Commit Graph

22969 Commits

Author SHA1 Message Date
Linus Torvalds
468fc7ed55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Unified UDP encapsulation offload methods for drivers, from
    Alexander Duyck.

 2) Make DSA binding more sane, from Andrew Lunn.

 3) Support QCA9888 chips in ath10k, from Anilkumar Kolli.

 4) Several workqueue usage cleanups, from Bhaktipriya Shridhar.

 5) Add XDP (eXpress Data Path), essentially running BPF programs on RX
    packets as soon as the device sees them, with the option to mirror
    the packet on TX via the same interface.  From Brenden Blanco and
    others.

 6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet.

 7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli.

 8) Simplify netlink conntrack entry layout, from Florian Westphal.

 9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido
    Schimmel, Yotam Gigi, and Jiri Pirko.

10) Add SKB array infrastructure and convert tun and macvtap over to it.
    From Michael S Tsirkin and Jason Wang.

11) Support qdisc packet injection in pktgen, from John Fastabend.

12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy.

13) Add NV congestion control support to TCP, from Lawrence Brakmo.

14) Add GSO support to SCTP, from Marcelo Ricardo Leitner.

15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni.

16) Support MPLS over IPV4, from Simon Horman.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits)
  xgene: Fix build warning with ACPI disabled.
  be2net: perform temperature query in adapter regardless of its interface state
  l2tp: Correctly return -EBADF from pppol2tp_getname.
  net/mlx5_core/health: Remove deprecated create_singlethread_workqueue
  net: ipmr/ip6mr: update lastuse on entry change
  macsec: ensure rx_sa is set when validation is disabled
  tipc: dump monitor attributes
  tipc: add a function to get the bearer name
  tipc: get monitor threshold for the cluster
  tipc: make cluster size threshold for monitoring configurable
  tipc: introduce constants for tipc address validation
  net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update()
  MAINTAINERS: xgene: Add driver and documentation path
  Documentation: dtb: xgene: Add MDIO node
  dtb: xgene: Add MDIO node
  drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset
  drivers: net: xgene: Use exported functions
  drivers: net: xgene: Enable MDIO driver
  drivers: net: xgene: Add backward compatibility
  drivers: net: phy: xgene: Add MDIO driver
  ...
2016-07-27 12:03:20 -07:00
Linus Torvalds
08fd8c1768 xen: features and fixes for 4.8-rc0
- ACPI support for guests on ARM platforms.
 - Generic steal time support for arm and x86.
 - Support cases where kernel cpu is not Xen VCPU number (e.g., if
   in-guest kexec is used).
 - Use the system workqueue instead of a custom workqueue in various
   places.
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Merge tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Features and fixes for 4.8-rc0:

   - ACPI support for guests on ARM platforms.
   - Generic steal time support for arm and x86.
   - Support cases where kernel cpu is not Xen VCPU number (e.g., if
     in-guest kexec is used).
   - Use the system workqueue instead of a custom workqueue in various
     places"

* tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits)
  xen: add static initialization of steal_clock op to xen_time_ops
  xen/pvhvm: run xen_vcpu_setup() for the boot CPU
  xen/evtchn: use xen_vcpu_id mapping
  xen/events: fifo: use xen_vcpu_id mapping
  xen/events: use xen_vcpu_id mapping in events_base
  x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info
  x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op
  xen: introduce xen_vcpu_id mapping
  x86/acpi: store ACPI ids from MADT for future usage
  x86/xen: update cpuid.h from Xen-4.7
  xen/evtchn: add IOCTL_EVTCHN_RESTRICT
  xen-blkback: really don't leak mode property
  xen-blkback: constify instance of "struct attribute_group"
  xen-blkfront: prefer xenbus_scanf() over xenbus_gather()
  xen-blkback: prefer xenbus_scanf() over xenbus_gather()
  xen: support runqueue steal time on xen
  arm/xen: add support for vm_assist hypercall
  xen: update xen headers
  xen-pciback: drop superfluous variables
  xen-pciback: short-circuit read path used for merging write values
  ...
2016-07-27 11:35:37 -07:00
Oleg Nesterov
ce4f06dcbb stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE
Suppose that stop_machine(fn) hangs because fn() hangs. In this case NMI
hard-lockup can be triggered on another CPU which does nothing wrong and
the trace from nmi_panic() won't help to investigate the problem.

And this change "fixes" the problem we (seem to) hit in practice.

 - stop_two_cpus(0, 1) races with show_state_filter() running on CPU_0.

 - CPU_1 already spins in MULTI_STOP_PREPARE state, it detects the soft
   lockup and tries to report the problem.

 - show_state_filter() enables preemption, CPU_0 calls multi_cpu_stop()
   which goes to MULTI_STOP_DISABLE_IRQ state and disables interrupts.

 - CPU_1 spends more than 10 seconds trying to flush the log buffer to
   the slow serial console.

 - NMI interrupt on CPU_0 (which now waits for CPU_1) calls nmi_panic().

Reported-by: Wang Shu <shuwang@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20160726185736.GB4088@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-27 11:12:11 +02:00
Ben Hutchings
bca014caaa module: Invalidate signatures on force-loaded modules
Signing a module should only make it trusted by the specific kernel it
was built for, not anything else.  Loading a signed module meant for a
kernel with a different ABI could have interesting effects.
Therefore, treat all signatures as invalid when a module is
force-loaded.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-07-27 12:38:00 +09:30
Libor Pechacek
3205c36cf7 module: Issue warnings when tainting kernel
While most of the locations where a kernel taint bit is set are accompanied
with a warning message, there are two which set their bits silently.  If
the tainting module gets unloaded later on, it is almost impossible to tell
what was the reason for setting the flag.

Signed-off-by: Libor Pechacek <lpechacek@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-07-27 12:38:00 +09:30
Rusty Russell
c75b590d60 module: fix redundant test.
[linux-4.5-rc4/kernel/module.c:1692]: (style) Redundant condition: attr.test.
'!attr.test || (attr.test && attr.test(mod))' is equivalent to '!attr.test ||
attr.test(mod)'

This code was added like this ten years ago, in c988d2b284
"modules: add version and srcversion to sysfs".

Reported-by: David Binderman <dcb314@hotmail.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-07-27 12:38:00 +09:30
Jiri Kosina
bf262dcec6 module: fix noreturn attribute for __module_put_and_exit()
__module_put_and_exit() is makred noreturn in module.h declaration, but is
lacking the attribute in the definition, which makes some tools (such as
sparse) unhappy. Amend the definition with the attribute as well (and
reformat the declaration so that it uses more common format).

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-07-27 12:38:00 +09:30
Linus Torvalds
0e06f5c0de Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2

 - most(?) of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits)
  thp: fix comments of __pmd_trans_huge_lock()
  cgroup: remove unnecessary 0 check from css_from_id()
  cgroup: fix idr leak for the first cgroup root
  mm: memcontrol: fix documentation for compound parameter
  mm: memcontrol: remove BUG_ON in uncharge_list
  mm: fix build warnings in <linux/compaction.h>
  mm, thp: convert from optimistic swapin collapsing to conservative
  mm, thp: fix comment inconsistency for swapin readahead functions
  thp: update Documentation/{vm/transhuge,filesystems/proc}.txt
  shmem: split huge pages beyond i_size under memory pressure
  thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
  khugepaged: add support of collapse for tmpfs/shmem pages
  shmem: make shmem_inode_info::lock irq-safe
  khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page()
  thp: extract khugepaged from mm/huge_memory.c
  shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
  shmem: add huge pages support
  shmem: get_unmapped_area align huge page
  shmem: prepare huge= mount option and sysfs knob
  mm, rmap: account shmem thp pages
  ...
2016-07-26 19:55:54 -07:00
Linus Torvalds
6453dbdda3 Power management material for v4.8-rc1
- Rework the cpufreq governor interface to make it more straightforward
    and modify the conservative governor to avoid using transition
    notifications (Rafael Wysocki).
 
  - Rework the handling of frequency tables by the cpufreq core to make
    it more efficient (Viresh Kumar).
 
  - Modify the schedutil governor to reduce the number of wakeups it
    causes to occur in cases when the CPU frequency doesn't need to be
    changed (Steve Muckle, Viresh Kumar).
 
  - Fix some minor issues and clean up code in the cpufreq core and
    governors (Rafael Wysocki, Viresh Kumar).
 
  - Add Intel Broxton support to the intel_pstate driver (Srinivas
    Pandruvada).
 
  - Fix problems related to the config TDP feature and to the validity
    of the MSR_HWP_INTERRUPT register in intel_pstate (Jan Kiszka,
    Srinivas Pandruvada).
 
  - Make intel_pstate update the cpu_frequency tracepoint even if
    the frequency doesn't change to avoid confusing powertop (Rafael
    Wysocki).
 
  - Clean up the usage of __init/__initdata in intel_pstate, mark some
    of its internal variables as __read_mostly and drop an unused
    structure element from it (Jisheng Zhang, Carsten Emde).
 
  - Clean up the usage of some duplicate MSR symbols in intel_pstate
    and turbostat (Srinivas Pandruvada).
 
  - Update/fix the powernv, s3c24xx and mvebu cpufreq drivers (Akshay
    Adiga, Viresh Kumar, Ben Dooks).
 
  - Fix a regression (introduced during the 4.5 cycle) in the
    pcc-cpufreq driver by reverting the problematic commit (Andreas
    Herrmann).
 
  - Add support for Intel Denverton to intel_idle, clean up Broxton
    support in it and make it explicitly non-modular (Jacob Pan,
    Jan Beulich, Paul Gortmaker).
 
  - Add support for Denverton and Ivy Bridge server to the Intel RAPL
    power capping driver and make it more careful about the handing
    of MSRs that may not be present (Jacob Pan, Xiaolong Wang).
 
  - Fix resume from hibernation on x86-64 by making the CPU offline
    during resume avoid using MONITOR/MWAIT in the "play dead" loop
    which may lead to an inadvertent "revival" of a "dead" CPU and
    a page fault leading to a kernel crash from it (Rafael Wysocki).
 
  - Make memory management during resume from hibernation more
    straightforward (Rafael Wysocki).
 
  - Add debug features that should help to detect problems related
    to hibernation and resume from it (Rafael Wysocki, Chen Yu).
 
  - Clean up hibernation core somewhat (Rafael Wysocki).
 
  - Prevent KASAN from instrumenting the hibernation core which leads
    to large numbers of false-positives from it (James Morse).
 
  - Prevent PM (hibernate and suspend) notifiers from being called
    during the cleanup phase if they have not been called during the
    corresponding preparation phase which is possible if one of the
    other notifiers returns an error at that time (Lianwei Wang).
 
  - Improve suspend-related debug printout in the tasks freezer and
    clean up suspend-related console handling (Roger Lu, Borislav
    Petkov).
 
  - Update the AnalyzeSuspend script in the kernel sources to
    version 4.2 (Todd Brandt).
 
  - Modify the generic power domains framework to make it handle
    system suspend/resume better (Ulf Hansson).
 
  - Make the runtime PM framework avoid resuming devices synchronously
    when user space changes the runtime PM settings for them and
    improve its error reporting (Rafael Wysocki, Linus Walleij).
 
  - Fix error paths in devfreq drivers (exynos, exynos-ppmu, exynos-bus)
    and in the core, make some devfreq code explicitly non-modular and
    change some of it into tristate (Bartlomiej Zolnierkiewicz,
    Peter Chen, Paul Gortmaker).
 
  - Add DT support to the generic PM clocks management code and make
    it export some more symbols (Jon Hunter, Paul Gortmaker).
 
  - Make the PCI PM core code slightly more robust against possible
    driver errors (Andy Shevchenko).
 
  - Make it possible to change DESTDIR and PREFIX in turbostat
    (Andy Shevchenko).
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Merge tag 'pm-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael  Wysocki:
 "Again, the majority of changes go into the cpufreq subsystem, but
  there are no big features this time.  The cpufreq changes that stand
  out somewhat are the governor interface rework and improvements
  related to the handling of frequency tables.  Apart from those, there
  are fixes and new device/CPU IDs in drivers, cleanups and an
  improvement of the new schedutil governor.

  Next, there are some changes in the hibernation core, including a fix
  for a nasty problem related to the MONITOR/MWAIT usage by CPU offline
  during resume from hibernation, a few core improvements related to
  memory management during resume, a couple of additional debug features
  and cleanups.

  Finally, we have some fixes and cleanups in the devfreq subsystem,
  generic power domains framework improvements related to system
  suspend/resume, support for some new chips in intel_idle and in the
  power capping RAPL driver, a new version of the AnalyzeSuspend utility
  and some assorted fixes and cleanups.

  Specifics:

   - Rework the cpufreq governor interface to make it more
     straightforward and modify the conservative governor to avoid using
     transition notifications (Rafael Wysocki).

   - Rework the handling of frequency tables by the cpufreq core to make
     it more efficient (Viresh Kumar).

   - Modify the schedutil governor to reduce the number of wakeups it
     causes to occur in cases when the CPU frequency doesn't need to be
     changed (Steve Muckle, Viresh Kumar).

   - Fix some minor issues and clean up code in the cpufreq core and
     governors (Rafael Wysocki, Viresh Kumar).

   - Add Intel Broxton support to the intel_pstate driver (Srinivas
     Pandruvada).

   - Fix problems related to the config TDP feature and to the validity
     of the MSR_HWP_INTERRUPT register in intel_pstate (Jan Kiszka,
     Srinivas Pandruvada).

   - Make intel_pstate update the cpu_frequency tracepoint even if the
     frequency doesn't change to avoid confusing powertop (Rafael
     Wysocki).

   - Clean up the usage of __init/__initdata in intel_pstate, mark some
     of its internal variables as __read_mostly and drop an unused
     structure element from it (Jisheng Zhang, Carsten Emde).

   - Clean up the usage of some duplicate MSR symbols in intel_pstate
     and turbostat (Srinivas Pandruvada).

   - Update/fix the powernv, s3c24xx and mvebu cpufreq drivers (Akshay
     Adiga, Viresh Kumar, Ben Dooks).

   - Fix a regression (introduced during the 4.5 cycle) in the
     pcc-cpufreq driver by reverting the problematic commit (Andreas
     Herrmann).

   - Add support for Intel Denverton to intel_idle, clean up Broxton
     support in it and make it explicitly non-modular (Jacob Pan, Jan
     Beulich, Paul Gortmaker).

   - Add support for Denverton and Ivy Bridge server to the Intel RAPL
     power capping driver and make it more careful about the handing of
     MSRs that may not be present (Jacob Pan, Xiaolong Wang).

   - Fix resume from hibernation on x86-64 by making the CPU offline
     during resume avoid using MONITOR/MWAIT in the "play dead" loop
     which may lead to an inadvertent "revival" of a "dead" CPU and a
     page fault leading to a kernel crash from it (Rafael Wysocki).

   - Make memory management during resume from hibernation more
     straightforward (Rafael Wysocki).

   - Add debug features that should help to detect problems related to
     hibernation and resume from it (Rafael Wysocki, Chen Yu).

   - Clean up hibernation core somewhat (Rafael Wysocki).

   - Prevent KASAN from instrumenting the hibernation core which leads
     to large numbers of false-positives from it (James Morse).

   - Prevent PM (hibernate and suspend) notifiers from being called
     during the cleanup phase if they have not been called during the
     corresponding preparation phase which is possible if one of the
     other notifiers returns an error at that time (Lianwei Wang).

   - Improve suspend-related debug printout in the tasks freezer and
     clean up suspend-related console handling (Roger Lu, Borislav
     Petkov).

   - Update the AnalyzeSuspend script in the kernel sources to version
     4.2 (Todd Brandt).

   - Modify the generic power domains framework to make it handle system
     suspend/resume better (Ulf Hansson).

   - Make the runtime PM framework avoid resuming devices synchronously
     when user space changes the runtime PM settings for them and
     improve its error reporting (Rafael Wysocki, Linus Walleij).

   - Fix error paths in devfreq drivers (exynos, exynos-ppmu,
     exynos-bus) and in the core, make some devfreq code explicitly
     non-modular and change some of it into tristate (Bartlomiej
     Zolnierkiewicz, Peter Chen, Paul Gortmaker).

   - Add DT support to the generic PM clocks management code and make it
     export some more symbols (Jon Hunter, Paul Gortmaker).

   - Make the PCI PM core code slightly more robust against possible
     driver errors (Andy Shevchenko).

   - Make it possible to change DESTDIR and PREFIX in turbostat (Andy
     Shevchenko)"

* tag 'pm-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (89 commits)
  Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency"
  PM / hibernate: Introduce test_resume mode for hibernation
  cpufreq: export cpufreq_driver_resolve_freq()
  cpufreq: Disallow ->resolve_freq() for drivers providing ->target_index()
  PCI / PM: check all fields in pci_set_platform_pm()
  cpufreq: acpi-cpufreq: use cached frequency mapping when possible
  cpufreq: schedutil: map raw required frequency to driver frequency
  cpufreq: add cpufreq_driver_resolve_freq()
  cpufreq: intel_pstate: Check cpuid for MSR_HWP_INTERRUPT
  intel_pstate: Update cpu_frequency tracepoint every time
  cpufreq: intel_pstate: clean remnant struct element
  PM / tools: scripts: AnalyzeSuspend v4.2
  x86 / hibernate: Use hlt_play_dead() when resuming from hibernation
  cpufreq: powernv: Replacing pstate_id with frequency table index
  intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()
  PM / hibernate: Image data protection during restoration
  PM / hibernate: Add missing braces in __register_nosave_region()
  PM / hibernate: Clean up comments in snapshot.c
  PM / hibernate: Clean up function headers in snapshot.c
  PM / hibernate: Add missing braces in hibernate_setup()
  ...
2016-07-26 17:29:07 -07:00
Johannes Weiner
cb773df88a cgroup: remove unnecessary 0 check from css_from_id()
css_idr allocation starts at 1, so index 0 will never point to an item.
css_from_id() currently filters that before asking idr_find(), but
idr_find() would also just return NULL, so this is not needed.

Link: http://lkml.kernel.org/r/20160617162427.GC19084@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Johannes Weiner
1fe4d021ac cgroup: fix idr leak for the first cgroup root
The valid cgroup hierarchy ID range includes 0, so we can't filter for
positive numbers when freeing it, or it'll leak the first ID.  No big
deal, just disruptive when reading the code.

The ID is freed during error handling and when the reference count hits
zero, so the double-free test is not necessary; remove it.

Link: http://lkml.kernel.org/r/20160617162359.GB19084@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Vladimir Davydov
4949148ad4 mm: charge/uncharge kmemcg from generic page allocator paths
Currently, to charge a non-slab allocation to kmemcg one has to use
alloc_kmem_pages helper with __GFP_ACCOUNT flag.  A page allocated with
this helper should finally be freed using free_kmem_pages, otherwise it
won't be uncharged.

This API suits its current users fine, but it turns out to be impossible
to use along with page reference counting, i.e.  when an allocation is
supposed to be freed with put_page, as it is the case with pipe or unix
socket buffers.

To overcome this limitation, this patch moves charging/uncharging to
generic page allocator paths, i.e.  to __alloc_pages_nodemask and
free_pages_prepare, and zaps alloc/free_kmem_pages helpers.  This way,
one can use any of the available page allocation functions to get the
allocated page charged to kmemcg - it's enough to pass __GFP_ACCOUNT,
just like in case of kmalloc and friends.  A charged page will be
automatically uncharged on free.

To make it possible, we need to mark pages charged to kmemcg somehow.
To avoid introducing a new page flag, we make use of page->_mapcount for
marking such pages.  Since pages charged to kmemcg are not supposed to
be mapped to userspace, it should work just fine.  There are other
(ab)users of page->_mapcount - buddy and balloon pages - but we don't
conflict with them.

In case kmemcg is compiled out or not used at runtime, this patch
introduces no overhead to generic page allocator paths.  If kmemcg is
used, it will be plus one gfp flags check on alloc and plus one
page->_mapcount check on free, which shouldn't hurt performance, because
the data accessed are hot.

Link: http://lkml.kernel.org/r/a9736d856f895bcb465d9f257b54efe32eda6f99.1464079538.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Linus Torvalds
3fc9d69093 Merge branch 'for-4.8/drivers' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
 "This branch also contains core changes.  I've come to the conclusion
  that from 4.9 and forward, I'll be doing just a single branch.  We
  often have dependencies between core and drivers, and it's hard to
  always split them up appropriately without pulling core into drivers
  when that happens.

  That said, this contains:

   - separate secure erase type for the core block layer, from
     Christoph.

   - set of discard fixes, from Christoph.

   - bio shrinking fixes from Christoph, as a followup up to the
     op/flags change in the core branch.

   - map and append request fixes from Christoph.

   - NVMeF (NVMe over Fabrics) code from Christoph.  This is pretty
     exciting!

   - nvme-loop fixes from Arnd.

   - removal of ->driverfs_dev from Dan, after providing a
     device_add_disk() helper.

   - bcache fixes from Bhaktipriya and Yijing.

   - cdrom subchannel read fix from Vchannaiah.

   - set of lightnvm updates from Wenwei, Matias, Johannes, and Javier.

   - set of drbd updates and fixes from Fabian, Lars, and Philipp.

   - mg_disk error path fix from Bart.

   - user notification for failed device add for loop, from Minfei.

   - NVMe in general:
        + NVMe delay quirk from Guilherme.
        + SR-IOV support and command retry limits from Keith.
        + fix for memory-less NUMA node from Masayoshi.
        + use UINT_MAX for discard sectors, from Minfei.
        + cancel IO fixes from Ming.
        + don't allocate unused major, from Neil.
        + error code fixup from Dan.
        + use constants for PSDT/FUSE from James.
        + variable init fix from Jay.
        + fabrics fixes from Ming, Sagi, and Wei.
        + various fixes"

* 'for-4.8/drivers' of git://git.kernel.dk/linux-block: (115 commits)
  nvme/pci: Provide SR-IOV support
  nvme: initialize variable before logical OR'ing it
  block: unexport various bio mapping helpers
  scsi/osd: open code blk_make_request
  target: stop using blk_make_request
  block: simplify and export blk_rq_append_bio
  block: ensure bios return from blk_get_request are properly initialized
  virtio_blk: use blk_rq_map_kern
  memstick: don't allow REQ_TYPE_BLOCK_PC requests
  block: shrink bio size again
  block: simplify and cleanup bvec pool handling
  block: get rid of bio_rw and READA
  block: don't ignore -EOPNOTSUPP blkdev_issue_write_same
  block: introduce BLKDEV_DISCARD_ZERO to fix zeroout
  NVMe: don't allocate unused nvme_major
  nvme: avoid crashes when node 0 is memoryless node.
  nvme: Limit command retries
  loop: Make user notify for adding loop device failed
  nvme-loop: fix nvme-loop Kconfig dependencies
  nvmet: fix return value check in nvmet_subsys_alloc()
  ...
2016-07-26 15:37:51 -07:00
Linus Torvalds
d05d7f4079 Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:

   - the big change is the cleanup from Mike Christie, cleaning up our
     uses of command types and modified flags.  This is what will throw
     some merge conflicts

   - regression fix for the above for btrfs, from Vincent

   - following up to the above, better packing of struct request from
     Christoph

   - a 2038 fix for blktrace from Arnd

   - a few trivial/spelling fixes from Bart Van Assche

   - a front merge check fix from Damien, which could cause issues on
     SMR drives

   - Atari partition fix from Gabriel

   - convert cfq to highres timers, since jiffies isn't granular enough
     for some devices these days.  From Jan and Jeff

   - CFQ priority boost fix idle classes, from me

   - cleanup series from Ming, improving our bio/bvec iteration

   - a direct issue fix for blk-mq from Omar

   - fix for plug merging not involving the IO scheduler, like we do for
     other types of merges.  From Tahsin

   - expose DAX type internally and through sysfs.  From Toshi and Yigal

* 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits)
  block: Fix front merge check
  block: do not merge requests without consulting with io scheduler
  block: Fix spelling in a source code comment
  block: expose QUEUE_FLAG_DAX in sysfs
  block: add QUEUE_FLAG_DAX for devices to advertise their DAX support
  Btrfs: fix comparison in __btrfs_map_block()
  block: atari: Return early for unsupported sector size
  Doc: block: Fix a typo in queue-sysfs.txt
  cfq-iosched: Charge at least 1 jiffie instead of 1 ns
  cfq-iosched: Fix regression in bonnie++ rewrite performance
  cfq-iosched: Convert slice_resid from u64 to s64
  block: Convert fifo_time from ulong to u64
  blktrace: avoid using timespec
  block/blk-cgroup.c: Declare local symbols static
  block/bio-integrity.c: Add #include "blk.h"
  block/partition-generic.c: Remove a set-but-not-used variable
  block: bio: kill BIO_MAX_SIZE
  cfq-iosched: temporarily boost queue priority for idle classes
  block: drbd: avoid to use BIO_MAX_SIZE
  block: bio: remove BIO_MAX_SECTORS
  ...
2016-07-26 15:03:07 -07:00
Linus Torvalds
b55b048718 Merge branch 'for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "Nothing too exciting.

   - updates to the pids controller so that pid limit breaches can be
     noticed and monitored from userland.

   - cleanups and non-critical bug fixes"

* 'for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: remove duplicated include from cgroup.c
  cgroup: Use lld instead of ld when printing pids controller events_limit
  cgroup: Add pids controller event when fork fails because of pid limit
  cgroup: allow NULL return from ss->css_alloc()
  cgroup: remove unnecessary 0 check from css_from_id()
  cgroup: fix idr leak for the first cgroup root
2016-07-26 14:34:17 -07:00
Linus Torvalds
e65805251f Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The irq department delivers:

   - new core infrastructure to allow better management of multi-queue
     devices (interrupt spreading, node aware descriptor allocation ...)

   - a new interrupt flow handler to support the new fangled Intel VMD
     devices.

   - yet another new interrupt controller driver.

   - a series of fixes which addresses sparse warnings, missing
     includes, missing static declarations etc from Ben Dooks.

   - a fix for the error handling in the hierarchical domain allocation
     code.

   - the usual pile of small updates to core and driver code"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  genirq: Fix missing irq allocation affinity hint
  irqdomain: Fix irq_domain_alloc_irqs_recursive() error handling
  irq/Documentation: Correct result of echnoing 5 to smp_affinity
  MAINTAINERS: Remove Jiang Liu from irq domains
  genirq/msi: Fix broken debug output
  genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors
  genirq/msi: Make use of affinity aware allocations
  genirq: Use affinity hint in irqdesc allocation
  genirq: Add affinity hint to irq allocation
  genirq: Introduce IRQD_AFFINITY_MANAGED flag
  genirq/msi: Remove unused MSI_FLAG_IDENTITY_MAP
  irqchip/s3c24xx: Fixup IO accessors for big endian
  irqchip/exynos-combiner: Fix usage of __raw IO
  irqdomain: Fix disposal of mappings for interrupt hierarchies
  irqchip/aspeed-vic: Add irq controller for Aspeed
  doc/devicetree: Add Aspeed VIC bindings
  x86/PCI/VMD: Use untracked irq handler
  genirq: Add untracked irq handler
  irqchip/mips-gic: Populate irq_domain names
  irqchip/gicv3-its: Implement two-level(indirect) device table support
  ...
2016-07-25 21:35:03 -07:00
Linus Torvalds
55392c4c06 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "This update provides the following changes:

   - The rework of the timer wheel which addresses the shortcomings of
     the current wheel (cascading, slow search for next expiring timer,
     etc).  That's the first major change of the wheel in almost 20
     years since Finn implemted it.

   - A large overhaul of the clocksource drivers init functions to
     consolidate the Device Tree initialization

   - Some more Y2038 updates

   - A capability fix for timerfd

   - Yet another clock chip driver

   - The usual pile of updates, comment improvements all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (130 commits)
  tick/nohz: Optimize nohz idle enter
  clockevents: Make clockevents_subsys static
  clocksource/drivers/time-armada-370-xp: Fix return value check
  timers: Implement optimization for same expiry time in mod_timer()
  timers: Split out index calculation
  timers: Only wake softirq if necessary
  timers: Forward the wheel clock whenever possible
  timers/nohz: Remove pointless tick_nohz_kick_tick() function
  timers: Optimize collect_expired_timers() for NOHZ
  timers: Move __run_timers() function
  timers: Remove set_timer_slack() leftovers
  timers: Switch to a non-cascading wheel
  timers: Reduce the CPU index space to 256k
  timers: Give a few structs and members proper names
  hlist: Add hlist_is_singular_node() helper
  signals: Use hrtimer for sigtimedwait()
  timers: Remove the deprecated mod_timer_pinned() API
  timers, net/ipv4/inet: Initialize connection request timers as pinned
  timers, drivers/tty/mips_ejtag: Initialize the poll timer as pinned
  timers, drivers/tty/metag_da: Initialize the poll timer as pinned
  ...
2016-07-25 20:43:12 -07:00
Sargun Dhillon
96ae522795 bpf: Add bpf_probe_write_user BPF helper to be called in tracers
This allows user memory to be written to during the course of a kprobe.
It shouldn't be used to implement any kind of security mechanism
because of TOC-TOU attacks, but rather to debug, divert, and
manipulate execution of semi-cooperative processes.

Although it uses probe_kernel_write, we limit the address space
the probe can write into by checking the space with access_ok.
We do this as opposed to calling copy_to_user directly, in order
to avoid sleeping. In addition we ensure the threads's current fs
/ segment is USER_DS and the thread isn't exiting nor a kernel thread.

Given this feature is meant for experiments, and it has a risk of
crashing the system, and running programs, we print a warning on
when a proglet that attempts to use this helper is installed,
along with the pid and process name.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-25 18:07:48 -07:00
Linus Torvalds
77cd3d0c43 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes:

   - add initial commits to randomize kernel memory section virtual
     addresses, enabled via a new kernel option: RANDOMIZE_MEMORY
     (Thomas Garnier, Kees Cook, Baoquan He, Yinghai Lu)

   - enhance KASLR (RANDOMIZE_BASE) physical memory randomization (Kees
     Cook)

   - EBDA/BIOS region boot quirk cleanups (Andy Lutomirski, Ingo Molnar)

   - misc cleanups/fixes"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Simplify EBDA-vs-BIOS reservation logic
  x86/boot: Clarify what x86_legacy_features.reserve_bios_regions does
  x86/boot: Reorganize and clean up the BIOS area reservation code
  x86/mm: Do not reference phys addr beyond kernel
  x86/mm: Add memory hotplug support for KASLR memory randomization
  x86/mm: Enable KASLR for vmalloc memory regions
  x86/mm: Enable KASLR for physical mapping memory regions
  x86/mm: Implement ASLR for kernel memory regions
  x86/mm: Separate variable for trampoline PGD
  x86/mm: Add PUD VA support for physical mapping
  x86/mm: Update physical mapping variable names
  x86/mm: Refactor KASLR entropy functions
  x86/KASLR: Fix boot crash with certain memory configurations
  x86/boot/64: Add forgotten end of function marker
  x86/KASLR: Allow randomization below the load address
  x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G
  x86/KASLR: Randomize virtual address separately
  x86/KASLR: Clarify identity map interface
  x86/boot: Refuse to build with data relocations
  x86/KASLR, x86/power: Remove x86 hibernation restrictions
2016-07-25 17:32:28 -07:00
Linus Torvalds
766fd5f6cd Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull NOHZ updates from Ingo Molnar:

 - fix system/idle cputime leaked on cputime accounting (all nohz
   configs) (Rik van Riel)

 - remove the messy, ad-hoc irqtime account on nohz-full and make it
   compatible with CONFIG_IRQ_TIME_ACCOUNTING=y instead (Rik van Riel)

 - cleanups (Frederic Weisbecker)

 - remove unecessary irq disablement in the irqtime code (Rik van Riel)

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cputime: Drop local_irq_save/restore from irqtime_account_irq()
  sched/cputime: Reorganize vtime native irqtime accounting headers
  sched/cputime: Clean up the old vtime gen irqtime accounting completely
  sched/cputime: Replace VTIME_GEN irq time code with IRQ_TIME_ACCOUNTING code
  sched/cputime: Count actually elapsed irq & softirq time
2016-07-25 14:43:00 -07:00
Linus Torvalds
cca08cd66c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - introduce and use task_rcu_dereference()/try_get_task_struct() to fix
   and generalize task_struct handling (Oleg Nesterov)

 - do various per entity load tracking (PELT) fixes and optimizations
   (Peter Zijlstra)

 - cputime virt-steal time accounting enhancements/fixes (Wanpeng Li)

 - introduce consolidated cputime output file cpuacct.usage_all and
   related refactorings (Zhao Lei)

 - ... plus misc fixes and enhancements

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Panic on scheduling while atomic bugs if kernel.panic_on_warn is set
  sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together
  sched/cpuacct: Use loop to consolidate code in cpuacct_stats_show()
  sched/cpuacct: Merge cpuacct_usage_index and cpuacct_stat_index enums
  sched/fair: Rework throttle_count sync
  sched/core: Fix sched_getaffinity() return value kerneldoc comment
  sched/fair: Reorder cgroup creation code
  sched/fair: Apply more PELT fixes
  sched/fair: Fix PELT integrity for new tasks
  sched/cgroup: Fix cpu_cgroup_fork() handling
  sched/fair: Fix PELT integrity for new groups
  sched/fair: Fix and optimize the fork() path
  sched/cputime: Add steal time support to full dynticks CPU time accounting
  sched/cputime: Fix prev steal time accouting during CPU hotplug
  KVM: Fix steal clock warp during guest CPU hotplug
  sched/debug: Always show 'nr_migrations'
  sched/fair: Use task_rcu_dereference()
  sched/api: Introduce task_rcu_dereference() and try_get_task_struct()
  sched/idle: Optimize the generic idle loop
  sched/fair: Fix the wrong throttled clock time for cfs_rq_clock_task()
2016-07-25 13:59:34 -07:00
Linus Torvalds
7e4dc77b28 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "With over 300 commits it's been a busy cycle - with most of the work
  concentrated on the tooling side (as it should).

  The main kernel side enhancements were:

   - Add per event callchain limit: Recently we introduced a sysctl to
     tune the max-stack for all events for which callchains were
     requested:

       $ sysctl kernel.perf_event_max_stack
       kernel.perf_event_max_stack = 127

     Now this patch introduces a way to configure this per event, i.e.
     this becomes possible:

       $ perf record -e sched:*/max-stack=2/ -e block:*/max-stack=10/ -a

     allowing finer tuning of how much buffer space callchains use.

     This uses an u16 from the reserved space at the end, leaving
     another u16 for future use.

     There has been interest in even finer tuning, namely to control the
     max stack for kernel and userspace callchains separately.  Further
     discussion is needed, we may for instance use the remaining u16 for
     that and when it is present, assume that the sample_max_stack
     introduced in this patch applies for the kernel, and the u16 left
     is used for limiting the userspace callchain (Arnaldo Carvalho de
     Melo)

   - Optimize AUX event (hardware assisted side-band event) delivery
     (Kan Liang)

   - Rework Intel family name macro usage (this is partially x86 arch
     work) (Dave Hansen)

   - Refine and fix Intel LBR support (David Carrillo-Cisneros)

   - Add support for Intel 'TopDown' events (Andi Kleen)

   - Intel uncore PMU driver fixes and enhancements (Kan Liang)

   - ... other misc changes.

  Here's an incomplete list of the tooling enhancements (but there's
  much more, see the shortlog and the git log for details):

   - Support cross unwinding, i.e.  collecting '--call-graph dwarf'
     perf.data files in one machine and then doing analysis in another
     machine of a different hardware architecture.  This enables, for
     instance, to do:

       $ perf record -a --call-graph dwarf

     on a x86-32 or aarch64 system and then do 'perf report' on it on a
     x86_64 workstation (He Kuang)

   - Allow reading from a backward ring buffer (one setup via
     sys_perf_event_open() with perf_event_attr.write_backward = 1)
     (Wang Nan)

   - Finish merging initial SDT (Statically Defined Traces) support, see
     cset comments for details about how it all works (Masami Hiramatsu)

   - Support attaching eBPF programs to tracepoints (Wang Nan)

   - Add demangling of symbols in programs written in the Rust language
     (David Tolnay)

   - Add support for tracepoints in the python binding, including an
     example, that sets up and parses sched:sched_switch events,
     tools/perf/python/tracepoint.py (Jiri Olsa)

   - Introduce --stdio-color to set up the color output mode selection
     in 'annotate' and 'report', allowing emit color escape sequences
     when redirecting the output of these tools (Arnaldo Carvalho de
     Melo)

   - Add 'callindent' option to 'perf script -F', to indent the Intel PT
     call stack, making this output more ftrace-like (Adrian Hunter,
     Andi Kleen)

   - Allow dumping the object files generated by llvm when processing
     eBPF scriptlet events (Wang Nan)

   - Add stackcollapse.py script to help generating flame graphs (Paolo
     Bonzini)

   - Add --ldlat option to 'perf mem' to specify load latency for loads
     event (e.g. cpu/mem-loads/ ) (Jiri Olsa)

   - Tooling support for Intel TopDown counters, recently added to the
     kernel (Andi Kleen)"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (303 commits)
  perf tests: Add is_printable_array test
  perf tools: Make is_printable_array global
  perf script python: Fix string vs byte array resolving
  perf probe: Warn unmatched function filter correctly
  perf cpu_map: Add more helpers
  perf stat: Balance opening and reading events
  tools: Copy linux/{hash,poison}.h and check for drift
  perf tools: Remove include/linux/list.h from perf's MANIFEST
  tools: Copy the bitops files accessed from the kernel and check for drift
  Remove: kernel unistd*h files from perf's MANIFEST, not used
  perf tools: Remove tools/perf/util/include/linux/const.h
  perf tools: Remove tools/perf/util/include/asm/byteorder.h
  perf tools: Add missing linux/compiler.h include to perf-sys.h
  perf jit: Remove some no-op error handling
  perf jit: Add missing curly braces
  objtool: Initialize variable to silence old compiler
  objtool: Add -I$(srctree)/tools/arch/$(ARCH)/include/uapi
  perf record: Add --tail-synthesize option
  perf session: Don't warn about out of order event if write_backward is used
  perf tools: Enable overwrite settings
  ...
2016-07-25 13:20:41 -07:00
Linus Torvalds
c86ad14d30 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The locking tree was busier in this cycle than the usual pattern - a
  couple of major projects happened to coincide.

  The main changes are:

   - implement the atomic_fetch_{add,sub,and,or,xor}() API natively
     across all SMP architectures (Peter Zijlstra)

   - add atomic_fetch_{inc/dec}() as well, using the generic primitives
     (Davidlohr Bueso)

   - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
     Waiman Long)

   - optimize smp_cond_load_acquire() on arm64 and implement LSE based
     atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
     on arm64 (Will Deacon)

   - introduce smp_acquire__after_ctrl_dep() and fix various barrier
     mis-uses and bugs (Peter Zijlstra)

   - after discovering ancient spin_unlock_wait() barrier bugs in its
     implementation and usage, strengthen its semantics and update/fix
     usage sites (Peter Zijlstra)

   - optimize mutex_trylock() fastpath (Peter Zijlstra)

   - ... misc fixes and cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
  locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
  locking/static_keys: Fix non static symbol Sparse warning
  locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
  locking/atomic, arch/tile: Fix tilepro build
  locking/atomic, arch/m68k: Remove comment
  locking/atomic, arch/arc: Fix build
  locking/Documentation: Clarify limited control-dependency scope
  locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
  locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
  locking/atomic, arch/mips: Convert to _relaxed atomics
  locking/atomic, arch/alpha: Convert to _relaxed atomics
  locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
  locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
  locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
  locking/atomic: Fix atomic64_relaxed() bits
  locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  ...
2016-07-25 12:41:29 -07:00
Linus Torvalds
df00ccca72 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - documentation updates

   - miscellaneous fixes

   - minor reorganization of code

   - torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  rcu: Correctly handle sparse possible cpus
  rcu: sysctl: Panic on RCU Stall
  rcu: Fix a typo in a comment
  rcu: Make call_rcu_tasks() tolerate first call with irqs disabled
  rcu: Disable TASKS_RCU for usermode Linux
  rcu: No ordering for rcu_assign_pointer() of NULL
  rcutorture: Fix error return code in rcu_perf_init()
  torture: Inflict default jitter
  rcuperf: Don't treat gp_exp mis-setting as a WARN
  rcutorture: Drop "-soundhw pcspkr" from x86 boot arguments
  rcutorture: Don't specify the cpu type of QEMU on PPC
  rcutorture: Make -soundhw a x86 specific option
  rcutorture: Use vmlinux as the fallback kernel image
  rcutorture/doc: Create initrd using dracut
  torture: Stop onoff task if there is only one cpu
  torture: Add starvation events to error summary
  torture:  Break online and offline functions out of torture_onoff()
  torture: Forgive lengthy trace dumps and preemption
  torture: Remove CONFIG_RCU_TORTURE_TEST_RUNNABLE, simplify code
  torture: Simplify code, eliminate RCU_PERF_TEST_RUNNABLE
  ...
2016-07-25 12:04:11 -07:00
Daniel Borkmann
aa7145c16d bpf, events: fix offset in skb copy handler
This patch fixes the __output_custom() routine we currently use with
bpf_skb_copy(). I missed that when len is larger than the size of the
current handle, we can issue multiple invocations of copy_func, and
__output_custom() advances destination but also source buffer by the
written amount of bytes. When we have __output_custom(), this is actually
wrong since in that case the source buffer points to a non-linear object,
in our case an skb, which the copy_func helper is supposed to walk.
Therefore, since this is non-linear we thus need to pass the offset into
the helper, so that copy_func can use it for extracting the data from
the source object.

Therefore, adjust the callback signatures properly and pass offset
into the skb_header_pointer() invoked from bpf_skb_copy() callback. The
__DEFINE_OUTPUT_COPY_BODY() is adjusted to accommodate for two things:
i) to pass in whether we should advance source buffer or not; this is
a compile-time constant condition, ii) to pass in the offset for
__output_custom(), which we do with help of __VA_ARGS__, so everything
can stay inlined as is currently. Both changes allow for adapting the
__output_* fast-path helpers w/o extra overhead.

Fixes: 555c8a8623 ("bpf: avoid stack copy and use skb ctx for event output")
Fixes: 7e3f977edd ("perf, events: add non-linear data support for raw records")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-25 10:34:11 -07:00
Rafael J. Wysocki
9def970ead Merge branch 'pm-cpufreq'
* pm-cpufreq: (41 commits)
  Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency"
  cpufreq: export cpufreq_driver_resolve_freq()
  cpufreq: Disallow ->resolve_freq() for drivers providing ->target_index()
  cpufreq: acpi-cpufreq: use cached frequency mapping when possible
  cpufreq: schedutil: map raw required frequency to driver frequency
  cpufreq: add cpufreq_driver_resolve_freq()
  cpufreq: intel_pstate: Check cpuid for MSR_HWP_INTERRUPT
  intel_pstate: Update cpu_frequency tracepoint every time
  cpufreq: intel_pstate: clean remnant struct element
  cpufreq: powernv: Replacing pstate_id with frequency table index
  intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()
  cpufreq: Reuse new freq-table helpers
  cpufreq: Handle sorted frequency tables more efficiently
  cpufreq: Drop redundant check from cpufreq_update_current_freq()
  intel_pstate: Declare pid_params/pstate_funcs/hwp_active __read_mostly
  intel_pstate: add __init/__initdata marker to some functions/variables
  intel_pstate: Fix incorrect placement of __initdata
  cpufreq: mvebu: fix integer to pointer cast
  cpufreq: intel_pstate: Broxton support
  cpufreq: conservative: Do not use transition notifications
  ...
2016-07-25 13:46:08 +02:00
Rafael J. Wysocki
7f234a4d8a Merge branches 'pm-sleep' and 'pm-tools'
* pm-sleep:
  PM / hibernate: Introduce test_resume mode for hibernation
  x86 / hibernate: Use hlt_play_dead() when resuming from hibernation
  PM / hibernate: Image data protection during restoration
  PM / hibernate: Add missing braces in __register_nosave_region()
  PM / hibernate: Clean up comments in snapshot.c
  PM / hibernate: Clean up function headers in snapshot.c
  PM / hibernate: Add missing braces in hibernate_setup()
  PM / hibernate: Recycle safe pages after image restoration
  PM / hibernate: Simplify mark_unsafe_pages()
  PM / hibernate: Do not free preallocated safe pages during image restore
  PM / suspend: show workqueue state in suspend flow
  PM / sleep: make PM notifiers called symmetrically
  PM / sleep: Make pm_prepare_console() return void
  PM / Hibernate: Don't let kasan instrument snapshot.c

* pm-tools:
  PM / tools: scripts: AnalyzeSuspend v4.2
  tools/turbostat: allow user to alter DESTDIR and PREFIX
2016-07-25 13:44:32 +02:00
Linus Torvalds
25a0dc4be8 Staging / IIO driver update for 4.8-rc1
Here is the big Staging and IIO driver update for 4.8-rc1.
 
 We ended up adding more code than removing, again, but it's not all that
 bad.  Lots of cleanups all over the staging tree, and new IIO drivers,
 full details in the shortlog.
 
 All of these have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO driver updates from Greg KH:
 "Here is the big Staging and IIO driver update for 4.8-rc1.

  We ended up adding more code than removing, again, but it's not all
  that bad.  Lots of cleanups all over the staging tree, and new IIO
  drivers, full details in the shortlog.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (417 commits)
  drivers:iio:accel:mma8452: removed unwanted return statements
  drivers:iio:accel:mma8452: added cleanup provision in case of failure.
  iio: Add iio.git tree to MAINTAINERS
  iio:st_pressure: clean useless static channel initializers
  iio:st_pressure:lps22hb: temperature support
  iio:st_pressure:lps22hb: open drain support
  iio:st_pressure: temperature triggered buffering
  iio:st_pressure: document sampling gains
  iio:st_pressure: align storagebits on power of 2
  iio:st_sensors: align on storagebits boundaries
  staging:iio:lis3l02dq drop separate driver
  iio: accel: st_accel: Add lis3l02dq support
  iio: adc: add missing of_node references to iio_dev
  iio: adc: ti-ads1015: add indio_dev->dev.of_node reference
  iio: potentiometer: Fix typo in Kconfig
  iio: potentiometer: mcp4531: Add device tree binding
  iio: potentiometer: mcp4531: Add device tree binding documentation
  iio: potentiometer: mcp4531: Add support for MCP454x, MCP456x, MCP464x and MCP466x
  iio:imu:mpu6050: icm20608 initial support
  iio: adc: max1363: Add device tree binding
  ...
2016-07-24 16:55:23 -07:00
Dan Williams
0606263f24 Merge branch 'for-4.8/libnvdimm' into libnvdimm-for-next 2016-07-24 08:05:44 -07:00
David S. Miller
de0ba9a0d8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Just several instances of overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-24 00:53:32 -04:00
Chen Yu
fe12c00d21 PM / hibernate: Introduce test_resume mode for hibernation
test_resume mode is to verify if the snapshot data
written to swap device can be successfully restored
to memory. It is useful to ease the debugging process
on hibernation, since this mode can not only bypass
the BIOSes/bootloader, but also the system re-initialization.

To avoid the risk to break the filesystm on persistent storage,
this patch resumes the image with tasks frozen.

For example:
echo test_resume > /sys/power/disk
echo disk > /sys/power/state

[  187.306470] PM: Image saving progress:  70%
[  187.395298] PM: Image saving progress:  80%
[  187.476697] PM: Image saving progress:  90%
[  187.554641] PM: Image saving done.
[  187.558896] PM: Wrote 594600 kbytes in 0.90 seconds (660.66 MB/s)
[  187.566000] PM: S|
[  187.589742] PM: Basic memory bitmaps freed
[  187.594694] PM: Checking hibernation image
[  187.599865] PM: Image signature found, resuming
[  187.605209] PM: Loading hibernation image.
[  187.665753] PM: Basic memory bitmaps created
[  187.691397] PM: Using 3 thread(s) for decompression.
[  187.691397] PM: Loading and decompressing image data (148650 pages)...
[  187.889719] PM: Image loading progress:   0%
[  188.100452] PM: Image loading progress:  10%
[  188.244781] PM: Image loading progress:  20%
[  189.057305] PM: Image loading done.
[  189.068793] PM: Image successfully loaded

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-22 13:57:23 +02:00
Steve Muckle
5cbea46984 cpufreq: schedutil: map raw required frequency to driver frequency
The slow-path frequency transition path is relatively expensive as it
requires waking up a thread to do work. Should support be added for
remote CPU cpufreq updates that is also expensive since it requires an
IPI. These activities should be avoided if they are not necessary.

To that end, calculate the actual driver-supported frequency required by
the new utilization value in schedutil by using the recently added
cpufreq_driver_resolve_freq API. If it is the same as the previously
requested driver frequency then there is no need to continue with the
update assuming the cpu frequency limits have not changed. This will
have additional benefits should the semantics of the rate limit be
changed to apply solely to frequency transitions rather than to
frequency calculations in schedutil.

The last raw required frequency is cached. This allows the driver
frequency lookup to be skipped in the event that the new raw required
frequency matches the last one, assuming a frequency update has not been
forced due to limits changing (indicated by a next_freq value of
UINT_MAX, see sugov_should_update_freq).

Signed-off-by: Steve Muckle <smuckle@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-21 22:28:21 +02:00
Paul Moore
43761473c2 audit: fix a double fetch in audit_log_single_execve_arg()
There is a double fetch problem in audit_log_single_execve_arg()
where we first check the execve(2) argumnets for any "bad" characters
which would require hex encoding and then re-fetch the arguments for
logging in the audit record[1].  Of course this leaves a window of
opportunity for an unsavory application to munge with the data.

This patch reworks things by only fetching the argument data once[2]
into a buffer where it is scanned and logged into the audit
records(s).  In addition to fixing the double fetch, this patch
improves on the original code in a few other ways: better handling
of large arguments which require encoding, stricter record length
checking, and some performance improvements (completely unverified,
but we got rid of some strlen() calls, that's got to be a good
thing).

As part of the development of this patch, I've also created a basic
regression test for the audit-testsuite, the test can be tracked on
GitHub at the following link:

 * https://github.com/linux-audit/audit-testsuite/issues/25

[1] If you pay careful attention, there is actually a triple fetch
problem due to a strnlen_user() call at the top of the function.

[2] This is a tiny white lie, we do make a call to strnlen_user()
prior to fetching the argument data.  I don't like it, but due to the
way the audit record is structured we really have no choice unless we
copy the entire argument at once (which would require a rather
wasteful allocation).  The good news is that with this patch the
kernel no longer relies on this strnlen_user() value for anything
beyond recording it in the log, we also update it with a trustworthy
value whenever possible.

Reported-by: Pengfei Wang <wpengfeinudt@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-07-20 14:15:46 -04:00
Brenden Blanco
4acf6c0b84 bpf: enable direct packet data write for xdp progs
For forwarding to be effective, XDP programs should be allowed to
rewrite packet data.

This requires that the drivers supporting XDP must all map the packet
memory as TODEVICE or BIDIRECTIONAL before invoking the program.

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19 21:46:33 -07:00
Brenden Blanco
6a773a15a1 bpf: add XDP prog type for early driver filter
Add a new bpf prog type that is intended to run in early stages of the
packet rx path. Only minimal packet metadata will be available, hence a
new context type, struct xdp_md, is exposed to userspace. So far only
expose the packet start and end pointers, and only in read mode.

An XDP program must return one of the well known enum values, all other
return codes are reserved for future use. Unfortunately, this
restriction is hard to enforce at verification time, so take the
approach of warning at runtime when such programs are encountered. Out
of bounds return codes should alias to XDP_ABORTED.

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19 21:46:31 -07:00
Brenden Blanco
59d3656d5b bpf: add bpf_prog_add api for bulk prog refcnt
A subsystem may need to store many copies of a bpf program, each
deserving its own reference. Rather than requiring the caller to loop
one by one (with possible mid-loop failure), add a bulk bpf_prog_add
api.

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19 21:46:31 -07:00
Andrew Morton
183fc1537e kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug
kernel/trace/bpf_trace.c: In function 'bpf_event_output':
kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in initializer
kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
kernel/trace/bpf_trace.c:312: warning: (near initialization for 'raw.frag.<anonymous>')

Fixes: 555c8a8623 ("bpf: avoid stack copy and use skb ctx for event output")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19 19:27:01 -07:00
Wei Yongjun
55094f5753 cgroup: remove duplicated include from cgroup.c
Remove duplicated include.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-19 14:28:04 -04:00
Gaurav Jindal
1f3b0f8243 tick/nohz: Optimize nohz idle enter
tick_nohz_start_idle is called before checking whether the idle tick can be
stopped. If the tick cannot be stopped, calling tick_nohz_start_idle() is
pointless and just wasting CPU cycles.

Only invoke tick_nohz_start_idle() when can_stop_idle_tick() returns true. A
short one minute observation of the effect on ARM64 shows a reduction of calls
by 1.5% thus optimizing the idle entry sequence.

[tglx: Massaged changelog ]

Co-developed-by: Sanjeev Yadav<sanjeev.yadav@spreadtrum.com>
Signed-off-by: Gaurav Jindal<gaurav.jindal@spreadtrum.com>
Link: http://lkml.kernel.org/r/20160714120416.GB21099@gaurav.jindal@spreadtrum.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-19 13:48:24 +02:00
Vincent Stehle
eb0dc47ab6 genirq: Fix missing irq allocation affinity hint
The new affinity hint argument of __irq_domain_alloc_irqs() is missing in
irq_reserve_ipi(). Add it.

This fixes the following compilation error:

  kernel/irq/ipi.c: In function ‘irq_reserve_ipi’:
  kernel/irq/ipi.c:85:9: error: too few arguments to function ‘__irq_domain_alloc_irqs’
    virq = __irq_domain_alloc_irqs(domain, virq, nr_irqs, NUMA_NO_NODE,
           ^
Fixes: 06ee6d571f ("genirq: Add affinity hint to irq allocation")
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: linux-pci@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-19 10:49:47 +02:00
Ben Dooks
775be50626 clockevents: Make clockevents_subsys static
The clockevents_subsys struct is used for sysfs support and
is not declared or used outside the file it is defined in.
Fix the following warning by making it static:

kernel/time/clockevents.c:648:17: warning: symbol 'clockevents_subsys' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: linux-kernel@lists.codethink.co.uk
Link: http://lkml.kernel.org/r/1466178974-7105-1-git-send-email-ben.dooks@codethink.co.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-19 10:48:06 +02:00
Daniel Borkmann
858d68f102 bpf: bpf_event_entry_gen's alloc needs to be in atomic context
Should have been obvious, only called from bpf() syscall via map_update_elem()
that calls bpf_fd_array_map_update_elem() under RCU read lock and thus this
must also be in GFP_ATOMIC, of course.

Fixes: 3b1efb196e ("bpf, maps: flush own entries on perf map release")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-16 22:03:39 -07:00
Linus Torvalds
8dcf5a80dd Merge branch 'for-4.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fix from Tejun Heo:
 "The optimization for setting unbound worker affinity masks collided
  with recent scheduler changes triggering warning messages.

  This late pull request fixes the bug by removing the optimization"

* 'for-4.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Fix setting affinity of unbound worker threads
2016-07-16 06:36:55 +09:00
Daniel Borkmann
555c8a8623 bpf: avoid stack copy and use skb ctx for event output
This work addresses a couple of issues bpf_skb_event_output()
helper currently has: i) We need two copies instead of just a
single one for the skb data when it should be part of a sample.
The data can be non-linear and thus needs to be extracted via
bpf_skb_load_bytes() helper first, and then copied once again
into the ring buffer slot. ii) Since bpf_skb_load_bytes()
currently needs to be used first, the helper needs to see a
constant size on the passed stack buffer to make sure BPF
verifier can do sanity checks on it during verification time.
Thus, just passing skb->len (or any other non-constant value)
wouldn't work, but changing bpf_skb_load_bytes() is also not
the proper solution, since the two copies are generally still
needed. iii) bpf_skb_load_bytes() is just for rather small
buffers like headers, since they need to sit on the limited
BPF stack anyway. Instead of working around in bpf_skb_load_bytes(),
this work improves the bpf_skb_event_output() helper to address
all 3 at once.

We can make use of the passed in skb context that we have in
the helper anyway, and use some of the reserved flag bits as
a length argument. The helper will use the new __output_custom()
facility from perf side with bpf_skb_copy() as callback helper
to walk and extract the data. It will pass the data for setup
to bpf_event_output(), which generates and pushes the raw record
with an additional frag part. The linear data used in the first
frag of the record serves as programmatically defined meta data
passed along with the appended sample.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15 14:23:56 -07:00
Daniel Borkmann
8e7a3920ac bpf, perf: split bpf_perf_event_output
Split the bpf_perf_event_output() helper as a preparation into
two parts. The new bpf_perf_event_output() will prepare the raw
record itself and test for unknown flags from BPF trace context,
where the __bpf_perf_event_output() does the core work. The
latter will be reused later on from bpf_event_output() directly.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15 14:23:56 -07:00
Daniel Borkmann
7e3f977edd perf, events: add non-linear data support for raw records
This patch adds support for non-linear data on raw records. It
extends raw records to have one or multiple fragments that will
be written linearly into the ring slot, where each fragment can
optionally have a custom callback handler to walk and extract
complex, possibly non-linear data.

If a callback handler is provided for a fragment, then the new
__output_custom() will be used instead of __output_copy() for
the perf_output_sample() part. perf_prepare_sample() does all
the size calculation only once, so perf_output_sample() doesn't
need to redo the same work anymore, meaning real_size and padding
will be cached in the raw record. The raw record becomes 32 bytes
in size without holes; to not increase it further and to avoid
doing unnecessary recalculations in fast-path, we can reuse
next pointer of the last fragment, idea here is borrowed from
ZERO_OR_NULL_PTR(), which should keep the perf_output_sample()
path for PERF_SAMPLE_RAW minimal.

This facility is needed for BPF's event output helper as a first
user that will, in a follow-up, add an additional perf_raw_frag
to its perf_raw_record in order to be able to more efficiently
dump skb context after a linear head meta data related to it.
skbs can be non-linear and thus need a custom output function to
dump buffers. Currently, the skb data needs to be copied twice;
with the help of __output_custom() this work only needs to be
done once. Future users could be things like XDP/BPF programs
that work on different context though and would thus also have
a different callback function.

The few users of raw records are adapted to initialize their frag
data from the raw record itself, no change in behavior for them.
The code is based upon a PoC diff provided by Peter Zijlstra [1].

  [1] http://thread.gmane.org/gmane.linux.network/421294

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15 14:23:56 -07:00
Rafael J. Wysocki
406f992e4a x86 / hibernate: Use hlt_play_dead() when resuming from hibernation
On Intel hardware, native_play_dead() uses mwait_play_dead() by
default and only falls back to the other methods if that fails.
That also happens during resume from hibernation, when the restore
(boot) kernel runs disable_nonboot_cpus() to take all of the CPUs
except for the boot one offline.

However, that is problematic, because the address passed to
__monitor() in mwait_play_dead() is likely to be written to in the
last phase of hibernate image restoration and that causes the "dead"
CPU to start executing instructions again.  Unfortunately, the page
containing the address in that CPU's instruction pointer may not be
valid any more at that point.

First, that page may have been overwritten with image kernel memory
contents already, so the instructions the CPU attempts to execute may
simply be invalid.  Second, the page tables previously used by that
CPU may have been overwritten by image kernel memory contents, so the
address in its instruction pointer is impossible to resolve then.

A report from Varun Koyyalagunta and investigation carried out by
Chen Yu show that the latter sometimes happens in practice.

To prevent it from happening, temporarily change the smp_ops.play_dead
pointer during resume from hibernation so that it points to a special
"play dead" routine which uses hlt_play_dead() and avoids the
inadvertent "revivals" of "dead" CPUs this way.

A slightly unpleasant consequence of this change is that if the
system is hibernated with one or more CPUs offline, it will generally
draw more power after resume than it did before hibernation, because
the physical state entered by CPUs via hlt_play_dead() is higher-power
than the mwait_play_dead() one in the majority of cases.  It is
possible to work around this, but it is unclear how much of a problem
that's going to be in practice, so the workaround will be implemented
later if it turns out to be necessary.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=106371
Reported-by: Varun Koyyalagunta <cpudebug@centtech.com>
Original-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 22:42:48 +02:00
Eric W. Biederman
726a4994b0 cgroupns: Only allow creation of hierarchies in the initial cgroup namespace
Unprivileged users can't use hierarchies if they create them as they do not
have privilieges to the root directory.

Which means the only thing a hiearchy created by an unprivileged user
is good for is expanding the number of cgroup links in every css_set,
which is a DOS attack.

We could allow hierarchies to be created in namespaces in the initial
user namespace.  Unfortunately there is only a single namespace for
the names of heirarchies, so that is likely to create more confusion
than not.

So do the simple thing and restrict hiearchy creation to the initial
cgroup namespace.

Cc: stable@vger.kernel.org
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-15 08:04:27 -04:00
Eric W. Biederman
eedd0f4cbf cgroupns: Close race between cgroup_post_fork and copy_cgroup_ns
In most code paths involving cgroup migration cgroup_threadgroup_rwsem
is taken.  There are two exceptions:

- remove_tasks_in_empty_cpuset calls cgroup_transfer_tasks
- vhost_attach_cgroups_work calls cgroup_attach_task_all

With cgroup_threadgroup_rwsem held it is guaranteed that cgroup_post_fork
and copy_cgroup_ns will reference the same css_set from the process calling
fork.

Without such an interlock there process after fork could reference one
css_set from it's new cgroup namespace and another css_set from
task->cgroups, which semantically is nonsensical.

Cc: stable@vger.kernel.org
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-15 07:56:38 -04:00
Eric W. Biederman
7bd8830875 cgroupns: Fix the locking in copy_cgroup_ns
If "clone(CLONE_NEWCGROUP...)" is called it results in a nice lockdep
valid splat.

In __cgroup_proc_write the lock ordering is:
     cgroup_mutex -- through cgroup_kn_lock_live
     cgroup_threadgroup_rwsem

In copy_process the guts of clone the lock ordering is:
     cgroup_threadgroup_rwsem -- through threadgroup_change_begin
     cgroup_mutex -- through copy_namespaces -- copy_cgroup_ns

lockdep reports some a different call chains for the first ordering of
cgroup_mutex and cgroup_threadgroup_rwsem but it is harder to trace.
This is most definitely deadlock potential under the right
circumstances.

Fix this by by skipping the cgroup_mutex and making the locking in
copy_cgroup_ns mirror the locking in cgroup_post_fork which also runs
during fork under the cgroup_threadgroup_rwsem.

Cc: stable@vger.kernel.org
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-15 07:56:32 -04:00
Thomas Gleixner
4df8374254 rcu: Convert rcutree to hotplug state machine
Straight forward conversion to the state machine. Though the question arises
whether this needs really all these state transitions to work.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.982013161@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:41:44 +02:00
Richard Weinberger
31487f8328 smp/cfd: Convert core to hotplug state machine
Install the callbacks via the state machine. They are installed at runtime so
smpcfd_prepare_cpu() needs to be invoked by the boot-CPU.

Signed-off-by: Richard Weinberger <richard@nod.at>
[ Added the dropped CPU dying case back in. ]
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Davidlohr Bueso <dave@stgolabs>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.818376366@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:41:43 +02:00
Sebastian Andrzej Siewior
e722d8daaf profile: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs. A lot of code is removed because
the for-loop is used and create_hash_tables() is removed since its purpose
is covered by the startup / teardown hooks.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.649867675@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:41:42 +02:00
Richard Cochran
24f73b9971 timers/core: Convert to hotplug state machine
When tearing down, call timers_dead_cpu() before notify_dead().
There is a hidden dependency between:

 - timers
 - block multiqueue
 - rcutree

If timers_dead_cpu() comes later than blk_mq_queue_reinit_notify()
that latter function causes a RCU stall.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.566790058@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:41:42 +02:00
Thomas Gleixner
27590dc17b hrtimer: Convert to hotplug state machine
Split out the clockevents callbacks instead of piggybacking them on
hrtimers.

This gets rid of a POST_DEAD user. See commit:

  54e88fad22 ("sched: Make sure timers have migrated before killing the migration_thread")

We just move the callback state to the proper place in the state machine.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.485419196@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:41:37 +02:00
Linus Torvalds
fa3a9f5744 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "20 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  m32r: fix build warning about putc
  mm: workingset: printk missing log level, use pr_info()
  mm: thp: refix false positive BUG in page_move_anon_rmap()
  mm: rmap: call page_check_address() with sync enabled to avoid racy check
  mm: thp: move pmd check inside ptl for freeze_page()
  vmlinux.lds: account for destructor sections
  gcov: add support for gcc version >= 6
  mm, meminit: ensure node is online before checking whether pages are uninitialised
  mm, meminit: always return a valid node from early_pfn_to_nid
  kasan/quarantine: fix bugs on qlist_move_cache()
  uapi: export lirc.h header
  madvise_free, thp: fix madvise_free_huge_pmd return value after splitting
  Revert "scripts/gdb: add documentation example for radix tree"
  Revert "scripts/gdb: add a Radix Tree Parser"
  scripts/gdb: Perform path expansion to lx-symbol's arguments
  scripts/gdb: add constants.py to .gitignore
  scripts/gdb: rebuild constants.py on dependancy change
  scripts/gdb: silence 'nothing to do' message
  kasan: add newline to messages
  mm, compaction: prevent VM_BUG_ON when terminating freeing scanner
2016-07-15 16:00:18 +09:00
Linus Torvalds
d83a4c116c Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
 "Fix a CPU hotplug related corruption of the load average that got
  introduced in this merge window"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Correct off by one bug in load migration calculation
2016-07-15 15:02:49 +09:00
Florian Meier
d02038f972 gcov: add support for gcc version >= 6
Link: http://lkml.kernel.org/r/20160701130914.GA23225@styxhp
Signed-off-by: Florian Meier <Florian.Meier@informatik.uni-erlangen.de>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-15 14:54:27 +09:00
Steve Grubb
0b7a0fdb29 audit: fix whitespace in CWD record
Fix the whitespace in the CWD record

Signed-off-by: Steve Grubb <sgrubb@redhat.com>
[PM: fixed subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-07-14 17:47:43 -04:00
Rik van Riel
553bf6bbfd sched/cputime: Drop local_irq_save/restore from irqtime_account_irq()
Paolo pointed out that irqs are already blocked when irqtime_account_irq()
is called. That means there is no reason to call local_irq_save/restore()
again.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-6-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 10:42:35 +02:00
Frederic Weisbecker
0cfdf9a198 sched/cputime: Clean up the old vtime gen irqtime accounting completely
Vtime generic irqtime accounting has been removed but there are a few
remnants to clean up:

* The vtime_accounting_cpu_enabled() check in irq entry was only used
  by CONFIG_VIRT_CPU_ACCOUNTING_GEN. We can safely remove it.

* Without the vtime_accounting_cpu_enabled(), we no longer need to
  have a vtime_common_account_irq_enter() indirect function.

* Move vtime_account_irq_enter() implementation under
  CONFIG_VIRT_CPU_ACCOUNTING_NATIVE which is the last user.

* The vtime_account_user() call was only used on irq entry for
  CONFIG_VIRT_CPU_ACCOUNTING_GEN. We can remove that too.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 10:42:35 +02:00
Rik van Riel
b58c358405 sched/cputime: Replace VTIME_GEN irq time code with IRQ_TIME_ACCOUNTING code
The CONFIG_VIRT_CPU_ACCOUNTING_GEN irq time tracking code does not
appear to currently work right.

On CPUs without nohz_full=, only tick based irq time sampling is
done, which breaks down when dealing with a nohz_idle CPU.

On firewalls and similar systems, no ticks may happen on a CPU for a
while, and the irq time spent may never get accounted properly. This
can cause issues with capacity planning and power saving, which use
the CPU statistics as inputs in decision making.

Remove the VTIME_GEN vtime irq time code, and replace it with the
IRQ_TIME_ACCOUNTING code, when selected as a config option by the user.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 10:42:34 +02:00
Rik van Riel
5743021831 sched/cputime: Count actually elapsed irq & softirq time
Currently, if there was any irq or softirq time during 'ticks'
jiffies, the entire period will be accounted as irq or softirq
time.

This is inaccurate if only a subset of the time was actually spent
handling irqs, and could conceivably mis-count all of the ticks during
a period as irq time, when there was some irq and some softirq time.

This can actually happen when irqtime_account_process_tick is called
from account_idle_ticks, which can pass a larger number of ticks down
all at once.

Fix this by changing irqtime_account_hi_update(), irqtime_account_si_update(),
and steal_account_process_ticks() to work with cputime_t time units, and
return the amount of time spent in each mode.

Rename steal_account_process_ticks() to steal_account_process_time(), to
reflect that time is now accounted in cputime_t, instead of ticks.

Additionally, have irqtime_account_process_tick() take into account how
much time was spent in each of steal, irq, and softirq time.

The latter could help improve the accuracy of cputime
accounting when returning from idle on a NO_HZ_IDLE CPU.

Properly accounting how much time was spent in hardirq and
softirq time will also allow the NO_HZ_FULL code to re-use
these same functions for hardirq and softirq accounting.

Signed-off-by: Rik van Riel <riel@redhat.com>
[ Make nsecs_to_cputime64() actually return cputime64_t. ]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 10:42:34 +02:00
Ingo Molnar
cefef3a762 Merge branch 'sched/core' into timers/nohz, to avoid conflicts in upcoming patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 10:37:48 +02:00
Thomas Gleixner
7ee681b252 workqueue: Convert to state machine callbacks
Get rid of the prio ordering of the separate notifiers and use a proper state
callback pair.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153335.197083890@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 09:34:43 +02:00
Thomas Gleixner
00e16c3d68 perf/core: Convert to hotplug state machine
Actually a nice symmetric startup/teardown pair which fits properly into
the state machine concept. In the long run we should be able to invoke
the startup callback for the boot CPU via the state machine and get
rid of the init function which invokes it on the boot CPU.

Note: This comes actually before the perf hardware callbacks. In the notifier
model the hardware callbacks have a higher priority than the core
callback. But that's solely for CPU offline so that hardware migration of
events happens before the core is notified about the outgoing CPU.

With the symetric state array model we have the following ordering:

 UP:     core -> hardware
 DOWN:   hardware -> core

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153333.587514098@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 09:34:31 +02:00
Thomas Gleixner
6a4e24518c cpu/hotplug: Handle early registration gracefully
We switched the hotplug machinery to smpboot threads. Early registration of
hotplug callbacks, i.e. from do_pre_smp_initcalls(), happens before the
threads are initialized. Instead of moving the thread init, we simply handle
it in the hotplug code itself and invoke the function directly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153332.896450738@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 09:34:25 +02:00
Greg Kroah-Hartman
6c71ee3b61 Third set of IIO new device support, features and cleanups for the 4.8 cycle.
New core features
 - Selection of the clock source for IIO timestamps.  This is done per device
   as it makes little sense to have events in one timebase and data timestamped
   on another.  Biggest reason for this is that we currently use a clock
   source which is non monotonic which can result in 'interesting' data sets.
   (Includes export for get_monotonic_corse64 which Thomas Gleixner didn't mind
    in an earlier version.)
 - MAINTAINERS add the git tree to the list for IIO.
 
 New device support + a kind of indirect staging graduation.
 * Broadcom iproc-static-adc
   - new driver
 * mcp4531
   - support for MCP454x, MCP456x, MCP464x and MCP466x potentiometers
 * mpu6050
   - support the IC20608 6 axis motion tracking device
 * st-sensors
   - support the lis3l02dq + drop the lis3l02dq driver from staging.
   The general purpose driver is missing event support, but good to get
   rid of this driver which was rather long in the tooth.
 
 New driver features
 * ak8975
   - Add vid regulator support and refactor handling in general.
   - Allow a delay after enabling regulators.
   - Runtime and system PM.
 * bmg160
   - filter frequency control support.
 * bmp280
   - SPI device support.
   - EOC interrupt support for the BMP085
   - power management support.
   - supply regulator support.
   - reset gpio support
   - dt bindings for reset gpio and regulators.
   - of table to support device tree registration
 * max1363
   - Device tree bindings.
 * mcp4531
   - Device tree bindings.
 * st-pressure
   - temperature channels as part of triggered buffer (previously not due
   probably to alignment issues - see below).
   - lps22hb open drain interrupt support.
   - lps22hb temperature channel support
 
 Cleanups and reworkings.
 * numerous ADC drivers
   - ensure the iio_dev->dev.of_node is set to the parent dev.of_node so
   as to allow client bindings to find the device.
 * ak8975
   - Fix incorrect handling of missing regulator
   - make sure power is down and remove.
 * bmp280
   - read the calibration data only once as it doesn't change.
 * isl29125
   - Use a few macros to make code a touch more readable.
 * mma8452
   - fix a memory leak on error.
   - drop an unecessary bit of return value handling.
 * potentiometer kconfig
   - typo fix.
 * st-pressure
   - drop some uninformative default assignments of elements of the channel
   array structure (aids readability).
 * st-sensors
   - Harden interrupt handling considerably.  These are actually all using
   level interrupts, but at least two known boards have them wired to
   edge only interrupt chips.  Hence a slightly interesting bit of handling
   is needed in which we first allow for the easy option (level triggered) and
   secondly check the status registers before reenabling edge interrupts and
   fall back to a tight loop in the thread until we successfully clear the
   interrupt.  No harm is done if we never succeed in doing so.  It's an odd
   patch that has been through a lot of revisions to reach a consensus on how
   to handle what is basically broken hardware (which the previous defaults
   allowed to kind of work).
   - Fix alignment to defined storagebytes boundaries.
   - Ensure alignment of power of 2 byte boundaries.  This has always in theory
   been part of the ABI of IIO, but we missed a few that snuck in that need
   fixing.  The effect was minor as they were only followed by timestamp
   channels which were correctly aligned,
   - Add some docs to explain the gain calculations.
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Merge tag 'iio-for-4.8c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Third set of IIO new device support, features and cleanups for the 4.8 cycle.

New core features
- Selection of the clock source for IIO timestamps.  This is done per device
  as it makes little sense to have events in one timebase and data timestamped
  on another.  Biggest reason for this is that we currently use a clock
  source which is non monotonic which can result in 'interesting' data sets.
  (Includes export for get_monotonic_corse64 which Thomas Gleixner didn't mind
   in an earlier version.)
- MAINTAINERS add the git tree to the list for IIO.

New device support + a kind of indirect staging graduation.
* Broadcom iproc-static-adc
  - new driver
* mcp4531
  - support for MCP454x, MCP456x, MCP464x and MCP466x potentiometers
* mpu6050
  - support the IC20608 6 axis motion tracking device
* st-sensors
  - support the lis3l02dq + drop the lis3l02dq driver from staging.
  The general purpose driver is missing event support, but good to get
  rid of this driver which was rather long in the tooth.

New driver features
* ak8975
  - Add vid regulator support and refactor handling in general.
  - Allow a delay after enabling regulators.
  - Runtime and system PM.
* bmg160
  - filter frequency control support.
* bmp280
  - SPI device support.
  - EOC interrupt support for the BMP085
  - power management support.
  - supply regulator support.
  - reset gpio support
  - dt bindings for reset gpio and regulators.
  - of table to support device tree registration
* max1363
  - Device tree bindings.
* mcp4531
  - Device tree bindings.
* st-pressure
  - temperature channels as part of triggered buffer (previously not due
  probably to alignment issues - see below).
  - lps22hb open drain interrupt support.
  - lps22hb temperature channel support

Cleanups and reworkings.
* numerous ADC drivers
  - ensure the iio_dev->dev.of_node is set to the parent dev.of_node so
  as to allow client bindings to find the device.
* ak8975
  - Fix incorrect handling of missing regulator
  - make sure power is down and remove.
* bmp280
  - read the calibration data only once as it doesn't change.
* isl29125
  - Use a few macros to make code a touch more readable.
* mma8452
  - fix a memory leak on error.
  - drop an unecessary bit of return value handling.
* potentiometer kconfig
  - typo fix.
* st-pressure
  - drop some uninformative default assignments of elements of the channel
  array structure (aids readability).
* st-sensors
  - Harden interrupt handling considerably.  These are actually all using
  level interrupts, but at least two known boards have them wired to
  edge only interrupt chips.  Hence a slightly interesting bit of handling
  is needed in which we first allow for the easy option (level triggered) and
  secondly check the status registers before reenabling edge interrupts and
  fall back to a tight loop in the thread until we successfully clear the
  interrupt.  No harm is done if we never succeed in doing so.  It's an odd
  patch that has been through a lot of revisions to reach a consensus on how
  to handle what is basically broken hardware (which the previous defaults
  allowed to kind of work).
  - Fix alignment to defined storagebytes boundaries.
  - Ensure alignment of power of 2 byte boundaries.  This has always in theory
  been part of the ABI of IIO, but we missed a few that snuck in that need
  fixing.  The effect was minor as they were only followed by timestamp
  channels which were correctly aligned,
  - Add some docs to explain the gain calculations.
2016-07-14 12:05:29 +09:00
Linus Torvalds
f97d10454e Merge branches 'perf-urgent-for-linus' and 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf and timer fixes from Ingo Molnar:
 "A fix for a posix CPU timers bug, and a perf printk message fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Fix bogus kernel printk, again

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix_cpu_timer: Exit early when process has been reaped
2016-07-14 05:44:47 +09:00
Thomas Gleixner
e877bde234 Merge branch 'core/urgent' into smp/hotplug to pick up dependencies 2016-07-13 17:03:30 +02:00
Thomas Gleixner
e1c4cde62b Merge branch 'core/rcu' into smp/hotplug to pick up dependencies 2016-07-13 17:03:17 +02:00
Thomas Gleixner
54f5449677 Merge branch 'timers/core' into smp/hotplug to pick up dependencies 2016-07-13 17:01:51 +02:00
Thomas Gleixner
d60585c576 sched/core: Correct off by one bug in load migration calculation
The move of calc_load_migrate() from CPU_DEAD to CPU_DYING did not take into
account that the function is now called from a thread running on the outgoing
CPU. As a result a cpu unplug leakes a load of 1 into the global load
accounting mechanism.

Fix it by adjusting for the currently running thread which calls
calc_load_migrate().

Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: rt@linutronix.de
Cc: shreyas@linux.vnet.ibm.com
Fixes: e9cd8fa4fc: ("sched/migration: Move calc_load_migrate() into CPU_DYING")
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1607121744350.4083@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-13 14:58:20 +02:00
Thomas Gleixner
a7c734140a cpu/hotplug: Keep enough storage space if SMP=n to avoid array out of bounds scribble
Xiaolong Ye reported lock debug warnings triggered by the following commit:

  8de4a0066106 ("perf/x86: Convert the core to the hotplug state machine")

The bug is the following: the cpuhp_bp_states[] array is cut short when
CONFIG_SMP=n, but the dynamically registered callbacks are stored nevertheless
and happily scribble outside of the array bounds...

We need to store them in case that the state is unregistered so we can invoke
the teardown function. That's independent of CONFIG_SMP. Make sure the array
is large enough.

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Borowski <kilobyte@angband.pl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: lkp@01.org
Cc: stable@vger.kernel.org
Cc: tipbuild@zytor.com
Fixes: cff7d378d3 "cpu/hotplug: Convert to a state machine for the control processor"
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1607122144560.4083@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-13 09:29:39 +02:00
Paul Gortmaker
a536a6e13e bpf: make inode code explicitly non-modular
The Kconfig currently controlling compilation of this code is:

init/Kconfig:config BPF_SYSCALL
init/Kconfig:   bool "Enable bpf() system call"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modular infrastructure use, so that
when reading the driver there is no doubt it is builtin-only.

Note that MODULE_ALIAS is a no-op for non-modular code.

We replace module.h with init.h since the file does use __init.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-11 13:52:43 -07:00
Alexander Popov
a1b7b1a57b irqdomain: Fix irq_domain_alloc_irqs_recursive() error handling
If an irq_domain is auto-recursive and irq_domain_alloc_irqs_recursive()
for its parent has returned an error, then do return and avoid calling
irq_domain_free_irqs_recursive() uselessly, because:
- if domain->ops->alloc() had failed for an auto-recursive irq_domain,
   then irq_domain_free_irqs_recursive() had already been called;
- if domain->ops->alloc() had failed for a not auto-recursive irq_domain,
   then there is nothing to free at all.

Signed-off-by: Alexander Popov <alex.popov@linux.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1467505448-2850-1-git-send-email-alex.popov@linux.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-11 17:23:48 +02:00
Alexey Dobriyan
2c13ce8f6b posix_cpu_timer: Exit early when process has been reaped
Variable "now" seems to be genuinely used unintialized
if branch

	if (CPUCLOCK_PERTHREAD(timer->it_clock)) {

is not taken and branch

	if (unlikely(sighand == NULL)) {

is taken. In this case the process has been reaped and the timer is marked as
disarmed anyway. So none of the postprocessing of the sample is
required. Return right away.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20160707223911.GA26483@p183.telecom.by
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-11 17:20:12 +02:00
Ingo Molnar
44530d588e Revert "perf/x86/intel, watchdog: Switch NMI watchdog to ref cycles on x86"
This reverts commit 2c95afc1e8.

Stephane reported the following regression:

 > Since Andi added:
 >
 > commit 2c95afc1e8
 > Author: Andi Kleen <ak@linux.intel.com>
 > Date:   Thu Jun 9 06:14:38 2016 -0700
 >
 >    perf/x86/intel, watchdog: Switch NMI watchdog to ref cycles on x86
 >
 > $ perf stat -e ref-cycles ls
 >   <not counted> ....
 >
 > fails systematically because the ref-cycles is now used by the
 > watchdog and given this is a system-wide pinned event, it monopolizes
 > the fixed counter 2 which is the only counter able to measure this event.

Since the next merge window is near, fix the regression for now
by reverting the commit.

Reported-by: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10 20:58:36 +02:00
Daniel Bristot de Oliveira
748c7201e6 sched/core: Panic on scheduling while atomic bugs if kernel.panic_on_warn is set
Currently, a schedule while atomic error prints the stack trace to the
kernel log and the system continue running.

Although it is possible to collect the kernel log messages and analyze
it, often more information are needed. Furthermore, keep the system
running is not always the best choice. For example, when the preempt
count underflows the system will not stop to complain about scheduling
while atomic, so the kernel log can wrap around overwriting the first
stack trace, tuning the analysis even more challenging.

This patch uses the kernel.panic_on_warn sysctl to help out on these
more complex situations.

When kernel.panic_on_warn is set to 1, the kernel will panic() in the
schedule while atomic detection.

The default value of the sysctl is 0, maintaining the current behavior.

Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Reviewed-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e8f7b80f353aa22c63bd8557208163989af8493d.1464983675.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-10 20:17:27 +02:00
Rafael J. Wysocki
4c0b6c10fb PM / hibernate: Image data protection during restoration
Make it possible to protect all pages holding image data during
hibernate image restoration by setting them read-only (so as to
catch attempts to write to those pages after image data have been
stored in them).

This adds overhead to image restoration code (it may cause large
page mappings to be split as a result of page flags changes) and
the errors it protects against should never happen in theory, so
the feature is only active after passing hibernate=protect_image
to the command line of the restore kernel.

Also it only is built if CONFIG_DEBUG_RODATA is set.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-10 02:12:10 +02:00
Rafael J. Wysocki
d5f32af310 PM / hibernate: Add missing braces in __register_nosave_region()
One branch of an if/else statement in __register_nosave_region() is
formatted against the kernel coding style which causes the code to
look slightly odd.  To fix that, add missing braces to it.

No functional changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-10 01:37:35 +02:00
Rafael J. Wysocki
ef96f639ea PM / hibernate: Clean up comments in snapshot.c
Many comments in kernel/power/snapshot.c do not follow the general
comment formatting rules.  They look odd, some of them are outdated
too, some are hard to parse and generally difficult to understand.

Clean them up to make them easier to comprehend.

No functional changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-10 01:37:26 +02:00
Rafael J. Wysocki
efd5a85242 PM / hibernate: Clean up function headers in snapshot.c
The formatting of some function headers in kernel/power/snapshot.c
is not consistent with the general kernel coding style and with the
formatting of some other function headers in the same file.

Make all of them follow the same formatting convention.

No functional changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-10 01:37:20 +02:00
Rafael J. Wysocki
2f88e41a22 PM / hibernate: Add missing braces in hibernate_setup()
Make hibernate_setup() follow the coding style more closely by adding
some missing braces to the if () statement in it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-10 01:37:13 +02:00
Zhao Lei
277a13e4f0 sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together
In current code, we can get cpuacct data from several files,
but each file has various limitations.

For example:

 - We can get CPU usage in user and kernel mode via cpuacct.stat,
   but we can't get detailed data about each CPU.

 - We can get each CPU's kernel mode usage in cpuacct.usage_percpu_sys,
   but we can't get user mode usage data at the same time.

This patch introduces cpuacct.usage_all, to show all detailed CPU
accounting data together:

 # cat cpuacct.usage_all
 cpu user system
 0 3809760299 5807968992
 1 3250329855 454612211
 ..

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
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/7744460969edd7caaf0e903592ee52353ed9bdd6.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-09 13:56:15 +02:00
Zhao Lei
8e546bfafb sched/cpuacct: Use loop to consolidate code in cpuacct_stats_show()
In cpuacct_stats_show() we currently we have copies of similar code,
for each cpustat(system/user) variant.

Use a loop instead to consolidate the code. This will also work better
if we extend the CPUACCT_STAT_NSTATS type.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
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/b0597d4224655e9f333f1a6224ed9654c7d7d36a.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-09 13:56:15 +02:00
Zhao Lei
9acacc2ac5 sched/cpuacct: Merge cpuacct_usage_index and cpuacct_stat_index enums
These two types have similar function, no need to separate them.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
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/436748885270d64363c7dc67167507d486c2057a.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-09 13:56:15 +02:00
Alexei Starovoitov
606274c5ab bpf: introduce bpf_get_current_task() helper
over time there were multiple requests to access different data
structures and fields of task_struct current, so finally add
the helper to access 'current' as-is. Tracing bpf programs will do
the rest of walking the pointers via bpf_probe_read().
Note that current can be null and bpf program has to deal it with,
but even dumb passing null into bpf_probe_read() is still safe.

Suggested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-09 00:00:16 -04:00
Rafael J. Wysocki
63f9ccb895 Merge back earlier suspend/hibernation changes for v4.8. 2016-07-08 23:14:17 +02:00
Linus Torvalds
369da7fc6d Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two load-balancing fixes for cgroups-intense workloads"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix calc_cfs_shares() fixed point arithmetics width confusion
  sched/fair: Fix effective_load() to consistently use smoothed load
2016-07-08 09:04:34 -07:00
Ingo Molnar
9e7f7f5425 Merge branch 'x86/mm' into x86/boot, to pick up dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 17:27:47 +02:00
Ingo Molnar
4b4b20852d Merge branch 'timers/fast-wheel' into timers/core 2016-07-07 10:35:28 +02:00
Anna-Maria Gleixner
f00c0afdfa timers: Implement optimization for same expiry time in mod_timer()
The existing optimization for same expiry time in mod_timer() checks whether
the timer expiry time is the same as the new requested expiry time. In the old
timer wheel implementation this does not take the slack batching into account,
neither does the new implementation evaluate whether the new expiry time will
requeue the timer to the same bucket.

To optimize that, we can calculate the resulting bucket and check if the new
expiry time is different from the current expiry time. This calculation
happens outside the base lock held region. If the resulting bucket is the same
we can avoid taking the base lock and requeueing the timer.

If the timer needs to be requeued then we have to check under the base lock
whether the base time has changed between the lockless calculation and taking
the lock. If it has changed we need to recalculate under the lock.

This optimization takes effect for timers which are enqueued into the less
granular wheel levels (1 and above). With a simple test case the functionality
has been verified:

            Before        After
 Match:       5.5%        86.6%
 Requeue:    94.5%        13.4%
 Recalc:                  <0.01%

In the non optimized case the timer is requeued in 94.5% of the cases. With
the index optimization in place the requeue rate drops to 13.4%. The case
where the lockless index calculation has to be redone is less than 0.01%.

With a real world test case (networking) we observed the following changes:

            Before        After
 Match:      97.8%        99.7%
 Requeue:     2.2%         0.3%
 Recalc:                  <0.001%

That means two percent fewer lock/requeue/unlock operations done in one of
the hot path use cases of timers.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.778527749@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:12 +02:00
Anna-Maria Gleixner
ffdf047728 timers: Split out index calculation
For further optimizations we need to seperate index calculation
from queueing. No functional change.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.691159619@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:12 +02:00
Thomas Gleixner
4e85876a9d timers: Only wake softirq if necessary
With the wheel forwading in place and with the HZ=1000 4ms folding we can
avoid running the softirq at all.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.607650550@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:11 +02:00
Thomas Gleixner
a683f390b9 timers: Forward the wheel clock whenever possible
The wheel clock is stale when a CPU goes into a long idle sleep. This has the
side effect that timers which are queued end up in the outer wheel levels.
That results in coarser granularity.

To solve this, we keep track of the idle state and forward the wheel clock
whenever possible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.512039360@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:11 +02:00
Thomas Gleixner
ff00673292 timers/nohz: Remove pointless tick_nohz_kick_tick() function
This was a failed attempt to optimize the timer expiry in idle, which was
disabled and never revisited. Remove the cruft.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.431073782@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:10 +02:00
Anna-Maria Gleixner
236968383c timers: Optimize collect_expired_timers() for NOHZ
After a NOHZ idle sleep the timer wheel must be forwarded to current jiffies.
There might be expired timers so the current code loops and checks the expired
buckets for timers. This can take quite some time for long NOHZ idle periods.

The pending bitmask in the timer base allows us to do a quick search for the
next expiring timer and therefore a fast forward of the base time which
prevents pointless long lasting loops.

For a 3 seconds idle sleep this reduces the catchup time from ~1ms to 5us.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.351296290@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:10 +02:00
Anna-Maria Gleixner
73420fea80 timers: Move __run_timers() function
Move __run_timers() below __next_timer_interrupt() and next_pending_bucket()
in preparation for __run_timers() NOHZ optimization.

No functional change.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.271872665@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:09 +02:00
Thomas Gleixner
53bf837b78 timers: Remove set_timer_slack() leftovers
We now have implicit batching in the timer wheel. The slack API is no longer
used, so remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andrew F. Davis <afd@ti.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Pali Rohár <pali.rohar@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.189813118@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 10:35:09 +02:00