Commit Graph

1421 Commits

Author SHA1 Message Date
Mel Gorman 4248b0da46 fs, file table: reinit files_stat.max_files after deferred memory initialisation
Dave Hansen reported the following;

	My laptop has been behaving strangely with 4.2-rc2.  Once I log
	in to my X session, I start getting all kinds of strange errors
	from applications and see this in my dmesg:

        	VFS: file-max limit 8192 reached

The problem is that the file-max is calculated before memory is fully
initialised and miscalculates how much memory the kernel is using.  This
patch recalculates file-max after deferred memory initialisation.  Note
that using memory hotplug infrastructure would not have avoided this
problem as the value is not recalculated after memory hot-add.

4.1:             files_stat.max_files = 6582781
4.2-rc2:         files_stat.max_files = 8192
4.2-rc2 patched: files_stat.max_files = 6562467

Small differences with the patch applied and 4.1 but not enough to matter.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Dave Hansen <dave.hansen@intel.com>
Cc: Nicolai Stange <nicstange@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Alex Ng <alexng@microsoft.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-07 04:39:40 +03:00
Linus Torvalds 22a093b2fb Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Debug info and other statistics fixes and related enhancements"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Fix numa balancing stats in /proc/pid/sched
  sched/numa: Show numa_group ID in /proc/sched_debug task listings
  sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h
  sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y
  sched/stat: Simplify the sched_info accounting dependency
2015-07-04 08:56:53 -07:00
Linus Torvalds 91cca0f0ff Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull max log buf size increase from Ingo Molnar:
 "Ran into this limit recently, so increase it by an order of magnitude"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  printk: Increase maximum CONFIG_LOG_BUF_SHIFT from 21 to 25
2015-07-04 08:16:41 -07:00
Naveen N. Rao f6db834799 sched/stat: Simplify the sched_info accounting dependency
Both CONFIG_SCHEDSTATS=y and CONFIG_TASK_DELAY_ACCT=y track task
sched_info, which results in ugly #if clauses.

Simplify the code by introducing a synthethic CONFIG_SCHED_INFO
switch, selected by both.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: a.p.zijlstra@chello.nl
Cc: ricklind@us.ibm.com
Link: http://lkml.kernel.org/r/8d19eef800811a94b0f91bcbeb27430a884d7433.1435255405.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04 10:04:30 +02:00
Linus Torvalds 2d01eedf1d Merge branch 'akpm' (patches from Andrew)
Merge third patchbomb from Andrew Morton:

 - the rest of MM

 - scripts/gdb updates

 - ipc/ updates

 - lib/ updates

 - MAINTAINERS updates

 - various other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits)
  genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()
  genalloc: rename dev_get_gen_pool() to gen_pool_get()
  x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit
  MAINTAINERS: add zpool
  MAINTAINERS: BCACHE: Kent Overstreet has changed email address
  MAINTAINERS: move Jens Osterkamp to CREDITS
  MAINTAINERS: remove unused nbd.h pattern
  MAINTAINERS: update brcm gpio filename pattern
  MAINTAINERS: update brcm dts pattern
  MAINTAINERS: update sound soc intel patterns
  MAINTAINERS: remove website for paride
  MAINTAINERS: update Emulex ocrdma email addresses
  bcache: use kvfree() in various places
  libcxgbi: use kvfree() in cxgbi_free_big_mem()
  target: use kvfree() in session alloc and free
  IB/ehca: use kvfree() in ipz_queue_{cd}tor()
  drm/nouveau/gem: use kvfree() in u_free()
  drm: use kvfree() in drm_free_large()
  cxgb4: use kvfree() in t4_free_mem()
  cxgb3: use kvfree() in cxgb_free_mem()
  ...
2015-07-01 17:47:51 -07:00
Linus Torvalds 02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Ingo Molnar fb39f98d14 printk: Increase maximum CONFIG_LOG_BUF_SHIFT from 21 to 25
So I tried to some kernel debugging that produced a ton of kernel messages
on a big box, and wanted to save them all: but CONFIG_LOG_BUF_SHIFT maxes
out at 21 (2 MB).

Increase it to 25 (32 MB).

This does not affect any existing config or defaults.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-01 10:19:11 +02:00
Mel Gorman 0e1cc95b4c mm: meminit: finish initialisation of struct pages before basic setup
Waiman Long reported that 24TB machines hit OOM during basic setup when
struct page initialisation was deferred.  One approach is to initialise
memory on demand but it interferes with page allocator paths.  This patch
creates dedicated threads to initialise memory before basic setup.  It
then blocks on a rw_semaphore until completion as a wait_queue and counter
is overkill.  This may be slower to boot but it's simplier overall and
also gets rid of a section mangling which existed so kswapd could do the
initialisation.

[akpm@linux-foundation.org: include rwsem.h, use DECLARE_RWSEM, fix comment, remove unneeded cast]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Waiman Long <waiman.long@hp.com
Cc: Nathan Zimmer <nzimmer@sgi.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Scott Norton <scott.norton@hp.com>
Tested-by: Daniel J Blueman <daniel@numascale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:56 -07:00
Linus Torvalds bbe179f88d Merge branch 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:

 - threadgroup_lock got reorganized so that its users can pick the
   actual locking mechanism to use.  Its only user - cgroups - is
   updated to use a percpu_rwsem instead of per-process rwsem.

   This makes things a bit lighter on hot paths and allows cgroups to
   perform and fail multi-task (a process) migrations atomically.
   Multi-task migrations are used in several places including the
   unified hierarchy.

 - Delegation rule and documentation added to unified hierarchy.  This
   will likely be the last interface update from the cgroup core side
   for unified hierarchy before lifting the devel mask.

 - Some groundwork for the pids controller which is scheduled to be
   merged in the coming devel cycle.

* 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: add delegation section to unified hierarchy documentation
  cgroup: require write perm on common ancestor when moving processes on the default hierarchy
  cgroup: separate out cgroup_procs_write_permission() from __cgroup_procs_write()
  kernfs: make kernfs_get_inode() public
  MAINTAINERS: add a cgroup core co-maintainer
  cgroup: fix uninitialised iterator in for_each_subsys_which
  cgroup: replace explicit ss_mask checking with for_each_subsys_which
  cgroup: use bitmask to filter for_each_subsys
  cgroup: add seq_file forward declaration for struct cftype
  cgroup: simplify threadgroup locking
  sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem
  sched, cgroup: reorganize threadgroup locking
  cgroup: switch to unsigned long for bitmasks
  cgroup: reorganize include/linux/cgroup.h
  cgroup: separate out include/linux/cgroup-defs.h
  cgroup: fix some comment typos
2015-06-26 19:50:04 -07:00
Linus Torvalds 8d7804a2f0 Driver core patches for 4.2-rc1
Here is the driver core / firmware changes for 4.2-rc1.
 
 A number of small changes all over the place in the driver core, and in
 the firmware subsystem.  Nothing really major, full details in the
 shortlog.  Some of it is a bit of churn, given that the platform driver
 probing changes was found to not work well, so they were reverted.
 
 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 'driver-core-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the driver core / firmware changes for 4.2-rc1.

  A number of small changes all over the place in the driver core, and
  in the firmware subsystem.  Nothing really major, full details in the
  shortlog.  Some of it is a bit of churn, given that the platform
  driver probing changes was found to not work well, so they were
  reverted.

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

* tag 'driver-core-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits)
  Revert "base/platform: Only insert MEM and IO resources"
  Revert "base/platform: Continue on insert_resource() error"
  Revert "of/platform: Use platform_device interface"
  Revert "base/platform: Remove code duplication"
  firmware: add missing kfree for work on async call
  fs: sysfs: don't pass count == 0 to bin file readers
  base:dd - Fix for typo in comment to function driver_deferred_probe_trigger().
  base/platform: Remove code duplication
  of/platform: Use platform_device interface
  base/platform: Continue on insert_resource() error
  base/platform: Only insert MEM and IO resources
  firmware: use const for remaining firmware names
  firmware: fix possible use after free on name on asynchronous request
  firmware: check for file truncation on direct firmware loading
  firmware: fix __getname() missing failure check
  drivers: of/base: move of_init to driver_init
  drivers/base: cacheinfo: fix annoying typo when DT nodes are absent
  sysfs: disambiguate between "error code" and "failure" in comments
  driver-core: fix build for !CONFIG_MODULES
  driver-core: make __device_attach() static
  ...
2015-06-26 15:07:37 -07:00
Linus Torvalds 47a469421d Merge branch 'akpm' (patches from Andrew)
Merge second patchbomb from Andrew Morton:

 - most of the rest of MM

 - lots of misc things

 - procfs updates

 - printk feature work

 - updates to get_maintainer, MAINTAINERS, checkpatch

 - lib/ updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (96 commits)
  exit,stats: /* obey this comment */
  coredump: add __printf attribute to cn_*printf functions
  coredump: use from_kuid/kgid when formatting corename
  fs/reiserfs: remove unneeded cast
  NILFS2: support NFSv2 export
  fs/befs/btree.c: remove unneeded initializations
  fs/minix: remove unneeded cast
  init/do_mounts.c: add create_dev() failure log
  kasan: remove duplicate definition of the macro KASAN_FREE_PAGE
  fs/efs: femove unneeded cast
  checkpatch: emit "NOTE: <types>" message only once after multiple files
  checkpatch: emit an error when there's a diff in a changelog
  checkpatch: validate MODULE_LICENSE content
  checkpatch: add multi-line handling for PREFER_ETHER_ADDR_COPY
  checkpatch: suggest using eth_zero_addr() and eth_broadcast_addr()
  checkpatch: fix processing of MEMSET issues
  checkpatch: suggest using ether_addr_equal*()
  checkpatch: avoid NOT_UNIFIED_DIFF errors on cover-letter.patch files
  checkpatch: remove local from codespell path
  checkpatch: add --showfile to allow input via pipe to show filenames
  ...
2015-06-26 09:52:05 -07:00
Vishnu Pratap Singh c69e3c3a0c init/do_mounts.c: add create_dev() failure log
If create_dev() function fails to create the root mount device
(/dev/root), then it goes to panic as root device not found but there is
no printk in this case.  So I have added the log in case it fails to
create the root device.  It will help in debugging.

[akpm@linux-foundation.org: simplify printk(), use pr_emerg(), display errno]
Signed-off-by: Vishnu Pratap Singh <vishnu.ps@samsung.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Ehrenberg <dehrenberg@chromium.org>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25 17:00:42 -07:00
Iago López Galeiras 2e13ba54a2 fs, proc: introduce CONFIG_PROC_CHILDREN
Commit 818411616b ("fs, proc: introduce /proc/<pid>/task/<tid>/children
entry") introduced the children entry for checkpoint restore and the
file is only available on kernels configured with CONFIG_EXPERT and
CONFIG_CHECKPOINT_RESTORE.

This is available in most distributions (Fedora, Debian, Ubuntu, CoreOS)
because they usually enable CONFIG_EXPERT and CONFIG_CHECKPOINT_RESTORE.
But Arch does not enable CONFIG_EXPERT or CONFIG_CHECKPOINT_RESTORE.

However, the children proc file is useful outside of checkpoint restore.
I would like to use it in rkt.  The rkt process exec() another program
it does not control, and that other program will fork()+exec() a child
process.  I would like to find the pid of the child process from an
external tool without iterating in /proc over all processes to find
which one has a parent pid equal to rkt.

This commit introduces CONFIG_PROC_CHILDREN and makes
CONFIG_CHECKPOINT_RESTORE select it.  This allows enabling
/proc/<pid>/task/<tid>/children without needing to enable
CONFIG_CHECKPOINT_RESTORE and CONFIG_EXPERT.

Alban tested that /proc/<pid>/task/<tid>/children is present when the
kernel is configured with CONFIG_PROC_CHILDREN=y but without
CONFIG_CHECKPOINT_RESTORE

Signed-off-by: Iago López Galeiras <iago@endocode.com>
Tested-by: Alban Crequy <alban@endocode.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Djalal Harouni <djalal@endocode.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25 17:00:37 -07:00
Linus Torvalds e4bc13adfd Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block
Pull cgroup writeback support from Jens Axboe:
 "This is the big pull request for adding cgroup writeback support.

  This code has been in development for a long time, and it has been
  simmering in for-next for a good chunk of this cycle too.  This is one
  of those problems that has been talked about for at least half a
  decade, finally there's a solution and code to go with it.

  Also see last weeks writeup on LWN:

        http://lwn.net/Articles/648292/"

* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
  writeback, blkio: add documentation for cgroup writeback support
  vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
  writeback: do foreign inode detection iff cgroup writeback is enabled
  v9fs: fix error handling in v9fs_session_init()
  bdi: fix wrong error return value in cgwb_create()
  buffer: remove unusued 'ret' variable
  writeback: disassociate inodes from dying bdi_writebacks
  writeback: implement foreign cgroup inode bdi_writeback switching
  writeback: add lockdep annotation to inode_to_wb()
  writeback: use unlocked_inode_to_wb transaction in inode_congested()
  writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
  writeback: implement [locked_]inode_to_wb_and_lock_list()
  writeback: implement foreign cgroup inode detection
  writeback: make writeback_control track the inode being written back
  writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
  mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
  writeback: implement memcg writeback domain based throttling
  writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
  writeback: implement memcg wb_domain
  writeback: update wb_over_bg_thresh() to use wb_domain aware operations
  ...
2015-06-25 16:00:17 -07:00
Linus Torvalds 43c9fad942 Power management and ACPI material for v4.2-rc1
- ACPICA update to upstream revision 20150515 including basic
    support for ACPI 6 features: new ACPI tables introduced by
    ACPI 6 (STAO, XENV, WPBT, NFIT, IORT), changes related to the
    other tables (DTRM, FADT, LPIT, MADT), new predefined names
    (_BTH, _CR3, _DSD, _LPI, _MTL, _PRR, _RDI, _RST, _TFP, _TSN),
    fixes and cleanups (Bob Moore, Lv Zheng).
 
  - ACPI device power management core code update to follow ACPI 6
    which reflects the ACPI device power management implementation
    in Windows (Rafael J Wysocki).
 
  - Rework of the backlight interface selection logic to reduce the
    number of kernel command line options and improve the handling
    of DMI quirks that may be involved in that and to make the
    code generally more straightforward (Hans de Goede).
 
  - Fixes for the ACPI Embedded Controller (EC) driver related to
    the handling of EC transactions (Lv Zheng).
 
  - Fix for a regression related to the ACPI resources management
    and resulting from a recent change of ACPI initialization code
    ordering (Rafael J Wysocki).
 
  - Fix for a system initialization regression related to ACPI
    introduced during the 3.14 cycle and caused by running the
    code that switches the platform over to the ACPI mode too
    early in the initialization sequence (Rafael J Wysocki).
 
  - Support for the ACPI _CCA device configuration object related
    to DMA cache coherence (Suravee Suthikulpanit).
 
  - ACPI/APEI fixes and cleanups (Jiri Kosina, Borislav Petkov).
 
  - ACPI battery driver cleanups (Luis Henriques, Mathias Krause).
 
  - ACPI processor driver cleanups (Hanjun Guo).
 
  - Cleanups and documentation update related to the ACPI device
    properties interface based on _DSD (Rafael J Wysocki).
 
  - ACPI device power management fixes (Rafael J Wysocki).
 
  - Assorted cleanups related to ACPI (Dominik Brodowski. Fabian
    Frederick, Lorenzo Pieralisi, Mathias Krause, Rafael J Wysocki).
 
  - Fix for a long-standing issue causing General Protection Faults
    to be generated occasionally on return to user space after resume
    from ACPI-based suspend-to-RAM on 32-bit x86 (Ingo Molnar).
 
  - Fix to make the suspend core code return -EBUSY consistently in
    all cases when system suspend is aborted due to wakeup detection
    (Ruchi Kandoi).
 
  - Support for automated device wakeup IRQ handling allowing drivers
    to make their PM support more starightforward (Tony Lindgren).
 
  - New tracepoints for suspend-to-idle tracing and rework of the
    prepare/complete callbacks tracing in the PM core (Todd E Brandt,
    Rafael J Wysocki).
 
  - Wakeup sources framework enhancements (Jin Qian).
 
  - New macro for noirq system PM callbacks (Grygorii Strashko).
 
  - Assorted cleanups related to system suspend (Rafael J Wysocki).
 
  - cpuidle core cleanups to make the code more efficient (Rafael J
    Wysocki).
 
  - powernv/pseries cpuidle driver update (Shilpasri G Bhat).
 
  - cpufreq core fixes related to CPU online/offline that should
    reduce the overhead of these operations quite a bit, unless the
    CPU in question is physically going away (Viresh Kumar, Saravana
    Kannan).
 
  - Serialization of cpufreq governor callbacks to avoid race
    conditions in some cases (Viresh Kumar).
 
  - intel_pstate driver fixes and cleanups (Doug Smythies, Prarit
    Bhargava, Joe Konno).
 
  - cpufreq driver (arm_big_little, cpufreq-dt, qoriq) updates (Sudeep
    Holla, Felipe Balbi, Tang Yuantian).
 
  - Assorted cleanups in cpufreq drivers and core (Shailendra Verma,
    Fabian Frederick, Wang Long).
 
  - New Device Tree bindings for representing Operating Performance
    Points (Viresh Kumar).
 
  - Updates for the common clock operations support code in the PM
    core (Rajendra Nayak, Geert Uytterhoeven).
 
  - PM domains core code update (Geert Uytterhoeven).
 
  - Intel Knights Landing support for the RAPL (Running Average Power
    Limit) power capping driver (Dasaratharaman Chandramouli).
 
  - Fixes related to the floor frequency setting on Atom SoCs in the
    RAPL power capping driver (Ajay Thomas).
 
  - Runtime PM framework documentation update (Ben Dooks).
 
  - cpupower tool fix (Herton R Krzesinski).
 
 /
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Merge tag 'pm+acpi-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "The rework of backlight interface selection API from Hans de Goede
  stands out from the number of commits and the number of affected
  places perspective.  The cpufreq core fixes from Viresh Kumar are
  quite significant too as far as the number of commits goes and because
  they should reduce CPU online/offline overhead quite a bit in the
  majority of cases.

  From the new featues point of view, the ACPICA update (to upstream
  revision 20150515) adding support for new ACPI 6 material to ACPICA is
  the one that matters the most as some new significant features will be
  based on it going forward.  Also included is an update of the ACPI
  device power management core to follow ACPI 6 (which in turn reflects
  the Windows' device PM implementation), a PM core extension to support
  wakeup interrupts in a more generic way and support for the ACPI _CCA
  device configuration object.

  The rest is mostly fixes and cleanups all over and some documentation
  updates, including new DT bindings for Operating Performance Points.

  There is one fix for a regression introduced in the 4.1 cycle, but it
  adds quite a number of lines of code, it wasn't really ready before
  Thursday and you were on vacation, so I refrained from pushing it on
  the last minute for 4.1.

  Specifics:

   - ACPICA update to upstream revision 20150515 including basic support
     for ACPI 6 features: new ACPI tables introduced by ACPI 6 (STAO,
     XENV, WPBT, NFIT, IORT), changes related to the other tables (DTRM,
     FADT, LPIT, MADT), new predefined names (_BTH, _CR3, _DSD, _LPI,
     _MTL, _PRR, _RDI, _RST, _TFP, _TSN), fixes and cleanups (Bob Moore,
     Lv Zheng).

   - ACPI device power management core code update to follow ACPI 6
     which reflects the ACPI device power management implementation in
     Windows (Rafael J Wysocki).

   - rework of the backlight interface selection logic to reduce the
     number of kernel command line options and improve the handling of
     DMI quirks that may be involved in that and to make the code
     generally more straightforward (Hans de Goede).

   - fixes for the ACPI Embedded Controller (EC) driver related to the
     handling of EC transactions (Lv Zheng).

   - fix for a regression related to the ACPI resources management and
     resulting from a recent change of ACPI initialization code ordering
     (Rafael J Wysocki).

   - fix for a system initialization regression related to ACPI
     introduced during the 3.14 cycle and caused by running the code
     that switches the platform over to the ACPI mode too early in the
     initialization sequence (Rafael J Wysocki).

   - support for the ACPI _CCA device configuration object related to
     DMA cache coherence (Suravee Suthikulpanit).

   - ACPI/APEI fixes and cleanups (Jiri Kosina, Borislav Petkov).

   - ACPI battery driver cleanups (Luis Henriques, Mathias Krause).

   - ACPI processor driver cleanups (Hanjun Guo).

   - cleanups and documentation update related to the ACPI device
     properties interface based on _DSD (Rafael J Wysocki).

   - ACPI device power management fixes (Rafael J Wysocki).

   - assorted cleanups related to ACPI (Dominik Brodowski, Fabian
     Frederick, Lorenzo Pieralisi, Mathias Krause, Rafael J Wysocki).

   - fix for a long-standing issue causing General Protection Faults to
     be generated occasionally on return to user space after resume from
     ACPI-based suspend-to-RAM on 32-bit x86 (Ingo Molnar).

   - fix to make the suspend core code return -EBUSY consistently in all
     cases when system suspend is aborted due to wakeup detection (Ruchi
     Kandoi).

   - support for automated device wakeup IRQ handling allowing drivers
     to make their PM support more starightforward (Tony Lindgren).

   - new tracepoints for suspend-to-idle tracing and rework of the
     prepare/complete callbacks tracing in the PM core (Todd E Brandt,
     Rafael J Wysocki).

   - wakeup sources framework enhancements (Jin Qian).

   - new macro for noirq system PM callbacks (Grygorii Strashko).

   - assorted cleanups related to system suspend (Rafael J Wysocki).

   - cpuidle core cleanups to make the code more efficient (Rafael J
     Wysocki).

   - powernv/pseries cpuidle driver update (Shilpasri G Bhat).

   - cpufreq core fixes related to CPU online/offline that should reduce
     the overhead of these operations quite a bit, unless the CPU in
     question is physically going away (Viresh Kumar, Saravana Kannan).

   - serialization of cpufreq governor callbacks to avoid race
     conditions in some cases (Viresh Kumar).

   - intel_pstate driver fixes and cleanups (Doug Smythies, Prarit
     Bhargava, Joe Konno).

   - cpufreq driver (arm_big_little, cpufreq-dt, qoriq) updates (Sudeep
     Holla, Felipe Balbi, Tang Yuantian).

   - assorted cleanups in cpufreq drivers and core (Shailendra Verma,
     Fabian Frederick, Wang Long).

   - new Device Tree bindings for representing Operating Performance
     Points (Viresh Kumar).

   - updates for the common clock operations support code in the PM core
     (Rajendra Nayak, Geert Uytterhoeven).

   - PM domains core code update (Geert Uytterhoeven).

   - Intel Knights Landing support for the RAPL (Running Average Power
     Limit) power capping driver (Dasaratharaman Chandramouli).

   - fixes related to the floor frequency setting on Atom SoCs in the
     RAPL power capping driver (Ajay Thomas).

   - runtime PM framework documentation update (Ben Dooks).

   - cpupower tool fix (Herton R Krzesinski)"

* tag 'pm+acpi-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (194 commits)
  cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state
  x86: Load __USER_DS into DS/ES after resume
  PM / OPP: Add binding for 'opp-suspend'
  PM / OPP: Allow multiple OPP tables to be passed via DT
  PM / OPP: Add new bindings to address shortcomings of existing bindings
  ACPI: Constify ACPI device IDs in documentation
  ACPI / enumeration: Document the rules regarding the PRP0001 device ID
  ACPI / video: Make acpi_video_unregister_backlight() private
  acpi-video-detect: Remove old API
  toshiba-acpi: Port to new backlight interface selection API
  thinkpad-acpi: Port to new backlight interface selection API
  sony-laptop: Port to new backlight interface selection API
  samsung-laptop: Port to new backlight interface selection API
  msi-wmi: Port to new backlight interface selection API
  msi-laptop: Port to new backlight interface selection API
  intel-oaktrail: Port to new backlight interface selection API
  ideapad-laptop: Port to new backlight interface selection API
  fujitsu-laptop: Port to new backlight interface selection API
  eeepc-laptop: Port to new backlight interface selection API
  dell-wmi: Port to new backlight interface selection API
  ...
2015-06-23 14:18:07 -07:00
Rusty Russell b6c09b512d modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
Andreas turned this option on, only to find out Debian (and Ubuntu!)
don't enable support in their kmod builds.

Shorten the text, and suggest N at the bottom (at least for now).

Reported-by: Andreas Mohr <andim2@users.sf.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-23 15:27:36 +09:30
Linus Torvalds c58267e9fa Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Kernel side changes mostly consist of work on x86 PMU drivers:

   - x86 Intel PT (hardware CPU tracer) improvements (Alexander
     Shishkin)

   - x86 Intel CQM (cache quality monitoring) improvements (Thomas
     Gleixner)

   - x86 Intel PEBSv3 support (Peter Zijlstra)

   - x86 Intel PEBS interrupt batching support for lower overhead
     sampling (Zheng Yan, Kan Liang)

   - x86 PMU scheduler fixes and improvements (Peter Zijlstra)

  There's too many tooling improvements to list them all - here are a
  few select highlights:

  'perf bench':

      - Introduce new 'perf bench futex' benchmark: 'wake-parallel', to
        measure parallel waker threads generating contention for kernel
        locks (hb->lock). (Davidlohr Bueso)

  'perf top', 'perf report':

      - Allow disabling/enabling events dynamicaly in 'perf top':
        a 'perf top' session can instantly become a 'perf report'
        one, i.e. going from dynamic analysis to a static one,
        returning to a dynamic one is possible, to toogle the
        modes, just press 'f' to 'freeze/unfreeze' the sampling. (Arnaldo Carvalho de Melo)

      - Make Ctrl-C stop processing on TUI, allowing interrupting the load of big
        perf.data files (Namhyung Kim)

  'perf probe': (Masami Hiramatsu)

      - Support glob wildcards for function name
      - Support $params special probe argument: Collect all function arguments
      - Make --line checks validate C-style function name.
      - Add --no-inlines option to avoid searching inline functions
      - Greatly speed up 'perf probe --list' by caching debuginfo.
      - Improve --filter support for 'perf probe', allowing using its arguments
        on other commands, as --add, --del, etc.

  'perf sched':

      - Add option in 'perf sched' to merge like comms to lat output (Josef Bacik)

  Plus tons of infrastructure work - in particular preparation for
  upcoming threaded perf report support, but also lots of other work -
  and fixes and other improvements.  See (much) more details in the
  shortlog and in the git log"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (305 commits)
  perf tools: Configurable per thread proc map processing time out
  perf tools: Add time out to force stop proc map processing
  perf report: Fix sort__sym_cmp to also compare end of symbol
  perf hists browser: React to unassigned hotkey pressing
  perf top: Tell the user how to unfreeze events after pressing 'f'
  perf hists browser: Honour the help line provided by builtin-{top,report}.c
  perf hists browser: Do not exit when 'f' is pressed in 'report' mode
  perf top: Replace CTRL+z with 'f' as hotkey for enable/disable events
  perf annotate: Rename source_line_percent to source_line_samples
  perf annotate: Display total number of samples with --show-total-period
  perf tools: Ensure thread-stack is flushed
  perf top: Allow disabling/enabling events dynamicly
  perf evlist: Add toggle_enable() method
  perf trace: Fix race condition at the end of started workloads
  perf probe: Speed up perf probe --list by caching debuginfo
  perf probe: Show usage even if the last event is skipped
  perf tools: Move libtraceevent dynamic list to separated LDFLAGS variable
  perf tools: Fix a problem when opening old perf.data with different byte order
  perf tools: Ignore .config-detected in .gitignore
  perf probe: Fix to return error if no probe is added
  ...
2015-06-22 15:19:21 -07:00
Rafael J. Wysocki b064a8fa77 ACPI / init: Switch over platform to the ACPI mode later
Commit 73f7d1ca32 "ACPI / init: Run acpi_early_init() before
timekeeping_init()" moved the ACPI subsystem initialization,
including the ACPI mode enabling, to an earlier point in the
initialization sequence, to allow the timekeeping subsystem
use ACPI early.  Unfortunately, that resulted in boot regressions
on some systems and the early ACPI initialization was moved toward
its original position in the kernel initialization code by commit
c4e1acbb35 "ACPI / init: Invoke early ACPI initialization later".

However, that turns out to be insufficient, as boot is still broken
on the Tyan S8812 mainboard.

To fix that issue, split the ACPI early initialization code into
two pieces so the majority of it still located in acpi_early_init()
and the part switching over the platform into the ACPI mode goes into
a new function, acpi_subsystem_init(), executed at the original early
ACPI initialization spot.

That fixes the Tyan S8812 boot problem, but still allows ACPI
tables to be loaded earlier which is useful to the EFI code in
efi_enter_virtual_mode().

Link: https://bugzilla.kernel.org/show_bug.cgi?id=97141
Fixes: 73f7d1ca32 "ACPI / init: Run acpi_early_init() before timekeeping_init()"
Reported-and-tested-by: Marius Tolzmann <tolzmann@molgen.mpg.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Lee, Chun-Yi <jlee@suse.com>
2015-06-10 23:51:27 +02:00
Tejun Heo 89e9b9e07a writeback: add {CONFIG|BDI_CAP|FS}_CGROUP_WRITEBACK
cgroup writeback requires support from both bdi and filesystem sides.
Add BDI_CAP_CGROUP_WRITEBACK and FS_CGROUP_WRITEBACK to indicate
support and enable BDI_CAP_CGROUP_WRITEBACK on block based bdi's by
default.  Also, define CONFIG_CGROUP_WRITEBACK which is enabled if
both MEMCG and BLK_CGROUP are enabled.

inode_cgwb_enabled() which determines whether a given inode's both bdi
and fs support cgroup writeback is added.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:35 -06:00
Peter Zijlstra 6c9692e2d6 module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
Andrew worried about the overhead on small systems; only use the fancy
code when either perf or tracing is enabled.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Requested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28 11:32:07 +09:30
Pranith Kumar e72aeafc66 rcu: Remove prompt for RCU implementation
The RCU implementation is chosen based on PREEMPT and SMP config options
and is not really a user-selectable choice.  This commit removes the
menu entry, given that there is not much point in calling something a
choice when there is in fact no choice..  The TINY_RCU, TREE_RCU, and
PREEMPT_RCU Kconfig options continue to be selected based solely on the
values of the PREEMPT and SMP options.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-05-27 12:59:06 -07:00
Paul E. McKenney 26730f55c2 rcu: Make RCU able to tolerate undefined CONFIG_RCU_KTHREAD_PRIO
This commit updates the initialization of the kthread_prio boot parameter
so that RCU will build even when CONFIG_RCU_KTHREAD_PRIO is undefined.
The kthread_prio boot parameter is set to CONFIG_RCU_KTHREAD_PRIO if
that is defined, otherwise to 1 if CONFIG_RCU_BOOST is defined and
to zero otherwise.  This commit then makes CONFIG_RCU_KTHREAD_PRIO
depend on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about
CONFIG_RCU_KTHREAD_PRIO unless they want to be.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:06 -07:00
Paul E. McKenney 47d631af58 rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUT_LEAF
This commit introduces an RCU_FANOUT_LEAF C-preprocessor macro so
that RCU will build even when CONFIG_RCU_FANOUT_LEAF is undefined.
The RCU_FANOUT_LEAF macro is set to the value of CONFIG_RCU_FANOUT_LEAF
when defined, otherwise it is set to 32 for 32-bit systems and 64 for
64-bit systems.  This commit then makes CONFIG_RCU_FANOUT_LEAF depend
on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about
CONFIG_RCU_FANOUT_LEAF unless they want to be.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:05 -07:00
Paul E. McKenney 05c5df31af rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUT
This commit introduces an RCU_FANOUT C-preprocessor macro so that RCU will
build even when CONFIG_RCU_FANOUT is undefined.  The RCU_FANOUT macro is
set to the value of CONFIG_RCU_FANOUT when defined, otherwise it is set
to 32 for 32-bit systems and 64 for 64-bit systems.  This commit then
makes CONFIG_RCU_FANOUT depend on CONFIG_RCU_EXPERT, so that Kconfig
users won't be asked about CONFIG_RCU_FANOUT unless they want to be.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:05 -07:00
Paul E. McKenney 8739c5cb0f rcu: Break dependency of RCU_FANOUT_LEAF on RCU_FANOUT
RCU_FANOUT_LEAF's range and default values depend on the value of
RCU_FANOUT, which at the time seemed like a cute way to save two lines
of Kconfig code.  However, adding a dependency from both of these
Kconfig parameters on RCU_EXPERT requires that RCU_FANOUT_LEAF operate
correctly even if RCU_FANOUT is undefined.  This commit therefore
allows RCU_FANOUT_LEAF to take on the full range of permitted values,
even in cases where RCU_FANOUT is undefined.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Eliminate redundant "default" as suggested by Pranith Kumar. ]
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:05 -07:00
Paul E. McKenney 78cae10b3a rcu: Create RCU_EXPERT Kconfig and hide booleans behind it
This commit creates an RCU_EXPERT Kconfig and hides the independent
boolean RCU-related user-visible Kconfig parameters behind it, namely
RCU_FAST_NO_HZ and RCU_BOOST.  This prevents Kconfig from asking about
these parameters unless the user really wants to be asked.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:04 -07:00
Paul E. McKenney 7fa270010e rcu: Convert CONFIG_RCU_FANOUT_EXACT to boot parameter
The CONFIG_RCU_FANOUT_EXACT Kconfig parameter is used primarily (and
perhaps only) by rcutorture to verify that RCU works correctly in specific
rcu_node combining-tree configurations.  It therefore does not make
much sense have this as a question to people attempting to configure
their kernels.  So this commit creates an rcutree.rcu_fanout_exact=
boot parameter that rcutorture can use, and eliminates the original
CONFIG_RCU_FANOUT_EXACT Kconfig parameter.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:04 -07:00
Paul E. McKenney 7db21edfec rcu: Directly drive RCU_USER_QS from Kconfig
Currently, Kconfig will ask the user whether RCU_USER_QS should be set.
This is silly because Kconfig already has all the information that it
needs to set this parameter.  This commit therefore directly drives
the value of RCU_USER_QS via NO_HZ_FULL's "select" statement.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
2015-05-27 12:59:03 -07:00
Paul E. McKenney 82d0f4c089 rcu: Directly drive TASKS_RCU from Kconfig
Currently, Kconfig will ask the user whether TASKS_RCU should be set.
This is silly because Kconfig already has all the information that it
needs to set this parameter.  This commit therefore directly drives
the value of TASKS_RCU via "select" statements.  Which means that
as subsystems require TASKS_RCU, those subsystems will need to add
"select" statements of their own.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2015-05-27 12:59:03 -07:00
Ingo Molnar 8d12ded3dd Merge branch 'perf/urgent' into perf/core, before applying dependent patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-27 09:17:21 +02:00
Tejun Heo d59cfc09c3 sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem
The cgroup side of threadgroup locking uses signal_struct->group_rwsem
to synchronize against threadgroup changes.  This per-process rwsem
adds small overhead to thread creation, exit and exec paths, forces
cgroup code paths to do lock-verify-unlock-retry dance in a couple
places and makes it impossible to atomically perform operations across
multiple processes.

This patch replaces signal_struct->group_rwsem with a global
percpu_rwsem cgroup_threadgroup_rwsem which is cheaper on the reader
side and contained in cgroups proper.  This patch converts one-to-one.

This does make writer side heavier and lower the granularity; however,
cgroup process migration is a fairly cold path, we do want to optimize
thread operations over it and cgroup migration operations don't take
enough time for the lower granularity to matter.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2015-05-26 20:35:00 -04:00
Luis R. Rodriguez ecc8617053 module: add extra argument for parse_params() callback
This adds an extra argument onto parse_params() to be used
as a way to make the unused callback a bit more useful and
generic by allowing the caller to pass on a data structure
of its choice. An example use case is to allow us to easily
make module parameters for every module which we will do
next.

@ parse @
identifier name, args, params, num, level_min, level_max;
identifier unknown, param, val, doing;
type s16;
@@
 extern char *parse_args(const char *name,
 			 char *args,
 			 const struct kernel_param *params,
 			 unsigned num,
 			 s16 level_min,
 			 s16 level_max,
+			 void *arg,
 			 int (*unknown)(char *param, char *val,
					const char *doing
+					, void *arg
					));

@ parse_mod @
identifier name, args, params, num, level_min, level_max;
identifier unknown, param, val, doing;
type s16;
@@
 char *parse_args(const char *name,
 			 char *args,
 			 const struct kernel_param *params,
 			 unsigned num,
 			 s16 level_min,
 			 s16 level_max,
+			 void *arg,
 			 int (*unknown)(char *param, char *val,
					const char *doing
+					, void *arg
					))
{
	...
}

@ parse_args_found @
expression R, E1, E2, E3, E4, E5, E6;
identifier func;
@@

(
	R =
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   func);
|
	R =
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   &func);
|
	R =
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   NULL);
|
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   func);
|
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   &func);
|
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   NULL);
)

@ parse_args_unused depends on parse_args_found @
identifier parse_args_found.func;
@@

int func(char *param, char *val, const char *unused
+		 , void *arg
		 )
{
	...
}

@ mod_unused depends on parse_args_found @
identifier parse_args_found.func;
expression A1, A2, A3;
@@

-	func(A1, A2, A3);
+	func(A1, A2, A3, NULL);

Generated-by: Coccinelle SmPL
Cc: cocci@systeme.lip6.fr
Cc: Tejun Heo <tj@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Felipe Contreras <felipe.contreras@gmail.com>
Cc: Ewan Milne <emilne@redhat.com>
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-20 00:25:24 -07:00
Michael Ellerman cb30711374 perf_event: Don't allow vmalloc() backed perf on powerpc
On powerpc the perf event interrupt is not masked when interrupts are
disabled, allowing it to function as an NMI.

This causes problems if perf is using vmalloc. If we take a page fault
on the vmalloc region the fault handler will fail the page fault because
it detects we are coming in from an NMI (see do_hash_page()).

We don't actually need or want vmalloc backed perf so just disable it on
powerpc.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <linuxppc-dev@ozlabs.org>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@ghostprotocols.net
Cc: sukadev@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1430720799-18426-1-git-send-email-mpe@ellerman.id.au
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:26:01 +02:00
Chen Yu cb31ef485d init: fix regression by supporting devices with major:minor:offset format
Commit 283e7ad02 ("init: stricter checking of major:minor root=
values") was so strict that it exposed the fact that a previously
unknown device format was being used.

Distributions like Ubuntu uses klibc (rather than uswsusp) to resume
system from hibernation.  klibc expressed the swap partition/file in
the form of major:minor:offset.  For example, 8:3:0 represents a swap
partition in klibc, and klibc's resume process in initrd will finally
echo 8:3:0 to /sys/power/resume for manually resuming.  However, due
to commit 283e7ad02's stricter checking, 8:3:0 will be treated as an
invalid device format, and manual resuming from hibernation will fail.

Fix this by adding support for devices with major:minor:offset format
when resuming from hibernation.

Reported-by: Prigent, Christophe <christophe.prigent@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-05-05 12:31:37 -04:00
Linus Torvalds d6a24d0640 The documentation tree update for 4.1. Numerous fixes, the overdue removal
of the i2o docs, some new Chinese translations, and, hopefully, the README
 fix that will end the flow of identical patches to that file.
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Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6

Pull documentation updates from Jonathan Corbet:
 "Numerous fixes, the overdue removal of the i2o docs, some new Chinese
  translations, and, hopefully, the README fix that will end the flow of
  identical patches to that file"

* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (34 commits)
  Documentation/memcg: update memcg/kmem status
  Documentation: blackfin: Makefile: Typo building issue
  Documentation/vm/pagemap.txt: correct location of page-types tool
  Documentation/memory-barriers.txt: typo fix
  doc: Add guest_nice column to example output of `cat /proc/stat'
  Documentation/kernel-parameters: Move "eagerfpu" to its right place
  Documentation: gpio: Update ACPI part of the document to mention _DSD
  docs/completion.txt: Various tweaks and corrections
  doc: completion: context, scope and language fixes
  Documentation:Update Documentation/zh_CN/arm64/memory.txt
  Documentation:Update Documentation/zh_CN/arm64/booting.txt
  Documentation: Chinese translation of arm64/legacy_instructions.txt
  DocBook media: fix broken EIA hyperlink
  Documentation: tweak the maintainers entry
  README: Change gzip/bzip2 to xz compression format
  README: Update version number reference
  doc:pci: Fix typo in Documentation/PCI
  Documentation: drm: Use '->' when describing access through pointers.
  Documentation: Remove mentioning of block barriers
  Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB
  ...
2015-04-18 11:10:49 -04:00
Linus Torvalds afad97eee4 - Most extensive changes this cycle are the DM core improvements to add
full blk-mq support to request-based DM.
   - disabled by default but user can opt-in with CONFIG_DM_MQ_DEFAULT
   - depends on some blk-mq changes from Jens' for-4.1/core branch so
     that explains why this pull is built on linux-block.git
 
 - Update DM to use name_to_dev_t() rather than open-coding a less
   capable device parser.
   - includes a couple small improvements to name_to_dev_t() that offer
     stricter constraints that DM's code provided.
 
 - Improvements to the dm-cache "mq" cache replacement policy.
 
 - A DM crypt crypt_ctr() error path fix and an async crypto deadlock fix.
 
 - A small efficiency improvement for DM crypt decryption by leveraging
   immutable biovecs.
 
 - Add error handling modes for corrupted blocks to DM verity.
 
 - A new "log-writes" DM target from Josef Bacik that is meant for
   file system developers to test file system integrity at particular
   points in the life of a file system.
 
 - A few DM log userspace cleanups and fixes.
 
 - A few Documentation fixes (for thin, cache, crypt and switch).
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Merge tag 'dm-4.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - the most extensive changes this cycle are the DM core improvements to
   add full blk-mq support to request-based DM.

    - disabled by default but user can opt-in with CONFIG_DM_MQ_DEFAULT
    - depends on some blk-mq changes from Jens' for-4.1/core branch so
      that explains why this pull is built on linux-block.git

 - update DM to use name_to_dev_t() rather than open-coding a less
   capable device parser.

    - includes a couple small improvements to name_to_dev_t() that offer
      stricter constraints that DM's code provided.

 - improvements to the dm-cache "mq" cache replacement policy.

 - a DM crypt crypt_ctr() error path fix and an async crypto deadlock
   fix

 - a small efficiency improvement for DM crypt decryption by leveraging
   immutable biovecs

 - add error handling modes for corrupted blocks to DM verity

 - a new "log-writes" DM target from Josef Bacik that is meant for file
   system developers to test file system integrity at particular points
   in the life of a file system

 - a few DM log userspace cleanups and fixes

 - a few Documentation fixes (for thin, cache, crypt and switch)

* tag 'dm-4.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (34 commits)
  dm crypt: fix missing error code return from crypt_ctr error path
  dm crypt: fix deadlock when async crypto algorithm returns -EBUSY
  dm crypt: leverage immutable biovecs when decrypting on read
  dm crypt: update URLs to new cryptsetup project page
  dm: add log writes target
  dm table: use bool function return values of true/false not 1/0
  dm verity: add error handling modes for corrupted blocks
  dm thin: remove stale 'trim' message documentation
  dm delay: use msecs_to_jiffies for time conversion
  dm log userspace base: fix compile warning
  dm log userspace transfer: match wait_for_completion_timeout return type
  dm table: fall back to getting device using name_to_dev_t()
  init: stricter checking of major:minor root= values
  init: export name_to_dev_t and mark name argument as const
  dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr
  dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq
  dm: add full blk-mq support to request-based DM
  dm: impose configurable deadline for dm_request_fn's merge heuristic
  dm sysfs: introduce ability to add writable attributes
  dm: don't start current request if it would've merged with the previous
  ...
2015-04-18 08:14:18 -04:00
Heinrich Schuchardt ff691f6e03 kernel/fork.c: new function for max_threads
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the
THREAD_SIZE.

E.g.  architecture hexagon may have page size 1M and thread size 4096.
This would lead to a division by zero in the calculation of max_threads.

With this patch the buggy code is moved to a separate function
set_max_threads.  The error is not fixed.

After fixing the problem in a separate patch the new function can be
reused to adjust max_threads after adding or removing memory.

Argument mempages of function fork_init() is removed as totalram_pages is
an exported symbol.

The creation of separate patches for refactoring to a new function and for
fixing the logic was suggested by Ingo Molnar.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:06 -04:00
Iulia Manda 2813893f8b kernel: conditionally support non-root users, groups and capabilities
There are a lot of embedded systems that run most or all of their
functionality in init, running as root:root.  For these systems,
supporting multiple users is not necessary.

This patch adds a new symbol, CONFIG_MULTIUSER, that makes support for
non-root users, non-root groups, and capabilities optional.  It is enabled
under CONFIG_EXPERT menu.

When this symbol is not defined, UID and GID are zero in any possible case
and processes always have all capabilities.

The following syscalls are compiled out: setuid, setregid, setgid,
setreuid, setresuid, getresuid, setresgid, getresgid, setgroups,
getgroups, setfsuid, setfsgid, capget, capset.

Also, groups.c is compiled out completely.

In kernel/capability.c, capable function was moved in order to avoid
adding two ifdef blocks.

This change saves about 25 KB on a defconfig build.  The most minimal
kernels have total text sizes in the high hundreds of kB rather than
low MB.  (The 25k goes down a bit with allnoconfig, but not that much.

The kernel was booted in Qemu.  All the common functionalities work.
Adding users/groups is not possible, failing with -ENOSYS.

Bloat-o-meter output:
add/remove: 7/87 grow/shrink: 19/397 up/down: 1675/-26325 (-24650)

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Iulia Manda <iulia.manda21@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:22 -07:00
Dan Ehrenberg 283e7ad024 init: stricter checking of major:minor root= values
In the kernel command-line, previously, root=1:2jakshflaksjdhfa would
be accepted and interpreted just like root=1:2. This patch adds
stricter checking so that additional characters after major:minor are
rejected by root=.

The goal of this change is to help in unifying DM's interpretation of
its block device argument by using existing kernel code (name_to_dev_t).
But DM rejects malformed major:minor pairs, it seems reasonable for
root= to reject them as well.

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-15 12:10:19 -04:00
Dan Ehrenberg e6e20a7a5f init: export name_to_dev_t and mark name argument as const
DM will switch its device lookup code to using name_to_dev_t() so it
must be exported.  Also, the @name argument should be marked const.

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-15 12:10:18 -04:00
Linus Torvalds 1dcf58d6e6 Merge branch 'akpm' (patches from Andrew)
Merge first patchbomb from Andrew Morton:

 - arch/sh updates

 - ocfs2 updates

 - kernel/watchdog feature

 - about half of mm/

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits)
  Documentation: update arch list in the 'memtest' entry
  Kconfig: memtest: update number of test patterns up to 17
  arm: add support for memtest
  arm64: add support for memtest
  memtest: use phys_addr_t for physical addresses
  mm: move memtest under mm
  mm, hugetlb: abort __get_user_pages if current has been oom killed
  mm, mempool: do not allow atomic resizing
  memcg: print cgroup information when system panics due to panic_on_oom
  mm: numa: remove migrate_ratelimited
  mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE
  mm: split ET_DYN ASLR from mmap ASLR
  s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE
  mm: expose arch_mmap_rnd when available
  s390: standardize mmap_rnd() usage
  powerpc: standardize mmap_rnd() usage
  mips: extract logic for mmap_rnd()
  arm64: standardize mmap_rnd() usage
  x86: standardize mmap_rnd() usage
  arm: factor out mmap ASLR into mmap_rnd
  ...
2015-04-14 16:49:17 -07:00
Toshi Kani 0ddab1d2ed lib/ioremap.c: add huge I/O map capability interfaces
Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when
I/O mappings with pud/pmd are enabled on the kernel.

ioremap_huge_init() calls arch_ioremap_pud_supported() and
arch_ioremap_pmd_supported() to initialize the capabilities at boot-time.

A new kernel option "nohugeiomap" is also added, so that user can disable
the huge I/O map capabilities when necessary.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:04 -07:00
Linus Torvalds 6c8a53c9e6 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf changes from Ingo Molnar:
 "Core kernel changes:

   - One of the more interesting features in this cycle is the ability
     to attach eBPF programs (user-defined, sandboxed bytecode executed
     by the kernel) to kprobes.

     This allows user-defined instrumentation on a live kernel image
     that can never crash, hang or interfere with the kernel negatively.
     (Right now it's limited to root-only, but in the future we might
     allow unprivileged use as well.)

     (Alexei Starovoitov)

   - Another non-trivial feature is per event clockid support: this
     allows, amongst other things, the selection of different clock
     sources for event timestamps traced via perf.

     This feature is sought by people who'd like to merge perf generated
     events with external events that were measured with different
     clocks:

       - cluster wide profiling

       - for system wide tracing with user-space events,

       - JIT profiling events

     etc.  Matching perf tooling support is added as well, available via
     the -k, --clockid <clockid> parameter to perf record et al.

     (Peter Zijlstra)

  Hardware enablement kernel changes:

   - x86 Intel Processor Trace (PT) support: which is a hardware tracer
     on steroids, available on Broadwell CPUs.

     The hardware trace stream is directly output into the user-space
     ring-buffer, using the 'AUX' data format extension that was added
     to the perf core to support hardware constraints such as the
     necessity to have the tracing buffer physically contiguous.

     This patch-set was developed for two years and this is the result.
     A simple way to make use of this is to use BTS tracing, the PT
     driver emulates BTS output - available via the 'intel_bts' PMU.
     More explicit PT specific tooling support is in the works as well -
     will probably be ready by 4.2.

     (Alexander Shishkin, Peter Zijlstra)

   - x86 Intel Cache QoS Monitoring (CQM) support: this is a hardware
     feature of Intel Xeon CPUs that allows the measurement and
     allocation/partitioning of caches to individual workloads.

     These kernel changes expose the measurement side as a new PMU
     driver, which exposes various QoS related PMU events.  (The
     partitioning change is work in progress and is planned to be merged
     as a cgroup extension.)

     (Matt Fleming, Peter Zijlstra; CPU feature detection by Peter P
     Waskiewicz Jr)

   - x86 Intel Haswell LBR call stack support: this is a new Haswell
     feature that allows the hardware recording of call chains, plus
     tooling support.  To activate this feature you have to enable it
     via the new 'lbr' call-graph recording option:

        perf record --call-graph lbr
        perf report

     or:

        perf top --call-graph lbr

     This hardware feature is a lot faster than stack walk or dwarf
     based unwinding, but has some limitations:

       - It reuses the current LBR facility, so LBR call stack and
         branch record can not be enabled at the same time.

       - It is only available for user-space callchains.

     (Yan, Zheng)

   - x86 Intel Broadwell CPU support and various event constraints and
     event table fixes for earlier models.

     (Andi Kleen)

   - x86 Intel HT CPUs event scheduling workarounds.  This is a complex
     CPU bug affecting the SNB,IVB,HSW families that results in counter
     value corruption.  The mitigation code is automatically enabled and
     is transparent.

     (Maria Dimakopoulou, Stephane Eranian)

  The perf tooling side had a ton of changes in this cycle as well, so
  I'm only able to list the user visible changes here, in addition to
  the tooling changes outlined above:

  User visible changes affecting all tools:

      - Improve support of compressed kernel modules (Jiri Olsa)
      - Save DSO loading errno to better report errors (Arnaldo Carvalho de Melo)
      - Bash completion for subcommands (Yunlong Song)
      - Add 'I' event modifier for perf_event_attr.exclude_idle bit (Jiri Olsa)
      - Support missing -f to override perf.data file ownership. (Yunlong Song)
      - Show the first event with an invalid filter (David Ahern, Arnaldo Carvalho de Melo)

  User visible changes in individual tools:

    'perf data':

        New tool for converting perf.data to other formats, initially
        for the CTF (Common Trace Format) from LTTng (Jiri Olsa,
        Sebastian Siewior)

    'perf diff':

        Add --kallsyms option (David Ahern)

    'perf list':

        Allow listing events with 'tracepoint' prefix (Yunlong Song)

        Sort the output of the command (Yunlong Song)

    'perf kmem':

        Respect -i option (Jiri Olsa)

        Print big numbers using thousands' group (Namhyung Kim)

        Allow -v option (Namhyung Kim)

        Fix alignment of slab result table (Namhyung Kim)

    'perf probe':

        Support multiple probes on different binaries on the same command line (Masami Hiramatsu)

        Support unnamed union/structure members data collection. (Masami Hiramatsu)

        Check kprobes blacklist when adding new events. (Masami Hiramatsu)

    'perf record':

        Teach 'perf record' about perf_event_attr.clockid (Peter Zijlstra)

        Support recording running/enabled time (Andi Kleen)

    'perf sched':

        Improve the performance of 'perf sched replay' on high CPU core count machines (Yunlong Song)

    'perf report' and 'perf top':

        Allow annotating entries in callchains in the hists browser (Arnaldo Carvalho de Melo)

        Indicate which callchain entries are annotated in the
        TUI hists browser (Arnaldo Carvalho de Melo)

        Add pid/tid filtering to 'report' and 'script' commands (David Ahern)

        Consider PERF_RECORD_ events with cpumode == 0 in 'perf top', removing one
        cause of long term memory usage buildup, i.e. not processing PERF_RECORD_EXIT
        events (Arnaldo Carvalho de Melo)

    'perf stat':

        Report unsupported events properly (Suzuki K. Poulose)

        Output running time and run/enabled ratio in CSV mode (Andi Kleen)

    'perf trace':

        Handle legacy syscalls tracepoints (David Ahern, Arnaldo Carvalho de Melo)

        Only insert blank duration bracket when tracing syscalls (Arnaldo Carvalho de Melo)

        Filter out the trace pid when no threads are specified (Arnaldo Carvalho de Melo)

        Dump stack on segfaults (Arnaldo Carvalho de Melo)

        No need to explicitely enable evsels for workload started from perf, let it
        be enabled via perf_event_attr.enable_on_exec, removing some events that take
        place in the 'perf trace' before a workload is really started by it.
        (Arnaldo Carvalho de Melo)

        Allow mixing with tracepoints and suppressing plain syscalls. (Arnaldo Carvalho de Melo)

  There's also been a ton of infrastructure work done, such as the
  split-out of perf's build system into tools/build/ and other changes -
  see the shortlog and changelog for details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (358 commits)
  perf/x86/intel/pt: Clean up the control flow in pt_pmu_hw_init()
  perf evlist: Fix type for references to data_head/tail
  perf probe: Check the orphaned -x option
  perf probe: Support multiple probes on different binaries
  perf buildid-list: Fix segfault when show DSOs with hits
  perf tools: Fix cross-endian analysis
  perf tools: Fix error path to do closedir() when synthesizing threads
  perf tools: Fix synthesizing fork_event.ppid for non-main thread
  perf tools: Add 'I' event modifier for exclude_idle bit
  perf report: Don't call map__kmap if map is NULL.
  perf tests: Fix attr tests
  perf probe: Fix ARM 32 building error
  perf tools: Merge all perf_event_attr print functions
  perf record: Add clockid parameter
  perf sched replay: Use replay_repeat to calculate the runavg of cpu usage instead of the default value 10
  perf sched replay: Support using -f to override perf.data file ownership
  perf sched replay: Fix the EMFILE error caused by the limitation of the maximum open files
  perf sched replay: Handle the dead halt of sem_wait when create_tasks() fails for any task
  perf sched replay: Fix the segmentation fault problem caused by pr_err in threads
  perf sched replay: Realloc the memory of pid_to_task stepwise to adapt to the different pid_max configurations
  ...
2015-04-14 14:37:47 -07:00
Linus Torvalds 078838d565 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU changes from Ingo Molnar:
 "The main changes in this cycle were:

   - changes permitting use of call_rcu() and friends very early in
     boot, for example, before rcu_init() is invoked.

   - add in-kernel API to enable and disable expediting of normal RCU
     grace periods.

   - improve RCU's handling of (hotplug-) outgoing CPUs.

   - NO_HZ_FULL_SYSIDLE fixes.

   - tiny-RCU updates to make it more tiny.

   - documentation updates.

   - miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  cpu: Provide smpboot_thread_init() on !CONFIG_SMP kernels as well
  cpu: Defer smpboot kthread unparking until CPU known to scheduler
  rcu: Associate quiescent-state reports with grace period
  rcu: Yet another fix for preemption and CPU hotplug
  rcu: Add diagnostics to grace-period cleanup
  rcutorture: Default to grace-period-initialization delays
  rcu: Handle outgoing CPUs on exit from idle loop
  cpu: Make CPU-offline idle-loop transition point more precise
  rcu: Eliminate ->onoff_mutex from rcu_node structure
  rcu: Process offlining and onlining only at grace-period start
  rcu: Move rcu_report_unblock_qs_rnp() to common code
  rcu: Rework preemptible expedited bitmask handling
  rcu: Remove event tracing from rcu_cpu_notify(), used by offline CPUs
  rcutorture: Enable slow grace-period initializations
  rcu: Provide diagnostic option to slow down grace-period initialization
  rcu: Detect stalls caused by failure to propagate up rcu_node tree
  rcu: Eliminate empty HOTPLUG_CPU ifdef
  rcu: Simplify sync_rcu_preempt_exp_init()
  rcu: Put all orphan-callback-related code under same comment
  rcu: Consolidate offline-CPU callback initialization
  ...
2015-04-14 13:36:04 -07:00
Linus Torvalds d0bbe0dd35 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree from Jiri Kosina:
 "Usual trivial tree updates.  Nothing outstanding -- mostly printk()
  and comment fixes and unused identifier removals"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  goldfish: goldfish_tty_probe() is not using 'i' any more
  powerpc: Fix comment in smu.h
  qla2xxx: Fix printks in ql_log message
  lib: correct link to the original source for div64_u64
  si2168, tda10071, m88ds3103: Fix firmware wording
  usb: storage: Fix printk in isd200_log_config()
  qla2xxx: Fix printk in qla25xx_setup_mode
  init/main: fix reset_device comment
  ipwireless: missing assignment
  goldfish: remove unreachable line of code
  coredump: Fix do_coredump() comment
  stacktrace.h: remove duplicate declaration task_struct
  smpboot.h: Remove unused function prototype
  treewide: Fix typo in printk messages
  treewide: Fix typo in printk messages
  mod_devicetable: fix comment for match_flags
2015-04-14 09:50:27 -07:00
Paul E. McKenney 00df35f991 cpu: Defer smpboot kthread unparking until CPU known to scheduler
Currently, smpboot_unpark_threads() is invoked before the incoming CPU
has been added to the scheduler's runqueue structures.  This might
potentially cause the unparked kthread to run on the wrong CPU, since the
correct CPU isn't fully set up yet.

That causes a sporadic, hard to debug boot crash triggering on some
systems, reported by Borislav Petkov, and bisected down to:

  2a442c9c64 ("x86: Use common outgoing-CPU-notification code")

This patch places smpboot_unpark_threads() in a CPU hotplug
notifier with priority set so that these kthreads are unparked just after
the CPU has been added to the runqueues.

Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-13 08:25:16 +02:00
Vladimir Davydov 197175427a Documentation/memcg: update memcg/kmem status
Memcg/kmem reclaim support has been finally merged. Reflect this in the
documentation.

Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-11 15:23:31 +02:00
Ingo Molnar e1abf2cc8d bpf: Fix the build on BPF_SYSCALL=y && !CONFIG_TRACING kernels, make it more configurable
So bpf_tracing.o depends on CONFIG_BPF_SYSCALL - but that's not its only
dependency, it also depends on the tracing infrastructure and on kprobes,
without which it will fail to build with:

  In file included from kernel/trace/bpf_trace.c:14:0:
  kernel/trace/trace.h: In function ‘trace_test_and_set_recursion’:
  kernel/trace/trace.h:491:28: error: ‘struct task_struct’ has no member named ‘trace_recursion’
    unsigned int val = current->trace_recursion;
  [...]

It took quite some time to trigger this build failure, because right now
BPF_SYSCALL is very obscure, depends on CONFIG_EXPERT. So also make BPF_SYSCALL
more configurable, not just under CONFIG_EXPERT.

If BPF_SYSCALL, tracing and kprobes are enabled then enable the bpf_tracing
gateway as well.

We might want to make this an interactive option later on, although
I'd not complicate it unnecessarily: enabling BPF_SYSCALL is enough of
an indicator that the user wants BPF support.

Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-02 16:28:06 +02:00
Frans Klaver fc454fdc10 init/main: fix reset_device comment
Fix incorrect spelling of situation.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-03-06 23:12:43 +01:00
Zefan Li 695df2132c cpuset: initialize cpuset a bit early
Now we call ss->bind() in cgroup_init(), so cgroup_init() will
call cpuset_bind() and then the latter will access top_cpuset's
cpumask, which is NULL, because cpuset_init() is called after
cgroup_init()

The simplest fix is to swap cgroup_init() and cpuset_init().

Cc: Vladimir Davydov <vdavydov@parallels.com>
Fixes: 295458e672 ("cgroup: call cgroup_subsys->bind on cgroup subsys initialization")
Reported by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vladimir Davydov <vdavydov@parallels.com>
2015-03-05 08:05:20 -05:00