can change each smp_mb() within Thread A into calls to sys_membarrier() and each smp_mb() within Thread B into compiler barriers "barrier()". Before the change, we had, for each smp_mb() pairs: Thread A Thread B previous mem accesses previous mem accesses smp_mb() smp_mb() following mem accesses following mem accesses After the change, these pairs become: Thread A Thread B prev mem accesses prev mem accesses sys_membarrier() barrier() follow mem accesses follow mem accesses As we can see, there are two possible scenarios: either Thread B memory accesses do not happen concurrently with Thread A accesses (1), or they do (2). 1) Non-concurrent Thread A vs Thread B accesses: Thread A Thread B prev mem accesses sys_membarrier() follow mem accesses prev mem accesses barrier() follow mem accesses In this case, thread B accesses will be weakly ordered. This is OK, because at that point, thread A is not particularly interested in ordering them with respect to its own accesses. 2) Concurrent Thread A vs Thread B accesses Thread A Thread B prev mem accesses prev mem accesses sys_membarrier() barrier() follow mem accesses follow mem accesses In this case, thread B accesses, which are ensured to be in program order thanks to the compiler barrier, will be "upgraded" to full smp_mb() by synchronize_sched(). * Benchmarks On Intel Xeon E5405 (8 cores) (one thread is calling sys_membarrier, the other 7 threads are busy looping) 1000 non-expedited sys_membarrier calls in 33s =3D 33 milliseconds/call. * User-space user of this system call: Userspace RCU library Both the signal-based and the sys_membarrier userspace RCU schemes permit us to remove the memory barrier from the userspace RCU rcu_read_lock() and rcu_read_unlock() primitives, thus significantly accelerating them. These memory barriers are replaced by compiler barriers on the read-side, and all matching memory barriers on the write-side are turned into an invocation of a memory barrier on all active threads in the process. By letting the kernel perform this synchronization rather than dumbly sending a signal to every process threads (as we currently do), we diminish the number of unnecessary wake ups and only issue the memory barriers on active threads. Non-running threads do not need to execute such barrier anyway, because these are implied by the scheduler context switches. Results in liburcu: Operations in 10s, 6 readers, 2 writers: memory barriers in reader: 1701557485 reads, 2202847 writes signal-based scheme: 9830061167 reads, 6700 writes sys_membarrier: 9952759104 reads, 425 writes sys_membarrier (dyn. check): 7970328887 reads, 425 writes The dynamic sys_membarrier availability check adds some overhead to the read-side compared to the signal-based scheme, but besides that, sys_membarrier slightly outperforms the signal-based scheme. However, this non-expedited sys_membarrier implementation has a much slower grace period than signal and memory barrier schemes. Besides diminishing the number of wake-ups, one major advantage of the membarrier system call over the signal-based scheme is that it does not need to reserve a signal. This plays much more nicely with libraries, and with processes injected into for tracing purposes, for which we cannot expect that signals will be unused by the application. An expedited version of this system call can be added later on to speed up the grace period. Its implementation will likely depend on reading the cpu_curr()->mm without holding each CPU's rq lock. This patch adds the system call to x86 and to asm-generic. [1] http://urcu.so membarrier(2) man page: MEMBARRIER(2) Linux Programmer's Manual MEMBARRIER(2) NAME membarrier - issue memory barriers on a set of threads SYNOPSIS #include <linux/membarrier.h> int membarrier(int cmd, int flags); DESCRIPTION The cmd argument is one of the following: MEMBARRIER_CMD_QUERY Query the set of supported commands. It returns a bitmask of supported commands. MEMBARRIER_CMD_SHARED Execute a memory barrier on all threads running on the system. Upon return from system call, the caller thread is ensured that all running threads have passed through a state where all memory accesses to user-space addresses match program order between entry to and return from the system call (non-running threads are de facto in such a state). This covers threads from all pro=E2=80=90 cesses running on the system. This command returns 0. The flags argument needs to be 0. For future extensions. All memory accesses performed in program order from each targeted thread is guaranteed to be ordered with respect to sys_membarrier(). If we use the semantic "barrier()" to represent a compiler barrier forcing memory accesses to be performed in program order across the barrier, and smp_mb() to represent explicit memory barriers forcing full memory ordering across the barrier, we have the following ordering table for each pair of barrier(), sys_membarrier() and smp_mb(): The pair ordering is detailed as (O: ordered, X: not ordered): barrier() smp_mb() sys_membarrier() barrier() X X O smp_mb() X O O sys_membarrier() O O O RETURN VALUE On success, these system calls return zero. On error, -1 is returned, and errno is set appropriately. For a given command, with flags argument set to 0, this system call is guaranteed to always return the same value until reboot. ERRORS ENOSYS System call is not implemented. EINVAL Invalid arguments. Linux 2015-04-15 MEMBARRIER(2) Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nicholas Miell <nmiell@comcast.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Pranith Kumar <bobby.prani@gmail.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-11Merge branch 'for-linus' of ↵Linus Torvalds3-1/+9
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph update from Sage Weil: "There are a few fixes for snapshot behavior with CephFS and support for the new keepalive protocol from Zheng, a libceph fix that affects both RBD and CephFS, a few bug fixes and cleanups for RBD from Ilya, and several small fixes and cleanups from Jianpeng and others" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: improve readahead for file holes ceph: get inode size for each append write libceph: check data_len in ->alloc_msg() libceph: use keepalive2 to verify the mon session is alive rbd: plug rbd_dev->header.object_prefix memory leak rbd: fix double free on rbd_dev->header_name libceph: set 'exists' flag for newly up osd ceph: cleanup use of ceph_msg_get ceph: no need to get parent inode in ceph_open ceph: remove the useless judgement ceph: remove redundant test of head->safe and silence static analysis warnings ceph: fix queuing inode to mdsdir's snaprealm libceph: rename con_work() to ceph_con_workfn() libceph: Avoid holding the zero page on ceph_msgr_slab_init errors libceph: remove the unused macro AES_KEY_SIZE ceph: invalidate dirty pages after forced umount ceph: EIO all operations after forced umount
2015-09-11Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds1-1/+1
Pull drm fixes from Dave Airlie: "Just a bunch of fixes to squeeze in before -rc1: - three nouveau regression fixes - one qxl regression fix - a bunch of i915 fixes ... and some core displayport/atomic fixes" * 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: drm/nouveau/device: enable c800 quirk for tecra w50 drm/nouveau/clk/gt215: Unbreak engine pausing for GT21x/MCP7x drm/nouveau/gr/nv04: fix big endian setting on gr context drm/qxl: validate monitors config modes drm/i915: Allow DSI dual link to be configured on any pipe drm/i915: Don't try to use DDR DVFS on CHV when disabled in the BIOS drm/i915: Fix CSR MMIO address check drm/i915: Limit the number of loops for reading a split 64bit register drm/i915: Fix broken mst get_hw_state. drm/i915: Pass hpd_status_i915[] to intel_get_hpd_pins() in pre-g4x uapi/drm/i915_drm.h: fix userspace compilation. drm/i915: Always mark the object as dirty when used by the GPU drm/dp: Add dp_aux_i2c_speed_khz module param to set the assume i2c bus speed drm/dp: Adjust i2c-over-aux retry count based on message size and i2c bus speed drm/dp: Define AUX_RETRY_INTERVAL as 500 us drm/atomic: Fix bookkeeping with TEST_ONLY, v3.
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-17 02:34:17 +0300