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2011-07-25Merge branch 'for-3.1/core' of git://git.kernel.dk/linux-blockLinus Torvalds
* 'for-3.1/core' of git://git.kernel.dk/linux-block: (24 commits) block: strict rq_affinity backing-dev: use synchronize_rcu_expedited instead of synchronize_rcu block: fix patch import error in max_discard_sectors check block: reorder request_queue to remove 64 bit alignment padding CFQ: add think time check for group CFQ: add think time check for service tree CFQ: move think time check variables to a separate struct fixlet: Remove fs_excl from struct task. cfq: Remove special treatment for metadata rqs. block: document blk_plug list access block: avoid building too big plug list compat_ioctl: fix make headers_check regression block: eliminate potential for infinite loop in blkdev_issue_discard compat_ioctl: fix warning caused by qemu block: flush MEDIA_CHANGE from drivers on close(2) blk-throttle: Make total_nr_queued unsigned block: Add __attribute__((format(printf...) and fix fallout fs/partitions/check.c: make local symbols static block:remove some spare spaces in genhd.c block:fix the comment error in blkdev.h ...
2011-07-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linusLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: modpost: Fix modpost's license checking V3 module: add /sys/module/<name>/uevent files module: change attr callbacks to take struct module_kobject modules: make arch's use default loader hooks modules: add default loader hook implementations param: fix return value handling in param_set_*
2011-07-24Merge branch 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
* 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (143 commits) KVM: IOMMU: Disable device assignment without interrupt remapping KVM: MMU: trace mmio page fault KVM: MMU: mmio page fault support KVM: MMU: reorganize struct kvm_shadow_walk_iterator KVM: MMU: lockless walking shadow page table KVM: MMU: do not need atomicly to set/clear spte KVM: MMU: introduce the rules to modify shadow page table KVM: MMU: abstract some functions to handle fault pfn KVM: MMU: filter out the mmio pfn from the fault pfn KVM: MMU: remove bypass_guest_pf KVM: MMU: split kvm_mmu_free_page KVM: MMU: count used shadow pages on prepareing path KVM: MMU: rename 'pt_write' to 'emulate' KVM: MMU: cleanup for FNAME(fetch) KVM: MMU: optimize to handle dirty bit KVM: MMU: cache mmio info on page fault path KVM: x86: introduce vcpu_mmio_gva_to_gpa to cleanup the code KVM: MMU: do not update slot bitmap if spte is nonpresent KVM: MMU: fix walking shadow page table KVM guest: KVM Steal time registration ...
2011-07-24module: add /sys/module/<name>/uevent filesKay Sievers
Userspace wants to manage module parameters with udev rules. This currently only works for loaded modules, but not for built-in ones. To allow access to the built-in modules we need to re-trigger all module load events that happened before any userspace was running. We already do the same thing for all devices, subsystems(buses) and drivers. This adds the currently missing /sys/module/<name>/uevent files to all module entries. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (split & trivial fix)
2011-07-24module: change attr callbacks to take struct module_kobjectKay Sievers
This simplifies the next patch, where we have an attribute on a builtin module (ie. module == NULL). Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (split into 2)
2011-07-24modules: add default loader hook implementationsJonas Bonn
The module loader code allows architectures to hook into the code by providing a small number of entry points that each arch must implement. This patch provides __weakly linked generic implementations of these entry points for architectures that don't need to do anything special. Signed-off-by: Jonas Bonn <jonas@southpole.se> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-24param: fix return value handling in param_set_*Satoru Moriya
In STANDARD_PARAM_DEF, param_set_* handles the case in which strtolfn returns -EINVAL but it may return -ERANGE. If it returns -ERANGE, param_set_* may set uninitialized value to the paramerter. We should handle both cases. The one of the cases in which strtolfn() returns -ERANGE is following: *Type of module parameter is long *Set the parameter more than LONG_MAX Signed-off-by: Satoru Moriya <satoru.moriya@hds.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-23Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (107 commits) vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filp isofs: Remove global fs lock jffs2: fix IN_DELETE_SELF on overwriting rename() killing a directory fix IN_DELETE_SELF on overwriting rename() on ramfs et.al. mm/truncate.c: fix build for CONFIG_BLOCK not enabled fs:update the NOTE of the file_operations structure Remove dead code in dget_parent() AFS: Fix silly characters in a comment switch d_add_ci() to d_splice_alias() in "found negative" case as well simplify gfs2_lookup() jfs_lookup(): don't bother with . or .. get rid of useless dget_parent() in btrfs rename() and link() get rid of useless dget_parent() in fs/btrfs/ioctl.c fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers drivers: fix up various ->llseek() implementations fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek Ext4: handle SEEK_HOLE/SEEK_DATA generically Btrfs: implement our own ->llseek fs: add SEEK_HOLE and SEEK_DATA flags reiserfs: make reiserfs default to barrier=flush ... Fix up trivial conflicts in fs/xfs/linux-2.6/xfs_super.c due to the new shrinker callout for the inode cache, that clashed with the xfs code to start the periodic workers later.
2011-07-23Merge branch 'x86-mtrr-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, mtrr: Use pci_dev->revision x86, mtrr: use stop_machine APIs for doing MTRR rendezvous stop_machine: implement stop_machine_from_inactive_cpu() stop_machine: reorganize stop_cpus() implementation x86, mtrr: lock stop machine during MTRR rendezvous sequence
2011-07-22Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: time: Fix stupid KERN_WARN compile issue rtc: Avoid accumulating time drift in suspend/resume time: Avoid accumulating time drift in suspend/resume time: Catch invalid timespec sleep values in __timekeeping_inject_sleeptime
2011-07-22Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (24 commits) sched: Cleanup duplicate local variable in [enqueue|dequeue]_task_fair sched: Replace use of entity_key() sched: Separate group-scheduling code more clearly sched: Reorder root_domain to remove 64 bit alignment padding sched: Do not attempt to destroy uninitialized rt_bandwidth sched: Remove unused function cpu_cfs_rq() sched: Fix (harmless) typo 'CONFG_FAIR_GROUP_SCHED' sched, cgroup: Optimize load_balance_fair() sched: Don't update shares twice on on_rq parent sched: update correct entity's runtime in check_preempt_wakeup() xtensa: Use generic config PREEMPT definition h8300: Use generic config PREEMPT definition m32r: Use generic PREEMPT config sched: Skip autogroup when looking for all rt sched groups sched: Simplify mutex_spin_on_owner() sched: Remove rcu_read_lock() from wake_affine() sched: Generalize sleep inside spinlock detection sched: Make sleeping inside spinlock detection working in !CONFIG_PREEMPT sched: Isolate preempt counting in its own config option sched: Remove pointless in_atomic() definition check ...
2011-07-22Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (123 commits) perf: Remove the nmi parameter from the oprofile_perf backend x86, perf: Make copy_from_user_nmi() a library function perf: Remove perf_event_attr::type check x86, perf: P4 PMU - Fix typos in comments and style cleanup perf tools: Make test use the preset debugfs path perf tools: Add automated tests for events parsing perf tools: De-opt the parse_events function perf script: Fix display of IP address for non-callchain path perf tools: Fix endian conversion reading event attr from file header perf tools: Add missing 'node' alias to the hw_cache[] array perf probe: Support adding probes on offline kernel modules perf probe: Add probed module in front of function perf probe: Introduce debuginfo to encapsulate dwarf information perf-probe: Move dwarf library routines to dwarf-aux.{c, h} perf probe: Remove redundant dwarf functions perf probe: Move strtailcmp to string.c perf probe: Rename DIE_FIND_CB_FOUND to DIE_FIND_CB_END tracing/kprobe: Update symbol reference when loading module tracing/kprobes: Support module init function probing kprobes: Return -ENOENT if probe point doesn't exist ...
2011-07-22Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: Fix wrong check in list_splice_init_rcu() net,rcu: Convert call_rcu(xt_rateest_free_rcu) to kfree_rcu() sysctl,rcu: Convert call_rcu(free_head) to kfree vmalloc,rcu: Convert call_rcu(rcu_free_vb) to kfree_rcu() vmalloc,rcu: Convert call_rcu(rcu_free_va) to kfree_rcu() ipc,rcu: Convert call_rcu(ipc_immediate_free) to kfree_rcu() ipc,rcu: Convert call_rcu(free_un) to kfree_rcu() security,rcu: Convert call_rcu(sel_netport_free) to kfree_rcu() security,rcu: Convert call_rcu(sel_netnode_free) to kfree_rcu() ia64,rcu: Convert call_rcu(sn_irq_info_free) to kfree_rcu() block,rcu: Convert call_rcu(disk_free_ptbl_rcu_cb) to kfree_rcu() scsi,rcu: Convert call_rcu(fc_rport_free_rcu) to kfree_rcu() audit_tree,rcu: Convert call_rcu(__put_tree) to kfree_rcu() security,rcu: Convert call_rcu(whitelist_item_free) to kfree_rcu() md,rcu: Convert call_rcu(free_conf) to kfree_rcu()
2011-07-22Merge branch 'core-printk-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: Fix trace_[soft,hard]irqs_[on,off]() recursion printk: Fix console_sem vs logbuf_lock unlock race printk: Release console_sem after logbuf_lock
2011-07-22Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: Fix lockdep_no_validate against IRQ states mutex: Make mutex_destroy() an inline function plist: Remove the need to supply locks to plist heads lockup detector: Fix reference to the non-existent CONFIG_DETECT_SOFTLOCKUP option
2011-07-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: (51 commits) PM: Improve error code of pm_notifier_call_chain() PM: Add "RTC" to PM trace time stamps to avoid confusion PM / Suspend: Export suspend_set_ops, suspend_valid_only_mem PM / Suspend: Add .suspend_again() callback to suspend_ops PM / OPP: Introduce function to free cpufreq table ARM / shmobile: Return -EBUSY from A4LC power off if A3RV is active PM / Domains: Take .power_off() error code into account ARM / shmobile: Use genpd_queue_power_off_work() ARM / shmobile: Use pm_genpd_poweroff_unused() PM / Domains: Introduce function to power off all unused PM domains OMAP: PM: disable idle on suspend for GPIO and UART OMAP: PM: omap_device: add API to disable idle on suspend OMAP: PM: omap_device: add system PM methods for PM domain handling OMAP: PM: omap_device: conditionally use PM domain runtime helpers PM / Runtime: Add new helper function: pm_runtime_status_suspended() PM / Domains: Queue up power off work only if it is not pending PM / Domains: Improve handling of wakeup devices during system suspend PM / Domains: Do not restore all devices on power off error PM / Domains: Allow callbacks to execute all runtime PM helpers PM / Domains: Do not execute device callbacks under locks ...
2011-07-22Merge branch 'for-3.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
* 'for-3.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: separate out drain_workqueue() from destroy_workqueue() workqueue: remove cancel_rearming_delayed_work[queue]()
2011-07-22Merge branch 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/miscLinus Torvalds
* 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc: (39 commits) ptrace: do_wait(traced_leader_killed_by_mt_exec) can block forever ptrace: fix ptrace_signal() && STOP_DEQUEUED interaction connector: add an event for monitoring process tracers ptrace: dont send SIGSTOP on auto-attach if PT_SEIZED ptrace: mv send-SIGSTOP from do_fork() to ptrace_init_task() ptrace_init_task: initialize child->jobctl explicitly has_stopped_jobs: s/task_is_stopped/SIGNAL_STOP_STOPPED/ ptrace: make former thread ID available via PTRACE_GETEVENTMSG after PTRACE_EVENT_EXEC stop ptrace: wait_consider_task: s/same_thread_group/ptrace_reparented/ ptrace: kill real_parent_is_ptracer() in in favor of ptrace_reparented() ptrace: ptrace_reparented() should check same_thread_group() redefine thread_group_leader() as exit_signal >= 0 do not change dead_task->exit_signal kill task_detached() reparent_leader: check EXIT_DEAD instead of task_detached() make do_notify_parent() __must_check, update the callers __ptrace_detach: avoid task_detached(), check do_notify_parent() kill tracehook_notify_death() make do_notify_parent() return bool ptrace: s/tracehook_tracer_task()/ptrace_parent()/ ...
2011-07-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1287 commits) icmp: Fix regression in nexthop resolution during replies. net: Fix ppc64 BPF JIT dependencies. acenic: include NET_SKB_PAD headroom to incoming skbs ixgbe: convert to ndo_fix_features ixgbe: only enable WoL for magic packet by default ixgbe: remove ifdef check for non-existent define ixgbe: Pass staterr instead of re-reading status and error bits from descriptor ixgbe: Move interrupt related values out of ring and into q_vector ixgbe: add structure for containing RX/TX rings to q_vector ixgbe: inline the ixgbe_maybe_stop_tx function ixgbe: Update ATR to use recorded TX queues instead of CPU for routing igb: Fix for DH89xxCC near end loopback test e1000: always call e1000_check_for_link() on e1000_ce4100 MACs. netxen: add fw version compatibility check be2net: request native mode each time the card is reset ipv4: Constrain UFO fragment sizes to multiples of 8 bytes virtio_net: Fix panic in virtnet_remove ipv6: make fragment identifications less predictable ipv6: unshare inetpeers can: make function can_get_bittiming static ...
2011-07-22sched: Cleanup duplicate local variable in [enqueue|dequeue]_task_fairLin Ming
No need to define a new "cfs_rq" variable in the "for" block. Just use the one at the top of the function. Signed-off-by: Lin Ming <ming.m.lin@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1311297271.3938.1352.camel@minggr.sh.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/bluetooth/l2cap_core.c
2011-07-21Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
2011-07-21lockdep: Fix lockdep_no_validate against IRQ statesPeter Zijlstra
Thomas noticed that a lock marked with lockdep_set_novalidate_class() will still trigger warnings for IRQ inversions. Cure this by skipping those when marking irq state. Reported-and-tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-2dp5vmpsxeraqm42kgww6ge2@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21perf: Remove perf_event_attr::type checkLin Ming
PMU type id can be allocated dynamically, so perf_event_attr::type check when copying attribute from userspace to kernel is not valid. Signed-off-by: Lin Ming <ming.m.lin@intel.com> Cc: Robert Richter <robert.richter@amd.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1309421396-17438-4-git-send-email-ming.m.lin@intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Replace use of entity_key()Stephan Baerwolf
"entity_key()" is only used in "__enqueue_entity()" and its only function is to subtract a tasks vruntime by its groups minvruntime. Before this patch a rbtree enqueue-decision is done by comparing two tasks in the style: "if (entity_key(cfs_rq, se) < entity_key(cfs_rq, entry))" which would be "if (se->vruntime-cfs_rq->min_vruntime < entry->vruntime-cfs_rq->min_vruntime)" or (if reducing cfs_rq->min_vruntime out) "if (se->vruntime < entry->vruntime)" which is "if (entity_before(se, entry))" So we do not need "entity_key()". If "entity_before()" is inline we will also save one subtraction (only one, because "entity_key(cfs_rq, se)" was cached in "key") Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-ns12mnd2h5w8rb9agd8hnsfk@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Separate group-scheduling code more clearlyJan H. Schönherr
Clean up cfs/rt runqueue initialization by moving group scheduling related code into the corresponding functions. Also, keep group scheduling as an add-on, so that things are only done additionally, i. e. remove the init_*_rq() calls from init_tg_*_entry(). (This removes a redundant initalization during sched_init()). In case of group scheduling rt_rq->highest_prio.curr is now initialized twice, but adding another #ifdef seems not worth it. Signed-off-by: Jan H. Schönherr <schnhrr@cs.tu-berlin.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1310661163-16606-1-git-send-email-schnhrr@cs.tu-berlin.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Reorder root_domain to remove 64 bit alignment paddingRichard Kennedy
Reorder root_domain to remove 8 bytes of alignment padding on 64 bit builds, this shrinks the size from 1736 to 1728 bytes, therefore using one fewer cachelines. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1310726492.1977.5.camel@castor.rsk Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Do not attempt to destroy uninitialized rt_bandwidthBianca Lutz
If a task group is to be created and alloc_fair_sched_group() fails, then the rt_bandwidth of the corresponding task group is not yet initialized. The caller, sched_create_group(), starts a clean up procedure which calls free_rt_sched_group() which unconditionally destroys the not yet initialized rt_bandwidth. This crashes or hangs the system in lock_hrtimer_base(): UP systems dereference a NULL pointer, while SMP systems loop endlessly on a condition that cannot become true. This patch simply avoids the destruction of rt_bandwidth when the initialization code path was not reached. (This was discovered by accident with a custom kernel modification.) Signed-off-by: Bianca Lutz <sowilo@cs.tu-berlin.de> Signed-off-by: Jan Schoenherr <schnhrr@cs.tu-berlin.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1310580816-10861-7-git-send-email-schnhrr@cs.tu-berlin.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Remove unused function cpu_cfs_rq()Jan Schoenherr
The last reference to cpu_cfs_rq() was removed with commit 88ec22d3 ("sched: Remove the cfs_rq dependency from set_task_cpu()"). Thus, remove this function, too. Signed-off-by: Jan Schoenherr <schnhrr@cs.tu-berlin.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1310580816-10861-3-git-send-email-schnhrr@cs.tu-berlin.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Fix (harmless) typo 'CONFG_FAIR_GROUP_SCHED'Jan Schoenherr
This patch fixes a typo located in a comment. Signed-off-by: Jan Schoenherr <schnhrr@cs.tu-berlin.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1310580816-10861-2-git-send-email-schnhrr@cs.tu-berlin.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched, cgroup: Optimize load_balance_fair()Peter Zijlstra
Use for_each_leaf_cfs_rq() instead of list_for_each_entry_rcu(), this achieves that load_balance_fair() only iterates those task_groups that actually have tasks on busiest, and that we iterate bottom-up, trying to move light groups before the heavier ones. No idea if it will actually work out to be beneficial in practice, does anybody have a cgroup workload that might show a difference one way or the other? [ Also move update_h_load to sched_fair.c, loosing #ifdef-ery ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/1310557009.2586.28.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: Don't update shares twice on on_rq parentPaul Turner
In dequeue_task_fair() we bail on dequeue when we encounter a parenting entity with additional weight. However, we perform a double shares update on this entity as we continue the shares update traversal from this point, despite dequeue_entity() having already updated its queuing cfs_rq. Avoid this by starting from the parent when we resume. Signed-off-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110707053059.797714697@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21sched: update correct entity's runtime in check_preempt_wakeup()Paul Turner
While looking at check_preempt_wakeup() I realized that we are potentially updating the wrong entity in the fair-group scheduling case. In this case the current task's cfs_rq may not be the same as the one used for the comparison between the waking task and the existing task's vruntime. This potentially results in us using a stale vruntime in the pre-emption decision, providing a small false preference for the previous task. The effects of this are bounded since we always perform a hierarchal update on the tick. Signed-off-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/CAPM31R+2Ke2urUZKao5W92_LupdR4AYEv-EZWiJ3tG=tEes2cw@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21Merge branch 'linus' into sched/coreIngo Molnar
Merge reason: pick up the latest scheduler fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21ptrace: fix ptrace_signal() && STOP_DEQUEUED interactionOleg Nesterov
Simple test-case, int main(void) { int pid, status; pid = fork(); if (!pid) { pause(); assert(0); return 0x23; } assert(ptrace(PTRACE_ATTACH, pid, 0,0) == 0); assert(wait(&status) == pid); assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP); kill(pid, SIGCONT); // <--- also clears STOP_DEQUEUD assert(ptrace(PTRACE_CONT, pid, 0,0) == 0); assert(wait(&status) == pid); assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGCONT); assert(ptrace(PTRACE_CONT, pid, 0, SIGSTOP) == 0); assert(wait(&status) == pid); assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP); kill(pid, SIGKILL); return 0; } Without the patch it hangs. After the patch SIGSTOP "injected" by the tracer is not ignored and stops the tracee. Note also that if this test-case uses, say, SIGWINCH instead of SIGCONT, everything works without the patch. This can't be right, and this is confusing. The problem is that SIGSTOP (or any other sig_kernel_stop() signal) has no effect without JOBCTL_STOP_DEQUEUED. This means it is simply ignored after PTRACE_CONT unless JOBCTL_STOP_DEQUEUED was set "by accident", say it wasn't cleared after initial SIGSTOP sent by PTRACE_ATTACH. At first glance we could change ptrace_signal() to add STOP_DEQUEUED after return from ptrace_stop(), but this is not right in case when the tracer does not change the reported SIGSTOP and SIGCONT comes in between. This is even more wrong with PT_SEIZED, SIGCONT adds JOBCTL_TRAP_NOTIFY which will be "lost" during the TRAP_STOP | TRAP_NOTIFY report. So lets add STOP_DEQUEUED _before_ we report the signal. It has no effect unless sig_kernel_stop() == T after the tracer resumes us, and in the latter case the pending STOP_DEQUEUED means no SIGCONT in between, we should stop. Note also that if SIGCONT was sent, PT_SEIZED tracee will correctly report PTRACE_EVENT_STOP/SIGTRAP and thus the tracer can notice the fact SIGSTOP was cancelled. Also, move the current->ptrace check from ptrace_signal() to its caller, get_signal_to_deliver(), this looks more natural. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org>
2011-07-21Merge branch 'tip/perf/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core
2011-07-21Merge branch 'perf/urgent' into perf/coreIngo Molnar
Merge reason: pick up the latest fixes - they won't make v3.0. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-21rw_semaphore: remove up/down_read_non_ownerChristoph Hellwig
Now that the last users is gone these can be removed. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: signal: align __lock_task_sighand() irq disabling and RCU softirq,rcu: Inform RCU of irq_exit() activity sched: Add irq_{enter,exit}() to scheduler_ipi() rcu: protect __rcu_read_unlock() against scheduler-using irq handlers rcu: Streamline code produced by __rcu_read_unlock() rcu: Fix RCU_BOOST race handling current->rcu_read_unlock_special rcu: decrease rcu_report_exp_rnp coupling with scheduler
2011-07-20time: Fix stupid KERN_WARN compile issueJohn Stultz
Terribly embarassing. Don't know how I committed this, but its KERN_WARNING not KERN_WARN. This fixes the following compile error: kernel/time/timekeeping.c: In function ‘__timekeeping_inject_sleeptime’: kernel/time/timekeeping.c:608: error: ‘KERN_WARN’ undeclared (first use in this function) kernel/time/timekeeping.c:608: error: (Each undeclared identifier is reported only once kernel/time/timekeeping.c:608: error: for each function it appears in.) kernel/time/timekeeping.c:608: error: expected ‘)’ before string constant make[2]: *** [kernel/time/timekeeping.o] Error 1 Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-20sysctl,rcu: Convert call_rcu(free_head) to kfreePaul E. McKenney
The RCU callback free_head just calls kfree(), so we can use kfree_rcu() instead of call_rcu(). Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-07-20audit_tree,rcu: Convert call_rcu(__put_tree) to kfree_rcu()Lai Jiangshan
The rcu callback __put_tree() just calls a kfree(), so we use kfree_rcu() instead of the call_rcu(__put_tree). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Paris <eparis@redhat.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-07-20Merge branch 'rcu/urgent' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/urgent
2011-07-20signal: align __lock_task_sighand() irq disabling and RCUPaul E. McKenney
The __lock_task_sighand() function calls rcu_read_lock() with interrupts and preemption enabled, but later calls rcu_read_unlock() with interrupts disabled. It is therefore possible that this RCU read-side critical section will be preempted and later RCU priority boosted, which means that rcu_read_unlock() will call rt_mutex_unlock() in order to deboost itself, but with interrupts disabled. This results in lockdep splats, so this commit nests the RCU read-side critical section within the interrupt-disabled region of code. This prevents the RCU read-side critical section from being preempted, and thus prevents the attempt to deboost with interrupts disabled. It is quite possible that a better long-term fix is to make rt_mutex_unlock() disable irqs when acquiring the rt_mutex structure's ->wait_lock. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20softirq,rcu: Inform RCU of irq_exit() activityPeter Zijlstra
The rcu_read_unlock_special() function relies on in_irq() to exclude scheduler activity from interrupt level. This fails because exit_irq() can invoke the scheduler after clearing the preempt_count() bits that in_irq() uses to determine that it is at interrupt level. This situation can result in failures as follows: $task IRQ SoftIRQ rcu_read_lock() /* do stuff */ <preempt> |= UNLOCK_BLOCKED rcu_read_unlock() --t->rcu_read_lock_nesting irq_enter(); /* do stuff, don't use RCU */ irq_exit(); sub_preempt_count(IRQ_EXIT_OFFSET); invoke_softirq() ttwu(); spin_lock_irq(&pi->lock) rcu_read_lock(); /* do stuff */ rcu_read_unlock(); rcu_read_unlock_special() rcu_report_exp_rnp() ttwu() spin_lock_irq(&pi->lock) /* deadlock */ rcu_read_unlock_special(t); Ed can simply trigger this 'easy' because invoke_softirq() immediately does a ttwu() of ksoftirqd/# instead of doing the in-place softirq stuff first, but even without that the above happens. Cure this by also excluding softirqs from the rcu_read_unlock_special() handler and ensuring the force_irqthreads ksoftirqd/# wakeup is done from full softirq context. [ Alternatively, delaying the ->rcu_read_lock_nesting decrement until after the special handling would make the thing more robust in the face of interrupts as well. And there is a separate patch for that. ] Cc: Thomas Gleixner <tglx@linutronix.de> Reported-and-tested-by: Ed Tomlinson <edt@aei.ca> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20sched: Add irq_{enter,exit}() to scheduler_ipi()Peter Zijlstra
Ensure scheduler_ipi() calls irq_{enter,exit} when it does some actual work. Traditionally we never did any actual work from the resched IPI and all magic happened in the return from interrupt path. Now that we do do some work, we need to ensure irq_{enter,exit} are called so that we don't confuse things. This affects things like timekeeping, NO_HZ and RCU, basically everything with a hook in irq_enter/exit. Explicit examples of things going wrong are: sched_clock_cpu() -- has a callback when leaving NO_HZ state to take a new reading from GTOD and TSC. Without this callback, time is stuck in the past. RCU -- needs in_irq() to work in order to avoid some nasty deadlocks Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20rcu: protect __rcu_read_unlock() against scheduler-using irq handlersPaul E. McKenney
The addition of RCU read-side critical sections within runqueue and priority-inheritance lock critical sections introduced some deadlock cycles, for example, involving interrupts from __rcu_read_unlock() where the interrupt handlers call wake_up(). This situation can cause the instance of __rcu_read_unlock() invoked from interrupt to do some of the processing that would otherwise have been carried out by the task-level instance of __rcu_read_unlock(). When the interrupt-level instance of __rcu_read_unlock() is called with a scheduler lock held from interrupt-entry/exit situations where in_irq() returns false, deadlock can result. This commit resolves these deadlocks by using negative values of the per-task ->rcu_read_lock_nesting counter to indicate that an instance of __rcu_read_unlock() is in flight, which in turn prevents instances from interrupt handlers from doing any special processing. This patch is inspired by Steven Rostedt's earlier patch that similarly made __rcu_read_unlock() guard against interrupt-mediated recursion (see https://lkml.org/lkml/2011/7/15/326), but this commit refines Steven's approach to avoid the need for preemption disabling on the __rcu_read_unlock() fastpath and to also avoid the need for manipulating a separate per-CPU variable. This patch avoids need for preempt_disable() by instead using negative values of the per-task ->rcu_read_lock_nesting counter. Note that nested rcu_read_lock()/rcu_read_unlock() pairs are still permitted, but they will never see ->rcu_read_lock_nesting go to zero, and will therefore never invoke rcu_read_unlock_special(), thus preventing them from seeing the RCU_READ_UNLOCK_BLOCKED bit should it be set in ->rcu_read_unlock_special. This patch also adds a check for ->rcu_read_unlock_special being negative in rcu_check_callbacks(), thus preventing the RCU_READ_UNLOCK_NEED_QS bit from being set should a scheduling-clock interrupt occur while __rcu_read_unlock() is exiting from an outermost RCU read-side critical section. Of course, __rcu_read_unlock() can be preempted during the time that ->rcu_read_lock_nesting is negative. This could result in the setting of the RCU_READ_UNLOCK_BLOCKED bit after __rcu_read_unlock() checks it, and would also result it this task being queued on the corresponding rcu_node structure's blkd_tasks list. Therefore, some later RCU read-side critical section would enter rcu_read_unlock_special() to clean up -- which could result in deadlock if that critical section happened to be in the scheduler where the runqueue or priority-inheritance locks were held. This situation is dealt with by making rcu_preempt_note_context_switch() check for negative ->rcu_read_lock_nesting, thus refraining from queuing the task (and from setting RCU_READ_UNLOCK_BLOCKED) if we are already exiting from the outermost RCU read-side critical section (in other words, we really are no longer actually in that RCU read-side critical section). In addition, rcu_preempt_note_context_switch() invokes rcu_read_unlock_special() to carry out the cleanup in this case, which clears out the ->rcu_read_unlock_special bits and dequeues the task (if necessary), in turn avoiding needless delay of the current RCU grace period and needless RCU priority boosting. It is still illegal to call rcu_read_unlock() while holding a scheduler lock if the prior RCU read-side critical section has ever had either preemption or irqs enabled. However, the common use case is legal, namely where then entire RCU read-side critical section executes with irqs disabled, for example, when the scheduler lock is held across the entire lifetime of the RCU read-side critical section. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20sched: Avoid creating superfluous NUMA domains on non-NUMA systemsPeter Zijlstra
When creating sched_domains, stop when we've covered the entire target span instead of continuing to create domains, only to later find they're redundant and throw them away again. This avoids single node systems from touching funny NUMA sched_domain creation code and reduces the risks of the new SD_OVERLAP code. Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Anton Blanchard <anton@samba.org> Cc: mahesh@linux.vnet.ibm.com Cc: benh@kernel.crashing.org Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1311180177.29152.57.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-20sched: Allow for overlapping sched_domain spansPeter Zijlstra
Allow for sched_domain spans that overlap by giving such domains their own sched_group list instead of sharing the sched_groups amongst each-other. This is needed for machines with more than 16 nodes, because sched_domain_node_span() will generate a node mask from the 16 nearest nodes without regard if these masks have any overlap. Currently sched_domains have a sched_group that maps to their child sched_domain span, and since there is no overlap we share the sched_group between the sched_domains of the various CPUs. If however there is overlap, we would need to link the sched_group list in different ways for each cpu, and hence sharing isn't possible. In order to solve this, allocate private sched_groups for each CPU's sched_domain but have the sched_groups share a sched_group_power structure such that we can uniquely track the power. Reported-and-tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-08bxqw9wis3qti9u5inifh3y@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-20sched: Break out cpu_power from the sched_group structurePeter Zijlstra
In order to prepare for non-unique sched_groups per domain, we need to carry the cpu_power elsewhere, so put a level of indirection in. Reported-and-tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-qkho2byuhe4482fuknss40ad@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>