Commit graph

41 commits

Author SHA1 Message Date
Kees Cook
be814112fd time: Remove CONFIG_TIMER_STATS
Currently CONFIG_TIMER_STATS exposes process information across namespaces:

kernel/time/timer_list.c print_timer():

        SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);

/proc/timer_list:

 #11: <0000000000000000>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570

Given that the tracer can give the same information, this patch entirely
removes CONFIG_TIMER_STATS.

Change-Id: I66e06ae2d6e32c309824310d3d9bf54d1047eab1
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: linux-doc@vger.kernel.org
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Xing Gao <xgao01@email.wm.edu>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jessica Frazelle <me@jessfraz.com>
Cc: kernel-hardening@lists.openwall.com
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-api@vger.kernel.org
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: http://lkml.kernel.org/r/20170208192659.GA32582@beast
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: dfb4357da6ddbdf57d583ba64361c9d792b0e0b1
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[ohaugan@codeaurora.org: Fixed merge conflicts]
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2017-05-16 14:16:43 -07:00
Prasad Sodagudi
883e3ea07e sched: Add a check for cpu unbound deferrable timers
Add a check for cpu unbound deferrable timer expiry and raise
softirq for handling the expired timers so that the CPU can
process the cpu unbound deferrable times as early as possible
when a cpu tries to enter/exit idle loop.

Change-Id: Ieffa74fa22a4d25493f5590b5ac1e0d784fcbbad
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
2017-04-21 17:24:12 -07:00
Douglas Anderson
e489bf2659 timers: Fix documentation for schedule_timeout() and similar
The documentation for schedule_timeout(), schedule_hrtimeout(), and
schedule_hrtimeout_range() all claim that the routines couldn't possibly
return early if the task state was TASK_UNINTERRUPTIBLE. This is simply
not true since wake_up_process() will cause those routines to exit early.

We cannot make schedule_[hr]timeout() loop until the timeout expires if the
task state is uninterruptible because we have users which rely on the
existing and designed behaviour.

Make the documentation match the (correct) implementation.

schedule_hrtimeout() returns -EINTR even when a uninterruptible task was
woken up. This might look strange, but making the return code depend on the
state is too much of an effort as it would affect all the call sites. There
is no value in doing so, but we spell it out clearly in the documentation.

Change-Id: I3e9bf91e7d285abcac134e32b02131b999d79f40
Suggested-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: huangtao@rock-chips.com
Cc: heiko@sntech.de
Cc: broonie@kernel.org
Cc: briannorris@chromium.org
Cc: Andreas Mohr <andi@lisas.de>
Cc: linux-rockchip@lists.infradead.org
Cc: tony.xie@rock-chips.com
Cc: John Stultz <john.stultz@linaro.org>
Cc: linux@roeck-us.net
Cc: tskd08@gmail.com
Link: http://lkml.kernel.org/r/1477065531-30342-2-git-send-email-dianders@chromium.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: 4b7e9cf9c84b09adc428e0433cd376b91f9c52a7
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Runmin Wang <runminw@codeaurora.org>
2017-01-05 17:29:10 -08:00
Douglas Anderson
c51fd6364e timers: Fix usleep_range() in the context of wake_up_process()
Users of usleep_range() expect that it will _never_ return in less time
than the minimum passed parameter. However, nothing in the code ensures
this, when the sleeping task is woken by wake_up_process() or any other
mechanism which can wake a task from uninterruptible state.

Neither usleep_range() nor schedule_hrtimeout_range*() have any protection
against wakeups. schedule_hrtimeout_range*() is designed this way despite
the fact that the API documentation does not mention it.

msleep() already has code to handle this case since it will loop as long
as there was still time left.  usleep_range() has no such loop, add it.

Presumably this problem was not detected before because usleep_range() is
only used in a few places and the function is mostly used in contexts which
are not exposed to wakeups of any form.

An effort was made to look for users relying on the old behavior by
looking for usleep_range() in the same file as wake_up_process().
No problems were found by this search, though it is conceivable that
someone could have put the sleep and wakeup in two different files.

An effort was made to ask several upstream maintainers if they were aware
of people relying on wake_up_process() to wake up usleep_range(). No
maintainers were aware of that but they were aware of many people relying
on usleep_range() never returning before the minimum.

Change-Id: Ia403f0dc9cac711c8a4b6fcc4cf0094ad1358ed7
Reported-by: Tao Huang <huangtao@rock-chips.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: heiko@sntech.de
Cc: broonie@kernel.org
Cc: briannorris@chromium.org
Cc: Andreas Mohr <andi@lisas.de>
Cc: linux-rockchip@lists.infradead.org
Cc: tony.xie@rock-chips.com
Cc: John Stultz <john.stultz@linaro.org>
Cc: djkurtz@chromium.org
Cc: linux@roeck-us.net
Cc: tskd08@gmail.com
Link: http://lkml.kernel.org/r/1477065531-30342-1-git-send-email-dianders@chromium.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: 6c5e9059692567740a4ee51530dffe51a4b9584d
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Runmin Wang <runminw@codeaurora.org>
2017-01-05 17:28:28 -08:00
Thomas Gleixner
8965291e3d timers: Plug locking race vs. timer migration
Linus noticed that lock_timer_base() lacks a READ_ONCE() for accessing the
timer flags. As a consequence the compiler is allowed to reload the flags
between the initial check for TIMER_MIGRATION and the following timer base
computation and the spin lock of the base.

While this has not been observed (yet), we need to make sure that it never
happens.

Change-Id: I577327e02ab77b6de951ac2aa936cb5d5a4f477a
Fixes: 0eeda71bc3 ("timer: Replace timer base by a cpu index")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1610241711220.4983@nanos
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Git-commit: b831275a3553c32091222ac619cfddd73a5553fb
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[runminw@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Runmin Wang <runminw@codeaurora.org>
2017-01-05 17:27:10 -08:00
Vikram Mulukutla
4142e30898 timer: Don't wait for running timers when migrating during isolation
A CPU that is isolated needs to have its timers migrated off to
another CPU. If while migrating timers, there is a running
timer, acquiring the timer base lock after marking a CPU as
isolated will ensure that:

1) No more timers can be queued on to the isolated CPU, and
2) A running timer will finish execution on the to-be-isolated
   CPU, and so will any just expired timers since they're all
   taken off of the CPU's tvec1 in one go while the base lock
   is held.

Therefore there is no apparent reason to wait for the expired
timers to finish execution, and isolation can proceed to migrate
non-expired timers even when the expired ones are running
concurrently.

While we're here, also add a delay to the wait-loop inside
migrate_hrtimer_list to allow for store-exclusive fairness
when run_hrtimer is attempting to grab the hrtimer base
lock.

Change-Id: Ib697476c93c60e3d213aaa8fff0a2bcc2985bfce
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
2016-11-09 15:57:24 -08:00
Runmin Wang
9cc5c789d9 Merge remote-tracking branch 'msm4.4/tmp-da9a92f' into msm-4.4
* origin/tmp-da9a92f:
  arm64: kaslr: increase randomization granularity
  arm64: relocatable: deal with physically misaligned kernel images
  arm64: don't map TEXT_OFFSET bytes below the kernel if we can avoid it
  arm64: kernel: replace early 64-bit literal loads with move-immediates
  arm64: introduce mov_q macro to move a constant into a 64-bit register
  arm64: kernel: perform relocation processing from ID map
  arm64: kernel: use literal for relocated address of __secondary_switched
  arm64: kernel: don't export local symbols from head.S
  arm64: simplify kernel segment mapping granularity
  arm64: cover the .head.text section in the .text segment mapping
  arm64: move early boot code to the .init segment
  arm64: use 'segment' rather than 'chunk' to describe mapped kernel regions
  arm64: mm: Mark .rodata as RO
  Linux 4.4.16
  ovl: verify upper dentry before unlink and rename
  drm/i915: Revert DisplayPort fast link training feature
  tmpfs: fix regression hang in fallocate undo
  tmpfs: don't undo fallocate past its last page
  crypto: qat - make qat_asym_algs.o depend on asn1 headers
  xen/acpi: allow xen-acpi-processor driver to load on Xen 4.7
  File names with trailing period or space need special case conversion
  cifs: dynamic allocation of ntlmssp blob
  Fix reconnect to not defer smb3 session reconnect long after socket reconnect
  53c700: fix BUG on untagged commands
  s390: fix test_fp_ctl inline assembly contraints
  scsi: fix race between simultaneous decrements of ->host_failed
  ovl: verify upper dentry in ovl_remove_and_whiteout()
  ovl: Copy up underlying inode's ->i_mode to overlay inode
  ARM: mvebu: fix HW I/O coherency related deadlocks
  ARM: dts: armada-38x: fix MBUS_ID for crypto SRAM on Armada 385 Linksys
  ARM: sunxi/dt: make the CHIP inherit from allwinner,sun5i-a13
  ALSA: hda: add AMD Stoney PCI ID with proper driver caps
  ALSA: hda - fix use-after-free after module unload
  ALSA: ctl: Stop notification after disconnection
  ALSA: pcm: Free chmap at PCM free callback, too
  ALSA: hda/realtek - add new pin definition in alc225 pin quirk table
  ALSA: hda - fix read before array start
  ALSA: hda - Add PCI ID for Kabylake-H
  ALSA: hda/realtek: Add Lenovo L460 to docking unit fixup
  ALSA: timer: Fix negative queue usage by racy accesses
  ALSA: echoaudio: Fix memory allocation
  ALSA: au88x0: Fix calculation in vortex_wtdma_bufshift()
  ALSA: hda / realtek - add two more Thinkpad IDs (5050,5053) for tpt460 fixup
  ALSA: hda - Fix the headset mic jack detection on Dell machine
  ALSA: dummy: Fix a use-after-free at closing
  hwmon: (dell-smm) Cache fan_type() calls and change fan detection
  hwmon: (dell-smm) Disallow fan_type() calls on broken machines
  hwmon: (dell-smm) Restrict fan control and serial number to CAP_SYS_ADMIN by default
  tty/vt/keyboard: fix OOB access in do_compute_shiftstate()
  tty: vt: Fix soft lockup in fbcon cursor blink timer.
  iio:ad7266: Fix probe deferral for vref
  iio:ad7266: Fix support for optional regulators
  iio:ad7266: Fix broken regulator error handling
  iio: accel: kxsd9: fix the usage of spi_w8r8()
  staging: iio: accel: fix error check
  iio: hudmidity: hdc100x: fix incorrect shifting and scaling
  iio: humidity: hdc100x: fix IIO_TEMP channel reporting
  iio: humidity: hdc100x: correct humidity integration time mask
  iio: proximity: as3935: fix buffer stack trashing
  iio: proximity: as3935: remove triggered buffer processing
  iio: proximity: as3935: correct IIO_CHAN_INFO_RAW output
  iio: light apds9960: Add the missing dev.parent
  iio:st_pressure: fix sampling gains (bring inline with ABI)
  iio: Fix error handling in iio_trigger_attach_poll_func
  xen/balloon: Fix declared-but-not-defined warning
  perf/x86: Fix undefined shift on 32-bit kernels
  memory: omap-gpmc: Fix omap gpmc EXTRADELAY timing
  drm/vmwgfx: Fix error paths when mapping framebuffer
  drm/vmwgfx: Delay pinning fbdev framebuffer until after mode set
  drm/vmwgfx: Check pin count before attempting to move a buffer
  drm/vmwgfx: Work around mode set failure in 2D VMs
  drm/vmwgfx: Add an option to change assumed FB bpp
  drm/ttm: Make ttm_bo_mem_compat available
  drm: atmel-hlcdc: actually disable scaling when no scaling is required
  drm: make drm_atomic_set_mode_prop_for_crtc() more reliable
  drm: add missing drm_mode_set_crtcinfo call
  drm/i915: Update CDCLK_FREQ register on BDW after changing cdclk frequency
  drm/i915: Update ifdeffery for mutex->owner
  drm/i915: Refresh cached DP port register value on resume
  drm/i915/ilk: Don't disable SSC source if it's in use
  drm/nouveau/disp/sor/gf119: select correct sor when poking training pattern
  drm/nouveau: fix for disabled fbdev emulation
  drm/nouveau/fbcon: fix out-of-bounds memory accesses
  drm/nouveau/gr/gf100-: update sm error decoding from gk20a nvgpu headers
  drm/nouveau/disp/sor/gf119: both links use the same training register
  virtio_balloon: fix PFN format for virtio-1
  drm/dp/mst: Always clear proposed vcpi table for port.
  drm/amdkfd: destroy dbgmgr in notifier release
  drm/amdkfd: unbind only existing processes
  ubi: Make recover_peb power cut aware
  drm/amdgpu/gfx7: fix broken condition check
  drm/radeon: fix asic initialization for virtualized environments
  btrfs: account for non-CoW'd blocks in btrfs_abort_transaction
  percpu: fix synchronization between synchronous map extension and chunk destruction
  percpu: fix synchronization between chunk->map_extend_work and chunk destruction
  af_unix: fix hard linked sockets on overlay
  vfs: add d_real_inode() helper
  arm64: Rework valid_user_regs
  ipmi: Remove smi_msg from waiting_rcv_msgs list before handle_one_recv_msg()
  drm/mgag200: Black screen fix for G200e rev 4
  iommu/amd: Fix unity mapping initialization race
  iommu/vt-d: Enable QI on all IOMMUs before setting root entry
  iommu/arm-smmu: Wire up map_sg for arm-smmu-v3
  base: make module_create_drivers_dir race-free
  tracing: Handle NULL formats in hold_module_trace_bprintk_format()
  HID: multitouch: enable palm rejection for Windows Precision Touchpad
  HID: hiddev: validate num_values for HIDIOCGUSAGES, HIDIOCSUSAGES commands
  HID: elo: kill not flush the work
  KVM: nVMX: VMX instructions: fix segment checks when L1 is in long mode.
  kvm: Fix irq route entries exceeding KVM_MAX_IRQ_ROUTES
  KEYS: potential uninitialized variable
  ARCv2: LLSC: software backoff is NOT needed starting HS2.1c
  ARCv2: Check for LL-SC livelock only if LLSC is enabled
  ipv6: Fix mem leak in rt6i_pcpu
  cdc_ncm: workaround for EM7455 "silent" data interface
  net_sched: fix mirrored packets checksum
  packet: Use symmetric hash for PACKET_FANOUT_HASH.
  sched/fair: Fix cfs_rq avg tracking underflow
  UBIFS: Implement ->migratepage()
  mm: Export migrate_page_move_mapping and migrate_page_copy
  MIPS: KVM: Fix modular KVM under QEMU
  ARM: 8579/1: mm: Fix definition of pmd_mknotpresent
  ARM: 8578/1: mm: ensure pmd_present only checks the valid bit
  ARM: imx6ul: Fix Micrel PHY mask
  NFS: Fix another OPEN_DOWNGRADE bug
  make nfs_atomic_open() call d_drop() on all ->open_context() errors.
  nfsd: check permissions when setting ACLs
  posix_acl: Add set_posix_acl
  nfsd: Extend the mutex holding region around in nfsd4_process_open2()
  nfsd: Always lock state exclusively.
  nfsd4/rpc: move backchannel create logic into rpc code
  writeback: use higher precision calculation in domain_dirty_limits()
  thermal: cpu_cooling: fix improper order during initialization
  uvc: Forward compat ioctls to their handlers directly
  Revert "gpiolib: Split GPIO flags parsing and GPIO configuration"
  x86/amd_nb: Fix boot crash on non-AMD systems
  kprobes/x86: Clear TF bit in fault on single-stepping
  x86, build: copy ldlinux.c32 to image.iso
  locking/static_key: Fix concurrent static_key_slow_inc()
  locking/qspinlock: Fix spin_unlock_wait() some more
  locking/ww_mutex: Report recursive ww_mutex locking early
  of: irq: fix of_irq_get[_byname]() kernel-doc
  of: fix autoloading due to broken modalias with no 'compatible'
  mnt: If fs_fully_visible fails call put_filesystem.
  mnt: Account for MS_RDONLY in fs_fully_visible
  mnt: fs_fully_visible test the proper mount for MNT_LOCKED
  usb: common: otg-fsm: add license to usb-otg-fsm
  USB: EHCI: declare hostpc register as zero-length array
  usb: dwc2: fix regression on big-endian PowerPC/ARM systems
  powerpc/tm: Always reclaim in start_thread() for exec() class syscalls
  powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added
  powerpc/pseries: Fix PCI config address for DDW
  powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism
  IB/mlx4: Properly initialize GRH TClass and FlowLabel in AHs
  IB/cm: Fix a recently introduced locking bug
  EDAC, sb_edac: Fix rank lookup on Broadwell
  mac80211: Fix mesh estab_plinks counting in STA removal case
  mac80211_hwsim: Add missing check for HWSIM_ATTR_SIGNAL
  mac80211: mesh: flush mesh paths unconditionally
  mac80211: fix fast_tx header alignment
  Linux 4.4.15
  usb: dwc3: exynos: Fix deferred probing storm.
  usb: host: ehci-tegra: Grab the correct UTMI pads reset
  usb: gadget: fix spinlock dead lock in gadgetfs
  USB: mos7720: delete parport
  xhci: Fix handling timeouted commands on hosts in weird states.
  USB: xhci: Add broken streams quirk for Frescologic device id 1009
  usb: xhci-plat: properly handle probe deferral for devm_clk_get()
  xhci: Cleanup only when releasing primary hcd
  usb: musb: host: correct cppi dma channel for isoch transfer
  usb: musb: Ensure rx reinit occurs for shared_fifo endpoints
  usb: musb: Stop bulk endpoint while queue is rotated
  usb: musb: only restore devctl when session was set in backup
  usb: quirks: Add no-lpm quirk for Acer C120 LED Projector
  usb: quirks: Fix sorting
  USB: uas: Fix slave queue_depth not being set
  crypto: user - re-add size check for CRYPTO_MSG_GETALG
  crypto: ux500 - memmove the right size
  crypto: vmx - Increase priority of aes-cbc cipher
  AX.25: Close socket connection on session completion
  bpf: try harder on clones when writing into skb
  net: alx: Work around the DMA RX overflow issue
  net: macb: fix default configuration for GMAC on AT91
  neigh: Explicitly declare RCU-bh read side critical section in neigh_xmit()
  bpf, perf: delay release of BPF prog after grace period
  sock_diag: do not broadcast raw socket destruction
  Bridge: Fix ipv6 mc snooping if bridge has no ipv6 address
  ipmr/ip6mr: Initialize the last assert time of mfc entries.
  netem: fix a use after free
  esp: Fix ESN generation under UDP encapsulation
  sit: correct IP protocol used in ipip6_err
  net: Don't forget pr_fmt on net_dbg_ratelimited for CONFIG_DYNAMIC_DEBUG
  net_sched: fix pfifo_head_drop behavior vs backlog
  sdcardfs: Truncate packages_gid.list on overflow
  UPSTREAM: cdc_ncm: do not call usbnet_link_change from cdc_ncm_bind
  BACKPORT: proc: add /proc/<pid>/timerslack_ns interface
  BACKPORT: timer: convert timer_slack_ns from unsigned long to u64
  netfilter: xt_quota2: make quota2_log work well
  Revert "usb: gadget: prevent change of Host MAC address of 'usb0' interface"
  BACKPORT: PM / sleep: Go direct_complete if driver has no callbacks
  ANDROID: base-cfg: enable UID_CPUTIME
  UPSTREAM: USB: usbfs: fix potential infoleak in devio
  UPSTREAM: ALSA: timer: Fix leak in events via snd_timer_user_ccallback
  UPSTREAM: ALSA: timer: Fix leak in events via snd_timer_user_tinterrupt
  UPSTREAM: ALSA: timer: Fix leak in SNDRV_TIMER_IOCTL_PARAMS
  ANDROID: configs: remove unused configs
  ANDROID: cpu: send KOBJ_ONLINE event when enabling cpus
  ANDROID: dm verity fec: initialize recursion level
  ANDROID: dm verity fec: fix RS block calculation
  Linux 4.4.14
  netfilter: x_tables: introduce and use xt_copy_counters_from_user
  netfilter: x_tables: do compat validation via translate_table
  netfilter: x_tables: xt_compat_match_from_user doesn't need a retval
  netfilter: ip6_tables: simplify translate_compat_table args
  netfilter: ip_tables: simplify translate_compat_table args
  netfilter: arp_tables: simplify translate_compat_table args
  netfilter: x_tables: don't reject valid target size on some architectures
  netfilter: x_tables: validate all offsets and sizes in a rule
  netfilter: x_tables: check for bogus target offset
  netfilter: x_tables: check standard target size too
  netfilter: x_tables: add compat version of xt_check_entry_offsets
  netfilter: x_tables: assert minimum target size
  netfilter: x_tables: kill check_entry helper
  netfilter: x_tables: add and use xt_check_entry_offsets
  netfilter: x_tables: validate targets of jumps
  netfilter: x_tables: don't move to non-existent next rule
  drm/core: Do not preserve framebuffer on rmfb, v4.
  crypto: qat - fix adf_ctl_drv.c:undefined reference to adf_init_pf_wq
  netfilter: x_tables: fix unconditional helper
  netfilter: x_tables: make sure e->next_offset covers remaining blob size
  netfilter: x_tables: validate e->target_offset early
  MIPS: Fix 64k page support for 32 bit kernels.
  sparc64: Fix return from trap window fill crashes.
  sparc: Harden signal return frame checks.
  sparc64: Take ctx_alloc_lock properly in hugetlb_setup().
  sparc64: Reduce TLB flushes during hugepte changes
  sparc/PCI: Fix for panic while enabling SR-IOV
  sparc64: Fix sparc64_set_context stack handling.
  sparc64: Fix numa node distance initialization
  sparc64: Fix bootup regressions on some Kconfig combinations.
  sparc: Fix system call tracing register handling.
  fix d_walk()/non-delayed __d_free() race
  sched: panic on corrupted stack end
  proc: prevent stacking filesystems on top
  x86/entry/traps: Don't force in_interrupt() to return true in IST handlers
  wext: Fix 32 bit iwpriv compatibility issue with 64 bit Kernel
  ecryptfs: forbid opening files without mmap handler
  memcg: add RCU locking around css_for_each_descendant_pre() in memcg_offline_kmem()
  parisc: Fix pagefault crash in unaligned __get_user() call
  pinctrl: mediatek: fix dual-edge code defect
  powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call
  powerpc: Use privileged SPR number for MMCR2
  powerpc: Fix definition of SIAR and SDAR registers
  powerpc/pseries/eeh: Handle RTAS delay requests in configure_bridge
  arm64: mm: always take dirty state from new pte in ptep_set_access_flags
  arm64: Provide "model name" in /proc/cpuinfo for PER_LINUX32 tasks
  crypto: ccp - Fix AES XTS error for request sizes above 4096
  crypto: public_key: select CRYPTO_AKCIPHER
  irqchip/gic-v3: Fix ICC_SGI1R_EL1.INTID decoding mask
  s390/bpf: reduce maximum program size to 64 KB
  s390/bpf: fix recache skb->data/hlen for skb_vlan_push/pop
  gpio: bcm-kona: fix bcm_kona_gpio_reset() warnings
  ARM: fix PTRACE_SETVFPREGS on SMP systems
  ALSA: hda/realtek: Add T560 docking unit fixup
  ALSA: hda/realtek - Add support for new codecs ALC700/ALC701/ALC703
  ALSA: hda/realtek - ALC256 speaker noise issue
  ALSA: hda - Fix headset mic detection problem for Dell machine
  ALSA: hda - Add PCI ID for Kabylake
  KVM: irqfd: fix NULL pointer dereference in kvm_irq_map_gsi
  KVM: x86: fix OOPS after invalid KVM_SET_DEBUGREGS
  vxlan, gre, geneve: Set a large MTU on ovs-created tunnel devices
  geneve: Relax MTU constraints
  vxlan: Relax MTU constraints
  ipv6: Skip XFRM lookup if dst_entry in socket cache is valid
  l2tp: fix configuration passed to setup_udp_tunnel_sock()
  bridge: Don't insert unnecessary local fdb entry on changing mac address
  tcp: record TLP and ER timer stats in v6 stats
  vxlan: Accept user specified MTU value when create new vxlan link
  team: don't call netdev_change_features under team->lock
  sfc: on MC reset, clear PIO buffer linkage in TXQs
  bpf, inode: disallow userns mounts
  uapi glibc compat: fix compilation when !__USE_MISC in glibc
  udp: prevent skbs lingering in tunnel socket queues
  bpf: Use mount_nodev not mount_ns to mount the bpf filesystem
  tuntap: correctly wake up process during uninit
  switchdev: pass pointer to fib_info instead of copy
  tipc: fix nametable publication field in nl compat
  netlink: Fix dump skb leak/double free
  tipc: check nl sock before parsing nested attributes
  scsi: Add QEMU CD-ROM to VPD Inquiry Blacklist
  scsi_lib: correctly retry failed zero length REQ_TYPE_FS commands
  cs-etm: associating output packet with CPU they executed on
  cs-etm: removing unecessary structure field
  cs-etm: account for each trace buffer in the queue
  cs-etm: avoid casting variable
  perf tools: fixing Makefile problems
  perf tools: new naming convention for openCSD
  perf scripts: Add python scripts for CoreSight traces
  perf tools: decoding capailitity for CoreSight traces
  perf symbols: Check before overwriting build_id
  perf tools: pushing driver configuration down to the kernel
  perf tools: add infrastructure for PMU specific configuration
  coresight: etm-perf: incorporating sink definition from the cmd line
  coresight: adding sink parameter to function coresight_build_path()
  perf: passing struct perf_event to function setup_aux()
  perf/core: adding PMU driver specific configuration
  perf tools: adding coresight etm PMU record capabilities
  perf tools: making coresight PMU listable
  coresight: tmc: implementing TMC-ETR AUX space API
  coresight: Add support for Juno platform
  coresight: Handle build path error
  coresight: Fix erroneous memset in tmc_read_unprepare_etr
  coresight: Fix tmc_read_unprepare_etr
  coresight: Fix NULL pointer dereference in _coresight_build_path
  ANDROID: dm verity fec: add missing release from fec_ktype
  ANDROID: dm verity fec: limit error correction recursion
  ANDROID: restrict access to perf events
  FROMLIST: security,perf: Allow further restriction of perf_event_open
  BACKPORT: perf tools: Document the perf sysctls
  Revert "armv6 dcc tty driver"
  Revert "arm: dcc_tty: fix armv6 dcc tty build failure"
  ARM64: Ignore Image-dtb from git point of view
  arm64: add option to build Image-dtb
  ANDROID: usb: gadget: f_midi: set fi->f to NULL when free f_midi function
  Linux 4.4.13
  xfs: handle dquot buffer readahead in log recovery correctly
  xfs: print name of verifier if it fails
  xfs: skip stale inodes in xfs_iflush_cluster
  xfs: fix inode validity check in xfs_iflush_cluster
  xfs: xfs_iflush_cluster fails to abort on error
  xfs: Don't wrap growfs AGFL indexes
  xfs: disallow rw remount on fs with unknown ro-compat features
  gcov: disable tree-loop-im to reduce stack usage
  scripts/package/Makefile: rpmbuild add support of RPMOPTS
  dma-debug: avoid spinlock recursion when disabling dma-debug
  PM / sleep: Handle failures in device_suspend_late() consistently
  ext4: silence UBSAN in ext4_mb_init()
  ext4: address UBSAN warning in mb_find_order_for_block()
  ext4: fix oops on corrupted filesystem
  ext4: clean up error handling when orphan list is corrupted
  ext4: fix hang when processing corrupted orphaned inode list
  drm/imx: Match imx-ipuv3-crtc components using device node in platform data
  drm/i915: Don't leave old junk in ilk active watermarks on readout
  drm/atomic: Verify connector->funcs != NULL when clearing states
  drm/fb_helper: Fix references to dev->mode_config.num_connector
  drm/i915/fbdev: Fix num_connector references in intel_fb_initial_config()
  drm/amdgpu: Fix hdmi deep color support.
  drm/amdgpu: use drm_mode_vrefresh() rather than mode->vrefresh
  drm/vmwgfx: Fix order of operation
  drm/vmwgfx: use vmw_cmd_dx_cid_check for query commands.
  drm/vmwgfx: Enable SVGA_3D_CMD_DX_SET_PREDICATION
  drm/gma500: Fix possible out of bounds read
  sunrpc: fix stripping of padded MIC tokens
  xen: use same main loop for counting and remapping pages
  xen/events: Don't move disabled irqs
  powerpc/eeh: Restore initial state in eeh_pe_reset_and_recover()
  Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell"
  powerpc/eeh: Don't report error in eeh_pe_reset_and_recover()
  powerpc/book3s64: Fix branching to OOL handlers in relocatable kernel
  pipe: limit the per-user amount of pages allocated in pipes
  QE-UART: add "fsl,t1040-ucc-uart" to of_device_id
  wait/ptrace: assume __WALL if the child is traced
  mm: use phys_addr_t for reserve_bootmem_region() arguments
  media: v4l2-compat-ioctl32: fix missing reserved field copy in put_v4l2_create32
  PCI: Disable all BAR sizing for devices with non-compliant BARs
  pinctrl: exynos5440: Use off-stack memory for pinctrl_gpio_range
  clk: bcm2835: divider value has to be 1 or more
  clk: bcm2835: pll_off should only update CM_PLL_ANARST
  clk: at91: fix check of clk_register() returned value
  clk: bcm2835: Fix PLL poweron
  cpuidle: Fix cpuidle_state_is_coupled() argument in cpuidle_enter()
  cpuidle: Indicate when a device has been unregistered
  PM / Runtime: Fix error path in pm_runtime_force_resume()
  mfd: intel_soc_pmic_core: Terminate panel control GPIO lookup table correctly
  mfd: intel-lpss: Save register context on suspend
  hwmon: (ads7828) Enable internal reference
  aacraid: Fix for KDUMP driver hang
  aacraid: Fix for aac_command_thread hang
  aacraid: Relinquish CPU during timeout wait
  rtlwifi: pci: use dev_kfree_skb_irq instead of kfree_skb in rtl_pci_reset_trx_ring
  rtlwifi: Fix logic error in enter/exit power-save mode
  rtlwifi: btcoexist: Implement antenna selection
  rtlwifi: rtl8723be: Add antenna select module parameter
  hwrng: exynos - Fix unbalanced PM runtime put on timeout error path
  ath5k: Change led pin configuration for compaq c700 laptop
  ath10k: fix kernel panic, move arvifs list head init before htt init
  ath10k: fix rx_channel during hw reconfigure
  ath10k: fix firmware assert in monitor mode
  ath10k: fix debugfs pktlog_filter write
  ath9k: Fix LED polarity for some Mini PCI AR9220 MB92 cards.
  ath9k: Add a module parameter to invert LED polarity.
  ARM: dts: imx35: restore existing used clock enumeration
  ARM: dts: exynos: Add interrupt line to MAX8997 PMIC on exynos4210-trats
  ARM: dts: at91: fix typo in sama5d2 PIN_PD24 description
  ARM: mvebu: fix GPIO config on the Linksys boards
  Input: uinput - handle compat ioctl for UI_SET_PHYS
  ASoC: ak4642: Enable cache usage to fix crashes on resume
  affs: fix remount failure when there are no options changed
  MIPS: VDSO: Build with `-fno-strict-aliasing'
  MIPS: lib: Mark intrinsics notrace
  MIPS: Build microMIPS VDSO for microMIPS kernels
  MIPS: Fix sigreturn via VDSO on microMIPS kernel
  MIPS: ptrace: Prevent writes to read-only FCSR bits
  MIPS: ptrace: Fix FP context restoration FCSR regression
  MIPS: Disable preemption during prctl(PR_SET_FP_MODE, ...)
  MIPS: Prevent "restoration" of MSA context in non-MSA kernels
  MIPS: Fix MSA ld_*/st_* asm macros to use PTR_ADDU
  MIPS: Use copy_s.fmt rather than copy_u.fmt
  MIPS: Loongson-3: Reserve 32MB for RS780E integrated GPU
  MIPS: Reserve nosave data for hibernation
  MIPS: ath79: make bootconsole wait for both THRE and TEMT
  MIPS: Sync icache & dcache in set_pte_at
  MIPS: Handle highmem pages in __update_cache
  MIPS: Flush highmem pages in __flush_dcache_page
  MIPS: Fix watchpoint restoration
  MIPS: Fix uapi include in exported asm/siginfo.h
  MIPS: Fix siginfo.h to use strict posix types
  MIPS: Avoid using unwind_stack() with usermode
  MIPS: Don't unwind to user mode with EVA
  MIPS: MSA: Fix a link error on `_init_msa_upper' with older GCC
  MIPS: math-emu: Fix jalr emulation when rd == $0
  MIPS64: R6: R2 emulation bugfix
  coresight: etb10: adjust read pointer only when needed
  coresight: configuring ETF in FIFO mode when acting as link
  coresight: tmc: implementing TMC-ETF AUX space API
  coresight: moving struct cs_buffers to header file
  coresight: tmc: keep track of memory width
  coresight: tmc: make sysFS and Perf mode mutually exclusive
  coresight: tmc: dump system memory content only when needed
  coresight: tmc: adding mode of operation for link/sinks
  coresight: tmc: getting rid of multiple read access
  coresight: tmc: allocating memory when needed
  coresight: tmc: making prepare/unprepare functions generic
  coresight: tmc: splitting driver in ETB/ETF and ETR components
  coresight: tmc: cleaning up header file
  coresight: tmc: introducing new header file
  coresight: tmc: clearly define number of transfers per burst
  coresight: tmc: re-implementing tmc_read_prepare/unprepare() functions
  coresight: tmc: waiting for TMCReady bit before programming
  coresight: tmc: modifying naming convention
  coresight: tmc: adding sysFS management entries
  coresight: etm4x: add tracer ID for A72 Maia processor.
  coresight: etb10: fixing the right amount of words to read
  coresight: stm: adding driver for CoreSight STM component
  coresight: adding path for STM device
  coresight: etm4x: modify q_support type
  coresight: no need to do the forced type conversion
  coresight: removing gratuitous boot time log messages
  coresight: etb10: splitting sysFS "status" entry
  coresight: moving coresight_simple_func() to header file
  coresight: etm4x: implementing the perf PMU API
  coresight: etm4x: implementing user/kernel mode tracing
  coresight: etm4x: moving etm_drvdata::enable to atomic field
  coresight: etm4x: unlocking tracers in default arch init
  coresight: etm4x: splitting etmv4 default configuration
  coresight: etm4x: splitting struct etmv4_drvdata
  coresight: etm4x: adding config and traceid registers
  coresight: etm4x: moving sysFS entries to a dedicated file
  stm class: Support devices that override software assigned masters
  stm class: Remove unnecessary pointer increment
  stm class: Fix stm device initialization order
  stm class: Do not leak the chrdev in error path
  stm class: Remove a pointless line
  stm class: stm_heartbeat: Make nr_devs parameter read-only
  stm class: dummy_stm: Make nr_dummies parameter read-only
  MAINTAINERS: Add a git tree for the stm class
  perf/ring_buffer: Document AUX API usage
  perf/core: Free AUX pages in unmap path
  perf/ring_buffer: Refuse to begin AUX transaction after rb->aux_mmap_count drops
  perf auxtrace: Add perf_evlist pointer to *info_priv_size()
  perf session: Simplify tool stubs
  perf inject: Hit all DSOs for AUX data in JIT and other cases
  perf tools: tracepoint_error() can receive e=NULL, robustify it
  perf evlist: Make perf_evlist__open() open evsels with their cpus and threads (like perf record does)
  perf evsel: Introduce disable() method
  perf cpumap: Auto initialize cpu__max_{node,cpu}
  drivers/hwtracing: make coresight-etm-perf.c explicitly non-modular
  drivers/hwtracing: make coresight-* explicitly non-modular
  coresight: introducing a global trace ID function
  coresight: etm-perf: new PMU driver for ETM tracers
  coresight: etb10: implementing AUX API
  coresight: etb10: adding operation mode for sink->enable()
  coresight: etb10: moving to local atomic operations
  coresight: etm3x: implementing perf_enable/disable() API
  coresight: etm3x: implementing user/kernel mode tracing
  coresight: etm3x: consolidating initial config
  coresight: etm3x: changing default trace configuration
  coresight: etm3x: set progbit to stop trace collection
  coresight: etm3x: adding operation mode for etm_enable()
  coresight: etm3x: splitting struct etm_drvdata
  coresight: etm3x: unlocking tracers in default arch init
  coresight: etm3x: moving sysFS entries to dedicated file
  coresight: etm3x: moving etm_readl/writel to header file
  coresight: moving PM runtime operations to core framework
  coresight: add API to get sink from path
  coresight: associating path with session rather than tracer
  coresight: etm4x: Check every parameter used by dma_xx_coherent.
  coresight: "DEVICE_ATTR_RO" should defined as static.
  coresight: implementing 'cpu_id()' API
  coresight: removing bind/unbind options from sysfs
  coresight: remove csdev's link from topology
  coresight: release reference taken by 'bus_find_device()'
  coresight: coresight_unregister() function cleanup
  coresight: fixing lockdep error
  coresight: fixing indentation problem
  coresight: Fix a typo in Kconfig
  coresight: checking for NULL string in coresight_name_match()
  perf/core: Disable the event on a truncated AUX record
  perf/core: Don't leak event in the syscall error path
  perf/core: Fix perf_sched_count derailment
  stm class: dummy_stm: Add link callback for fault injection
  stm class: Plug stm device's unlink callback
  stm class: Fix a race in unlinking
  stm class: Fix unbalanced module/device refcounting
  stm class: Guard output assignment against concurrency
  stm class: Fix unlocking braino in the error path
  stm class: Add heartbeat stm source device
  stm class: dummy_stm: Create multiple devices
  stm class: Support devices with multiple instances
  stm class: Use driver's packet callback return value
  stm class: Prevent user-controllable allocations
  stm class: Fix link list locking
  stm class: Fix locking in unbinding policy path
  stm class: Select CONFIG_SRCU
  stm class: Hide STM-specific options if STM is disabled
  perf: Synchronously free aux pages in case of allocation failure
  Linux 4.4.12
  kbuild: move -Wunused-const-variable to W=1 warning level
  Revert "scsi: fix soft lockup in scsi_remove_target() on module removal"
  scsi: Add intermediate STARGET_REMOVE state to scsi_target_state
  hpfs: implement the show_options method
  hpfs: fix remount failure when there are no options changed
  UBI: Fix static volume checks when Fastmap is used
  SIGNAL: Move generic copy_siginfo() to signal.h
  thunderbolt: Fix double free of drom buffer
  IB/srp: Fix a debug kernel crash
  ALSA: hda - Fix headset mic detection problem for one Dell machine
  ALSA: hda/realtek - Add support for ALC295/ALC3254
  ALSA: hda - Fix headphone noise on Dell XPS 13 9360
  ALSA: hda/realtek - New codecs support for ALC234/ALC274/ALC294
  mcb: Fixed bar number assignment for the gdd
  clk: bcm2835: add locking to pll*_on/off methods
  locking,qspinlock: Fix spin_is_locked() and spin_unlock_wait()
  serial: samsung: Reorder the sequence of clock control when call s3c24xx_serial_set_termios()
  serial: 8250_mid: recognize interrupt source in handler
  serial: 8250_mid: use proper bar for DNV platform
  serial: 8250_pci: fix divide error bug if baud rate is 0
  Fix OpenSSH pty regression on close
  tty/serial: atmel: fix hardware handshake selection
  TTY: n_gsm, fix false positive WARN_ON
  tty: vt, return error when con_startup fails
  xen/x86: actually allocate legacy interrupts on PV guests
  KVM: x86: mask CPUID(0xD,0x1).EAX against host value
  MIPS: KVM: Fix timer IRQ race when writing CP0_Compare
  MIPS: KVM: Fix timer IRQ race when freezing timer
  KVM: x86: fix ordering of cr0 initialization code in vmx_cpu_reset
  KVM: MTRR: remove MSR 0x2f8
  staging: comedi: das1800: fix possible NULL dereference
  usb: gadget: udc: core: Fix argument of dev_err() in usb_gadget_map_request()
  USB: leave LPM alone if possible when binding/unbinding interface drivers
  usb: misc: usbtest: fix pattern tests for scatterlists.
  usb: f_mass_storage: test whether thread is running before starting another
  usb: gadget: f_fs: Fix EFAULT generation for async read operations
  USB: serial: option: add even more ZTE device ids
  USB: serial: option: add more ZTE device ids
  USB: serial: option: add support for Cinterion PH8 and AHxx
  USB: serial: io_edgeport: fix memory leaks in probe error path
  USB: serial: io_edgeport: fix memory leaks in attach error path
  USB: serial: quatech2: fix use-after-free in probe error path
  USB: serial: keyspan: fix use-after-free in probe error path
  USB: serial: mxuport: fix use-after-free in probe error path
  mei: bus: call mei_cl_read_start under device lock
  mei: amthif: discard not read messages
  mei: fix NULL dereferencing during FW initiated disconnection
  Bluetooth: vhci: Fix race at creating hci device
  Bluetooth: vhci: purge unhandled skbs
  Bluetooth: vhci: fix open_timeout vs. hdev race
  mmc: sdhci-pci: Remove MMC_CAP_BUS_WIDTH_TEST for Intel controllers
  mmc: longer timeout for long read time quirk
  dell-rbtn: Ignore ACPI notifications if device is suspended
  ACPI / osi: Fix an issue that acpi_osi=!* cannot disable ACPICA internal strings
  mmc: sdhci-acpi: Remove MMC_CAP_BUS_WIDTH_TEST for Intel controllers
  mmc: mmc: Fix partition switch timeout for some eMMCs
  can: fix handling of unmodifiable configuration options
  irqchip/gic-v3: Configure all interrupts as non-secure Group-1
  irqchip/gic: Ensure ordering between read of INTACK and shared data
  Input: pwm-beeper - fix - scheduling while atomic
  mfd: omap-usb-tll: Fix scheduling while atomic BUG
  sched/loadavg: Fix loadavg artifacts on fully idle and on fully loaded systems
  clk: qcom: msm8916: Fix crypto clock flags
  crypto: sun4i-ss - Replace spinlock_bh by spin_lock_irq{save|restore}
  crypto: talitos - fix ahash algorithms registration
  crypto: caam - fix caam_jr_alloc() ret code
  ring-buffer: Prevent overflow of size in ring_buffer_resize()
  ring-buffer: Use long for nr_pages to avoid overflow failures
  asix: Fix offset calculation in asix_rx_fixup() causing slow transmissions
  fs/cifs: correctly to anonymous authentication for the NTLM(v2) authentication
  fs/cifs: correctly to anonymous authentication for the NTLM(v1) authentication
  fs/cifs: correctly to anonymous authentication for the LANMAN authentication
  fs/cifs: correctly to anonymous authentication via NTLMSSP
  remove directory incorrectly tries to set delete on close on non-empty directories
  kvm: arm64: Fix EC field in inject_abt64
  arm/arm64: KVM: Enforce Break-Before-Make on Stage-2 page tables
  arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str
  arm64: Implement pmdp_set_access_flags() for hardware AF/DBM
  arm64: Implement ptep_set_access_flags() for hardware AF/DBM
  arm64: Ensure pmd_present() returns false after pmd_mknotpresent()
  arm64: Fix typo in the pmdp_huge_get_and_clear() definition
  ext4: iterate over buffer heads correctly in move_extent_per_page()
  perf test: Fix build of BPF and LLVM on older glibc libraries
  perf/core: Fix perf_event_open() vs. execve() race
  perf/x86/intel/pt: Generate PMI in the STOP region as well
  Btrfs: don't use src fd for printk
  UPSTREAM: mac80211: fix "warning: ‘target_metric’ may be used uninitialized"
  Revert "drivers: power: use 'current' instead of 'get_current()'"
  cpufreq: interactive: drop cpufreq_{get,put}_global_kobject func calls
  Revert "cpufreq: interactive: build fixes for 4.4"
  xt_qtaguid: Fix panic caused by processing non-full socket.
  fiq_debugger: Add fiq_debugger.disable option
  UPSTREAM: procfs: fixes pthread cross-thread naming if !PR_DUMPABLE
  FROMLIST: wlcore: Disable filtering in AP role
  Revert "drivers: power: Add watchdog timer to catch drivers which lockup during suspend."
  fiq_debugger: Add option to apply uart overlay by FIQ_DEBUGGER_UART_OVERLAY
  Revert "Recreate asm/mach/mmc.h include file"
  Revert "ARM: Add 'card_present' state to mmc_platfrom_data"
  usb: dual-role: make stub functions inline
  Revert "mmc: Add status IRQ and status callback function to mmc platform data"
  quick selinux support for tracefs
  Revert "hid-multitouch: Filter collections by application usage."
  Revert "HID: steelseries: validate output report details"
  xt_qtaguid: Fix panic caused by synack processing
  Revert "mm: vmscan: Add a debug file for shrinkers"
  Revert "SELinux: Enable setting security contexts on rootfs inodes."
  Revert "SELinux: build fix for 4.1"
  fuse: Add support for d_canonical_path
  vfs: change d_canonical_path to take two paths
  android: recommended.cfg: remove CONFIG_UID_STAT
  netfilter: xt_qtaguid: seq_printf fixes
  Revert "misc: uidstat: Adding uid stat driver to collect network statistics."
  Revert "net: activity_stats: Add statistics for network transmission activity"
  Revert "net: activity_stats: Stop using obsolete create_proc_read_entry api"
  Revert "misc: uidstat: avoid create_stat() race and blockage."
  Revert "misc: uidstat: Remove use of obsolete create_proc_read_entry api"
  Revert "misc seq_printf fixes for 4.4"
  Revert "misc: uid_stat: Include linux/atomic.h instead of asm/atomic.h"
  Revert "net: socket ioctl to reset connections matching local address"
  Revert "net: fix iterating over hashtable in tcp_nuke_addr()"
  Revert "net: fix crash in tcp_nuke_addr()"
  Revert "Don't kill IPv4 sockets when killing IPv6 sockets was requested."
  Revert "tcp: Fix IPV6 module build errors"
  android: base-cfg: remove CONFIG_SWITCH
  Revert "switch: switch class and GPIO drivers."
  Revert "drivers: switch: remove S_IWUSR from dev_attr"
  ANDROID: base-cfg: enable CONFIG_IP_NF_NAT
  BACKPORT: selinux: restrict kernel module loading
  android: base-cfg: enable CONFIG_QUOTA

Conflicts:
	Documentation/sysctl/kernel.txt
	drivers/cpufreq/cpufreq_interactive.c
	drivers/hwtracing/coresight/Kconfig
	drivers/hwtracing/coresight/Makefile
	drivers/hwtracing/coresight/coresight-etm4x.c
	drivers/hwtracing/coresight/coresight-etm4x.h
	drivers/hwtracing/coresight/coresight-priv.h
	drivers/hwtracing/coresight/coresight-stm.c
	drivers/hwtracing/coresight/coresight-tmc.c
	drivers/mmc/core/core.c
	include/linux/coresight-stm.h
	include/linux/coresight.h
	include/linux/msm_mdp.h
	include/uapi/linux/coresight-stm.h
	kernel/events/core.c
	kernel/sched/fair.c
	net/Makefile
	net/ipv4/netfilter/arp_tables.c
	net/ipv4/netfilter/ip_tables.c
	net/ipv4/tcp.c
	net/ipv6/netfilter/ip6_tables.c
	net/netfilter/xt_quota2.c
	sound/core/pcm.c

Change-Id: I17aa0002815014e9bddc47e67769a53c15768a99
Signed-off-by: Runmin Wang <runminw@codeaurora.org>
2016-10-28 10:48:35 -07:00
Olav Haugan
922fed628c timer: Do not require CPUSETS to be enabled for migration
Do not require CPUSETS to be enabled to allow migration of timers and
hrtimers.

Change-Id: Ib911a0d34c250c4df020bdb265b92d2b8df8db93
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:13 -07:00
Santosh Shukla
bba552f4fc timer: Add function to migrate timers
Add function to migrate timer that will be used by later patch set.

Change-Id: I370e404001344e635a663822b07557abbe0f6f52
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Updated commit text and fixed trivial merge conflict]
Git-commit: 3633b88d8fcb4273807574c27c328b6908a741e5
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:12 -07:00
Viresh Kumar
a7dffd7ffb timer: create timer_quiesce_cpu() to isolate CPU from timers
To isolate CPUs (isolate from timers) from sysfs using cpusets, we need some
support from the timer core. i.e. A routine timer_quiesce_cpu() which would
migrates away all the unpinned timers, but shouldn't touch the pinned ones.

This patch creates this routine.

Change-Id: I8624e0659b86b7b8fa425a3fafdb0784fe005124
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4. Fixes for compilation error]
Git-commit: 313910b70ea0c73f8789d9189c11e1f339080646
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:11 -07:00
Olav Haugan
6cc98f03ad timer: Ensure timers are not running before migrating
This is needed to support migration of timers during cpu isolation. A
timer might be running on the CPU that we want to isolate so we are
unable to migrate the timers at this point. We are adding a spin-loop to
wait for the timer to finish before migrating the timers.

Change-Id: I24d6e91b6dff468c640c2fe3a37a7f31b6f0c79a
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:11 -07:00
John Stultz
7584a50e33 BACKPORT: timer: convert timer_slack_ns from unsigned long to u64
This backports da8b44d5a9f8bf26da637b7336508ca534d6b319 from upstream.

This patchset introduces a /proc/<pid>/timerslack_ns interface which
would allow controlling processes to be able to set the timerslack value
on other processes in order to save power by avoiding wakeups (Something
Android currently does via out-of-tree patches).

The first patch tries to fix the internal timer_slack_ns usage which was
defined as a long, which limits the slack range to ~4 seconds on 32bit
systems.  It converts it to a u64, which provides the same basically
unlimited slack (500 years) on both 32bit and 64bit machines.

The second patch introduces the /proc/<pid>/timerslack_ns interface
which allows the full 64bit slack range for a task to be read or set on
both 32bit and 64bit machines.

With these two patches, on a 32bit machine, after setting the slack on
bash to 10 seconds:

$ time sleep 1

real    0m10.747s
user    0m0.001s
sys     0m0.005s

The first patch is a little ugly, since I had to chase the slack delta
arguments through a number of functions converting them to u64s.  Let me
know if it makes sense to break that up more or not.

Other than that things are fairly straightforward.

This patch (of 2):

The timer_slack_ns value in the task struct is currently a unsigned
long.  This means that on 32bit applications, the maximum slack is just
over 4 seconds.  However, on 64bit machines, its much much larger (~500
years).

This disparity could make application development a little (as well as
the default_slack) to a u64.  This means both 32bit and 64bit systems
have the same effective internal slack range.

Now the existing ABI via PR_GET_TIMERSLACK and PR_SET_TIMERSLACK specify
the interface as a unsigned long, so we preserve that limitation on
32bit systems, where SET_TIMERSLACK can only set the slack to a unsigned
long value, and GET_TIMERSLACK will return ULONG_MAX if the slack is
actually larger then what can be stored by an unsigned long.

This patch also modifies hrtimer functions which specified the slack
delta as a unsigned long.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oren Laadan <orenl@cellrox.com>
Cc: Ruchi Kandoi <kandoiruchi@google.com>
Cc: Rom Lemarchand <romlem@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-11 12:43:04 +05:30
Joonwoo Park
646bf5125d timer: make deferrable cpu unbound timers really not bound to a cpu
When a deferrable work (INIT_DEFERRABLE_WORK, etc.) is queued via
queue_delayed_work() it's probably intended to run the work item on any
CPU that isn't idle. However, we queue the work to run at a later time
by starting a deferrable timer that binds to whatever CPU the work is
queued on which is same with queue_delayed_work_on(smp_processor_id())
effectively.

As a result WORK_CPU_UNBOUND work items aren't really cpu unbound now.
In fact this is perfectly fine with UP kernel and also won't affect much a
system without dyntick with SMP kernel too as every cpus run timers
periodically.  But on SMP systems with dyntick current implementation leads
deferrable timers not very scalable because the timer's base which has
queued the deferrable timer won't wake up till next non-deferrable timer
expires even though there are possible other non idle cpus are running
which are able to run expired deferrable timers.

The deferrable work is a good example of the current implementation's
victim like below.

INIT_DEFERRABLE_WORK(&dwork, fn);
CPU 0                                 CPU 1
queue_delayed_work(wq, &dwork, HZ);
    queue_delayed_work_on(WORK_CPU_UNBOUND);
        ...
	__mod_timer() -> queues timer to the
			 current cpu's timer
			 base.
	...
tick_nohz_idle_enter() -> cpu enters idle.
A second later
cpu 0 is now in idle.                 cpu 1 exits idle or wasn't in idle so
                                      now it's in active but won't
cpu 0 won't wake up till next         handle cpu unbound deferrable timer
non-deferrable timer expires.         as it's in cpu 0's timer base.

To make all cpu unbound deferrable timers are scalable, introduce a common
timer base which is only for cpu unbound deferrable timers to make those
are indeed cpu unbound so that can be scheduled by tick_do_timer_cpu.
This common timer fixes scalability issue of delayed work and all other cpu
unbound deferrable timer using implementations.

Change-Id: I8b6c57d8b6445a76fa02a8cb598a8ef22aef7200
CC: Thomas Gleixner <tglx@linutronix.de>
CC: John Stultz <john.stultz@linaro.org>
CC: Tejun Heo <tj@kernel.org>
[joonwoop@codeaurora.org: timer->base replaced with CPU index so get
 the deferrable timer wheel from lock_timer_base() instead of
 do_init_timer().]
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
2016-03-23 21:10:48 -07:00
Tejun Heo
22b886dd10 timers: Use proper base migration in add_timer_on()
Regardless of the previous CPU a timer was on, add_timer_on()
currently simply sets timer->flags to the new CPU.  As the caller must
be seeing the timer as idle, this is locally fine, but the timer
leaving the old base while unlocked can lead to race conditions as
follows.

Let's say timer was on cpu 0.

  cpu 0					cpu 1
  -----------------------------------------------------------------------------
  del_timer(timer) succeeds
					del_timer(timer)
					  lock_timer_base(timer) locks cpu_0_base
  add_timer_on(timer, 1)
    spin_lock(&cpu_1_base->lock)
    timer->flags set to cpu_1_base
    operates on @timer			  operates on @timer

This triggered with mod_delayed_work_on() which contains
"if (del_timer()) add_timer_on()" sequence eventually leading to the
following oops.

  BUG: unable to handle kernel NULL pointer dereference at           (null)
  IP: [<ffffffff810ca6e9>] detach_if_pending+0x69/0x1a0
  ...
  Workqueue: wqthrash wqthrash_workfunc [wqthrash]
  task: ffff8800172ca680 ti: ffff8800172d0000 task.ti: ffff8800172d0000
  RIP: 0010:[<ffffffff810ca6e9>]  [<ffffffff810ca6e9>] detach_if_pending+0x69/0x1a0
  ...
  Call Trace:
   [<ffffffff810cb0b4>] del_timer+0x44/0x60
   [<ffffffff8106e836>] try_to_grab_pending+0xb6/0x160
   [<ffffffff8106e913>] mod_delayed_work_on+0x33/0x80
   [<ffffffffa0000081>] wqthrash_workfunc+0x61/0x90 [wqthrash]
   [<ffffffff8106dba8>] process_one_work+0x1e8/0x650
   [<ffffffff8106e05e>] worker_thread+0x4e/0x450
   [<ffffffff810746af>] kthread+0xef/0x110
   [<ffffffff8185980f>] ret_from_fork+0x3f/0x70

Fix it by updating add_timer_on() to perform proper migration as
__mod_timer() does.

Reported-and-tested-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Worley <chris.worley@primarydata.com>
Cc: bfields@fieldses.org
Cc: Michael Skralivetsky <michael.skralivetsky@primarydata.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: kernel-team@fb.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20151029103113.2f893924@tlielax.poochiereds.net
Link: http://lkml.kernel.org/r/20151104171533.GI5749@mtj.duckdns.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-11-04 20:23:19 +01:00
Rasmus Villemoes
9fc4468d54 timers: Use __fls in apply_slack()
In apply_slack(), find_last_bit() is applied to a bitmask consisting
of precisely BITS_PER_LONG bits. Since mask is non-zero, we might as
well eliminate the function call and use __fls() directly. On x86_64,
this shaves 23 bytes of the only caller, mod_timer().

This also gets rid of Coverity CID 1192106, but that is a false
positive: Coverity is not aware that mask != 0 implies that
find_last_bit will not return BITS_PER_LONG.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1443771931-6284-1-git-send-email-linux@rasmusvillemoes.dk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-11 22:13:46 +02:00
Dmitry Vyukov
3ed769bdb2 timers: Fix data race in timer_stats_account_timer()
timer_stats_account_timer() reads timer->start_site, then checks it
for NULL and then re-reads it again, while
timer_stats_timer_clear_start_info() can concurrently reset
timer->start_site to NULL. This should not lead to crashes, but can
double number of entries in timer stats as start_site is used during
comparison, the doubled entries will have unuseful NULL start_site.

Read timer->start_site only once in timer_stats_account_timer().

The data race was found with KernelThreadSanitizer (KTSAN).

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: andreyknvl@google.com
Cc: glider@google.com
Cc: kcc@google.com
Cc: ktsan@googlegroups.com
Cc: john.stultz@linaro.org
Link: http://lkml.kernel.org/r/1442584463-69553-1-git-send-email-dvyukov@google.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-22 15:43:18 +02:00
Eric Dumazet
d0023a1448 timer: Write timer->flags atomically
lock_timer_base() cannot prevent the following :

CPU1 ( in __mod_timer()
timer->flags |= TIMER_MIGRATING;
spin_unlock(&base->lock);
base = new_base;
spin_lock(&base->lock);
// The next line clears TIMER_MIGRATING
timer->flags &= ~TIMER_BASEMASK;
                                  CPU2 (in lock_timer_base())
                                  see timer base is cpu0 base
                                  spin_lock_irqsave(&base->lock, *flags);
                                  if (timer->flags == tf)
                                       return base; // oops, wrong base
timer->flags |= base->cpu // too late

We must write timer->flags in one go, otherwise we can fool other cpus.

Fixes: bc7a34b8b9 ("timer: Reduce timer migration overhead if disabled")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jon Christopherson <jon@jons.org>
Cc: David Miller <davem@davemloft.net>
Cc: xen-devel@lists.xen.org
Cc: david.vrabel@citrix.com
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Link: http://lkml.kernel.org/r/1439831928.32680.11.camel@edumazet-glaptop2.roam.corp.google.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
2015-08-18 15:31:16 +02:00
Thomas Gleixner
24bfcb1009 timer: Fix hotplug regression
The recent timer wheel rework removed the get/put_cpu_var() pair in
the hotplug migration code, which results in:

BUG: using smp_processor_id() in preemptible [00000000] code: hib.sh/2845
...
[<ffffffff810d4fa3>] timer_cpu_notify+0x53/0x12

That hunk is a leftover from an earlier iteration and went unnoticed
so far.

Restore the previous code which was obviously correct.

Fixes: 0eeda71bc3 'timer: Replace timer base by a cpu index'
Reported-and_tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-26 22:58:06 +02:00
Thomas Gleixner
683be13a28 timer: Minimize nohz off overhead
If nohz is disabled on the kernel command line the [hr]timer code
still calls wake_up_nohz_cpu() and tick_nohz_full_cpu(), a pretty
pointless exercise. Cache nohz_active in [hr]timer per cpu bases and
avoid the overhead.

Before:
  48.10%  hog       [.] main
  15.25%  [kernel]  [k] _raw_spin_lock_irqsave
   9.76%  [kernel]  [k] _raw_spin_unlock_irqrestore
   6.50%  [kernel]  [k] mod_timer
   6.44%  [kernel]  [k] lock_timer_base.isra.38
   3.87%  [kernel]  [k] detach_if_pending
   3.80%  [kernel]  [k] del_timer
   2.67%  [kernel]  [k] internal_add_timer
   1.33%  [kernel]  [k] __internal_add_timer
   0.73%  [kernel]  [k] timerfn
   0.54%  [kernel]  [k] wake_up_nohz_cpu

After:
  48.73%  hog       [.] main
  15.36%  [kernel]  [k] _raw_spin_lock_irqsave
   9.77%  [kernel]  [k] _raw_spin_unlock_irqrestore
   6.61%  [kernel]  [k] lock_timer_base.isra.38
   6.42%  [kernel]  [k] mod_timer
   3.90%  [kernel]  [k] detach_if_pending
   3.76%  [kernel]  [k] del_timer
   2.41%  [kernel]  [k] internal_add_timer
   1.39%  [kernel]  [k] __internal_add_timer
   0.76%  [kernel]  [k] timerfn

We probably should have a cached value for nohz full in the per cpu
bases as well to avoid the cpumask check. The base cache line is hot
already, the cpumask not necessarily.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Link: http://lkml.kernel.org/r/20150526224512.207378134@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:28 +02:00
Thomas Gleixner
bc7a34b8b9 timer: Reduce timer migration overhead if disabled
Eric reported that the timer_migration sysctl is not really nice
performance wise as it needs to check at every timer insertion whether
the feature is enabled or not. Further the check does not live in the
timer code, so we have an extra function call which checks an extra
cache line to figure out that it is disabled.

We can do better and store that information in the per cpu (hr)timer
bases. I pondered to use a static key, but that's a nightmare to
update from the nohz code and the timer base cache line is hot anyway
when we select a timer base.

The old logic enabled the timer migration unconditionally if
CONFIG_NO_HZ was set even if nohz was disabled on the kernel command
line.

With this modification, we start off with migration disabled. The user
visible sysctl is still set to enabled. If the kernel switches to NOHZ
migration is enabled, if the user did not disable it via the sysctl
prior to the switch. If nohz=off is on the kernel command line,
migration stays disabled no matter what.

Before:
  47.76%  hog       [.] main
  14.84%  [kernel]  [k] _raw_spin_lock_irqsave
   9.55%  [kernel]  [k] _raw_spin_unlock_irqrestore
   6.71%  [kernel]  [k] mod_timer
   6.24%  [kernel]  [k] lock_timer_base.isra.38
   3.76%  [kernel]  [k] detach_if_pending
   3.71%  [kernel]  [k] del_timer
   2.50%  [kernel]  [k] internal_add_timer
   1.51%  [kernel]  [k] get_nohz_timer_target
   1.28%  [kernel]  [k] __internal_add_timer
   0.78%  [kernel]  [k] timerfn
   0.48%  [kernel]  [k] wake_up_nohz_cpu

After:
  48.10%  hog       [.] main
  15.25%  [kernel]  [k] _raw_spin_lock_irqsave
   9.76%  [kernel]  [k] _raw_spin_unlock_irqrestore
   6.50%  [kernel]  [k] mod_timer
   6.44%  [kernel]  [k] lock_timer_base.isra.38
   3.87%  [kernel]  [k] detach_if_pending
   3.80%  [kernel]  [k] del_timer
   2.67%  [kernel]  [k] internal_add_timer
   1.33%  [kernel]  [k] __internal_add_timer
   0.73%  [kernel]  [k] timerfn
   0.54%  [kernel]  [k] wake_up_nohz_cpu


Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Link: http://lkml.kernel.org/r/20150526224512.127050787@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:28 +02:00
Thomas Gleixner
c74441a17e timer: Stats: Simplify the flags handling
Simplify the handling of the flag storage for the timer statistics. No
intermediate storage anymore. Just hand over the flags field.

I left the printout of 'deferrable' for now because changing this
would be an ABI update and I have no idea how strong people feel about
that. OTOH, I wonder whether we should kill the whole timer stats
stuff because all of that information can be retrieved via ftrace/perf
as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Link: http://lkml.kernel.org/r/20150526224512.046626248@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:27 +02:00
Thomas Gleixner
0eeda71bc3 timer: Replace timer base by a cpu index
Instead of storing a pointer to the per cpu tvec_base we can simply
cache a CPU index in the timer_list and use that to get hold of the
correct per cpu tvec_base. This is only used in lock_timer_base() and
the slightly larger code is peanuts versus the spinlock operation and
the d-cache foot print of the timer wheel.

Aside of that this allows to get rid of following nuisances:

 - boot_tvec_base

   That statically allocated 4k bss data is just kept around so the
   timer has a home when it gets statically initialized. It serves no
   other purpose.

   With the CPU index we assign the timer to CPU0 at static
   initialization time and therefor can avoid the whole boot_tvec_base
   dance.  That also simplifies the init code, which just can use the
   per cpu base.

   Before:
     text	   data	    bss	    dec	    hex	filename
    17491	   9201	   4160	  30852	   7884	../build/kernel/time/timer.o
   After:
     text	   data	    bss	    dec	    hex	filename
    17440	   9193	      0	  26633	   6809	../build/kernel/time/timer.o

 - Overloading the base pointer with various flags

   The CPU index has enough space to hold the flags (deferrable,
   irqsafe) so we can get rid of the extra masking and bit fiddling
   with the base pointer.

As a benefit we reduce the size of struct timer_list on 64 bit
machines. 4 - 8 bytes, a size reduction up to 15% per struct timer_list,
which is a real win as we have tons of them embedded in other structs.

This changes also the newly added deferrable printout of the timer
start trace point to capture and print all timer->flags, which allows
us to decode the target cpu of the timer as well.

We might have used bitfields for this, but that would change the
static initializers and the init function for no value to accomodate
big endian bitfields.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Badhri Jagan Sridharan <Badhri@google.com>
Link: http://lkml.kernel.org/r/20150526224511.950084301@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:27 +02:00
Thomas Gleixner
1dabbcec2c timer: Use hlist for the timer wheel hash buckets
This reduces the size of struct tvec_base by 50% and results in
slightly smaller code as well.

Before:
   struct tvec_base: size: 8256, cachelines: 129

   text	   data	    bss	    dec	    hex	filename
  17698	  13297	   8256	  39251	   9953	../build/kernel/time/timer.o

After:
  struct tvec_base: 4160, cachelines: 65

   text	   data	    bss	    dec	    hex	filename
  17491	   9201	   4160	  30852	   7884	../build/kernel/time/timer.o

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Link: http://lkml.kernel.org/r/20150526224511.854731214@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:27 +02:00
Thomas Gleixner
1bd04bf6f6 timer: Remove FIFO "guarantee"
The FIFO guarantee is only there if two timers are queued into the
same bucket at the same jiffie on the same cpu:

 - The slack value depends on the delta between expiry and enqueue
   time, so the resulting expiry time can be different for timers
   which are queued in different jiffies.

 - Timers which are queued into the secondary array end up after a
   later queued timer which was queued into the primary array due to
   cascading.

 - Timers can end up on different cpus due to the NOHZ target moving
   around. Obviously there is no guarantee of expiry ordering between
   cpus.

So anything which relies on FIFO behaviour of the timer wheel is
broken already.

This is a preparatory patch for converting the timer wheel to hlist
which reduces the memory foot print of the wheel by 50%.

It's a seperate patch so any (unlikely to happen) regression caused by
this can be identified clearly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Cc: George Spelvin <linux@horizon.com>
Link: http://lkml.kernel.org/r/20150526224511.757520403@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:27 +02:00
Thomas Gleixner
3bb475a344 timers: Sanitize catchup_timer_jiffies() usage
catchup_timer_jiffies() has been applied blindly to several functions
without looking for possible better ways to do it.

1) internal_add_timer()

   Move the update to base->all_timers before we actually insert the
   timer into the wheel.

2) detach_if_pending()

   Again the update to base->all_timers allows us to explicitely do
   the timer_jiffies update in place, if this was the last timer which
   got removed.

3) __run_timers()

   We only check on entry, which is silly, because base->timer_jiffies
   can be behind - especially on NOHZ kernels - and if there is a
   single deferrable timer somewhere between base->timer_jiffies and
   jiffies we expire it and then loop until base->timer_jiffies ==
   jiffies.

   Move it into the loop.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joonwoo Park <joonwoop@codeaurora.org>
Cc: Wenbo Wang <wenbo.wang@memblaze.com>
Link: http://lkml.kernel.org/r/20150526224511.662994644@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 15:18:27 +02:00
Badhri Jagan Sridharan
4e413e8526 tracing: timer: Add deferrable flag to timer_start
The timer_start event now shows whether the timer is
deferrable in case of a low-res timer. The debug_activate
function now includes a deferrable flag while calling
the trace_timer_start event.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com>
[jstultz: Fixed minor whitespace and grammer tweaks
 pointed out by Ingo]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-22 10:36:06 -07:00
Joonwoo Park
781978e6e1 timer: Use timer->base for flag checks
At present, internal_add_timer() examines flags with 'base' which doesn't
contain flags.  Examine with 'timer->base' to avoid unnecessary waking up
of nohz CPU when timer base has TIMER_DEFERRABLE set.

Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Cc: sboyd@codeaurora.org
Cc: skannan@codeaurora.org
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1430187709-21087-1-git-send-email-joonwoop@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-05 10:40:43 +02:00
Thomas Gleixner
2ad5d3272d timer: Put usleep_range into the __sched section
do_usleep_range() and schedule_hrtimeout_range() are __sched as
well. So it makes no sense to have the exported function in a
different section.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20150414203503.833709502@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-22 17:06:52 +02:00
Thomas Gleixner
6deba083e1 timer: Remove pointless return value of do_usleep_range()
The only user ignores it anyway and rightfully so.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20150414203503.756060258@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-22 17:06:52 +02:00
Thomas Gleixner
c1ad348b45 tick: Nohz: Rework next timer evaluation
The evaluation of the next timer in the nohz code is based on jiffies
while all the tick internals are nano seconds based. We have also to
convert hrtimer nanoseconds to jiffies in the !highres case. That's
just wrong and introduces interesting corner cases.

Turn it around and convert the next timer wheel timer expiry and the
rcu event to clock monotonic and base all calculations on
nanoseconds. That identifies the case where no timer is pending
clearly with an absolute expiry value of KTIME_MAX.

Makes the code more readable and gets rid of the jiffies magic in the
nohz code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Link: http://lkml.kernel.org/r/20150414203502.184198593@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-22 17:06:50 +02:00
Thomas Gleixner
c6eb3f70d4 hrtimer: Get rid of hrtimer softirq
hrtimer softirq is a leftover from the initial implementation and
serves only the purpose to handle the enqueueing of already expired
timers in the high resolution timer mode. We discussed whether we
change the return value and force all start sites to handle that the
timer is already expired, but that would be a Herculean task and I'm
not sure whether its a good idea to enforce that handling on
everyone.

A simpler solution is to enforce a timer interrupt instead of raising
and scheduling a softirq. Just use the existing infrastructure to do
so and remove all the softirq leftovers.

The HRTIMER softirq enum is now unused, but kept around because trace
parsers rely on the existing numbering.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20150414203501.840834708@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-04-22 17:06:50 +02:00
Peter Zijlstra
3650b57fdf timer: Further simplify the SMP and HOTPLUG logic
Remove one CONFIG_HOTPLUG_CPU #ifdef in trade for introducing one
CONFIG_SMP #ifdef.

The CONFIG_SMP ifdef avoids declaring the per-CPU __tvec_bases storage
on UP systems since they already have boot_tvec_bases.

Also (re)add a runtime check on the base alignment -- for the paranoid
amongst us :-)

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fdd2d35e169bdc554ffa3fe77f77716298c75ada.1427814611.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-02 17:46:21 +02:00
Viresh Kumar
8def906044 timer: Don't initialize 'tvec_base' on hotplug
There is no need to call init_timers_cpu() on every CPU hotplug event,
there is not much we need to reset.

 - Timer-lists are already empty at the end of migrate_timers().
 - timer_jiffies will be refreshed while adding a new timer, after the
   CPU is online again.
 - active_timers and all_timers can be reset from migrate_timers().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/54a1c30ea7b805af55beb220cadf5a07a21b0a4d.1427814611.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-02 17:46:01 +02:00
Peter Zijlstra
b337a9380f timer: Allocate per-cpu tvec_base's statically
Memory for the 'tvec_base' array is allocated separately for the boot CPU (statically)
and non-boot CPUs (dynamically).

The reason is because __TIMER_INITIALIZER() needs to set ->base to a
valid pointer (because we've made NULL special, hint: lock_timer_base())
and we cannot get a compile time pointer to per-cpu entries because we
don't know where we'll map the section, even for the boot cpu.

This can be simplified a bit by statically allocating per-cpu memory.
The only disadvantage is that memory for one of the structures will stay
unused, i.e. for the boot CPU, which uses boot_tvec_bases.

This will also guarantee that tvec_base is cacheline aligned. Even
though tvec_base has ____cacheline_aligned stuck on, kzalloc_node() does
not actually respect that (but guarantees a minimum u64 alignment).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/17cdf560f2727f687ab159707d0aa591f8a2f82d.1427814611.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-02 17:46:00 +02:00
Paul E. McKenney
c3377c2da6 rcu: Remove "cpu" argument to rcu_check_callbacks()
The "cpu" argument was kept around on the off-chance that RCU might
offload scheduler-clock interrupts.  However, this offload approach
has been replaced by NO_HZ_FULL, which offloads -all- RCU processing
from qualifying CPUs.  It is therefore time to remove the "cpu" argument
to rcu_check_callbacks(), which this commit does.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:11 -08:00
Linus Torvalds
0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Frederic Weisbecker
76a33061b9 irq_work: Force raised irq work to run on irq work interrupt
The nohz full kick, which restarts the tick when any resource depend
on it, can't be executed anywhere given the operation it does on timers.
If it is called from the scheduler or timers code, chances are that
we run into a deadlock.

This is why we run the nohz full kick from an irq work. That way we make
sure that the kick runs on a virgin context.

However if that's the case when irq work runs in its own dedicated
self-ipi, things are different for the big bunch of archs that don't
support the self triggered way. In order to support them, irq works are
also handled by the timer interrupt as fallback.

Now when irq works run on the timer interrupt, the context isn't blank.
More precisely, they can run in the context of the hrtimer that runs the
tick. But the nohz kick cancels and restarts this hrtimer and cancelling
an hrtimer from itself isn't allowed. This is why we run in an endless
loop:

	Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 2
	CPU: 2 PID: 7538 Comm: kworker/u8:8 Not tainted 3.16.0+ #34
	Workqueue: btrfs-endio-write normal_work_helper [btrfs]
	 ffff880244c06c88 000000001b486fe1 ffff880244c06bf0 ffffffff8a7f1e37
	 ffffffff8ac52a18 ffff880244c06c78 ffffffff8a7ef928 0000000000000010
	 ffff880244c06c88 ffff880244c06c20 000000001b486fe1 0000000000000000
	Call Trace:
	 <NMI[<ffffffff8a7f1e37>] dump_stack+0x4e/0x7a
	 [<ffffffff8a7ef928>] panic+0xd4/0x207
	 [<ffffffff8a1450e8>] watchdog_overflow_callback+0x118/0x120
	 [<ffffffff8a186b0e>] __perf_event_overflow+0xae/0x350
	 [<ffffffff8a184f80>] ? perf_event_task_disable+0xa0/0xa0
	 [<ffffffff8a01a4cf>] ? x86_perf_event_set_period+0xbf/0x150
	 [<ffffffff8a187934>] perf_event_overflow+0x14/0x20
	 [<ffffffff8a020386>] intel_pmu_handle_irq+0x206/0x410
	 [<ffffffff8a01937b>] perf_event_nmi_handler+0x2b/0x50
	 [<ffffffff8a007b72>] nmi_handle+0xd2/0x390
	 [<ffffffff8a007aa5>] ? nmi_handle+0x5/0x390
	 [<ffffffff8a0cb7f8>] ? match_held_lock+0x8/0x1b0
	 [<ffffffff8a008062>] default_do_nmi+0x72/0x1c0
	 [<ffffffff8a008268>] do_nmi+0xb8/0x100
	 [<ffffffff8a7ff66a>] end_repeat_nmi+0x1e/0x2e
	 [<ffffffff8a0cb7f8>] ? match_held_lock+0x8/0x1b0
	 [<ffffffff8a0cb7f8>] ? match_held_lock+0x8/0x1b0
	 [<ffffffff8a0cb7f8>] ? match_held_lock+0x8/0x1b0
	 <<EOE><IRQ[<ffffffff8a0ccd2f>] lock_acquired+0xaf/0x450
	 [<ffffffff8a0f74c5>] ? lock_hrtimer_base.isra.20+0x25/0x50
	 [<ffffffff8a7fc678>] _raw_spin_lock_irqsave+0x78/0x90
	 [<ffffffff8a0f74c5>] ? lock_hrtimer_base.isra.20+0x25/0x50
	 [<ffffffff8a0f74c5>] lock_hrtimer_base.isra.20+0x25/0x50
	 [<ffffffff8a0f7723>] hrtimer_try_to_cancel+0x33/0x1e0
	 [<ffffffff8a0f78ea>] hrtimer_cancel+0x1a/0x30
	 [<ffffffff8a109237>] tick_nohz_restart+0x17/0x90
	 [<ffffffff8a10a213>] __tick_nohz_full_check+0xc3/0x100
	 [<ffffffff8a10a25e>] nohz_full_kick_work_func+0xe/0x10
	 [<ffffffff8a17c884>] irq_work_run_list+0x44/0x70
	 [<ffffffff8a17c8da>] irq_work_run+0x2a/0x50
	 [<ffffffff8a0f700b>] update_process_times+0x5b/0x70
	 [<ffffffff8a109005>] tick_sched_handle.isra.21+0x25/0x60
	 [<ffffffff8a109b81>] tick_sched_timer+0x41/0x60
	 [<ffffffff8a0f7aa2>] __run_hrtimer+0x72/0x470
	 [<ffffffff8a109b40>] ? tick_sched_do_timer+0xb0/0xb0
	 [<ffffffff8a0f8707>] hrtimer_interrupt+0x117/0x270
	 [<ffffffff8a034357>] local_apic_timer_interrupt+0x37/0x60
	 [<ffffffff8a80010f>] smp_apic_timer_interrupt+0x3f/0x50
	 [<ffffffff8a7fe52f>] apic_timer_interrupt+0x6f/0x80

To fix this we force non-lazy irq works to run on irq work self-IPIs
when available. That ability of the arch to trigger irq work self IPIs
is available with arch_irq_work_has_interrupt().

Reported-by: Catalin Iacob <iacobcatalin@gmail.com>
Reported-by: Dave Jones <davej@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-09-13 18:38:15 +02:00
Christoph Lameter
22127e93c5 time: Replace __get_cpu_var uses
Convert uses of __get_cpu_var for creating a address from a percpu
offset to this_cpu_ptr.

The two cases where get_cpu_var is used to actually access a percpu
variable are changed to use this_cpu_read/raw_cpu_read.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:44 -04:00
Viresh Kumar
9f6d9baaa8 timer: Kick dynticks targets on mod_timer*() calls
When a timer is enqueued or modified on a dynticks target, that CPU
must re-evaluate the next tick to service that timer.

The tick re-evaluation is performed by an IPI kick on the target.
Now while we correctly call wake_up_nohz_cpu() from add_timer_on(), the
mod_timer*() API family doesn't support so well dynticks targets.

The reason for this is likely that __mod_timer() isn't supposed to
select an idle target for a timer, unless that target is the current
CPU, in which case a dynticks idle kick isn't actually needed.

But there is a small race window lurking behind that assumption: the
elected target has all the time to turn dynticks idle between the call
to get_nohz_timer_target() and the locking of its base. Hence a risk
that we enqueue a timer on a dynticks idle destination without kicking
it. As a result, the timer might be serviced too late in the future.

Also a target elected by __mod_timer() can be in full dynticks mode
and thus require to be kicked as well. And unlike idle dynticks, this
concern both local and remote targets.

To fix this whole issue, lets centralize the dynticks kick to
internal_add_timer() so that it is well handled for all sort of timer
enqueue. Even timer migration is concerned so that a full dynticks target
is correctly kicked as needed when timers are migrating to it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1403393357-2070-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-06-23 11:23:47 +02:00
Viresh Kumar
d6f9382981 timer: Store cpu-number in struct tvec_base
Timers are serviced by the tick. But when a timer is enqueued on a
dynticks target, we need to kick it in order to make it reconsider the
next tick to schedule to correctly handle the timer's expiring time.

Now while this kick is correctly performed for add_timer_on(), the
mod_timer*() family has been a bit neglected.

To prepare for fixing this, we need internal_add_timer() to be able to
resolve the CPU target associated to a timer's object 'base' so that the
kick can be centralized there.

This can't be passed as an argument as not all the callers know the CPU
number of a timer's base. So lets store it in the struct tvec_base to
resolve the CPU without much overhead. It is set once for good at every
CPU's first boot.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1403393357-2070-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-06-23 11:23:46 +02:00
Thomas Gleixner
5cee964597 time/timers: Move all time(r) related files into kernel/time
Except for Kconfig.HZ. That needs a separate treatment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-06-23 11:22:35 +02:00
Renamed from kernel/timer.c (Browse further)