Commit Graph

727 Commits

Author SHA1 Message Date
Linus Torvalds
8f98f6f5d6 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two fixes:

   - a SCHED_DEADLINE task selection fix
   - a sched/numa related lockdep splat fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Check for stop task appearance when balancing happens
  sched/numa: Fix task_numa_free() lockdep splat
2014-04-19 10:40:51 -07:00
Kirill Tkhai
a1d9a3231e sched: Check for stop task appearance when balancing happens
We need to do it like we do for the other higher priority classes..

Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Cc: Michael wang <wangyun@linux.vnet.ibm.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/336561397137116@web27h.yandex.ru
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-17 13:39:51 +02:00
Mike Galbraith
60e69eed85 sched/numa: Fix task_numa_free() lockdep splat
Sasha reported that lockdep claims that the following commit:
made numa_group.lock interrupt unsafe:

  156654f491 ("sched/numa: Move task_numa_free() to __put_task_struct()")

While I don't see how that could be, given the commit in question moved
task_numa_free() from one irq enabled region to another, the below does
make both gripes and lockups upon gripe with numa=fake=4 go away.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Fixes: 156654f491 ("sched/numa: Move task_numa_free() to __put_task_struct()")
Signed-off-by: Mike Galbraith <bitbucket@online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: torvalds@linux-foundation.org
Cc: mgorman@suse.com
Cc: akpm@linux-foundation.org
Cc: Dave Jones <davej@redhat.com>
Link: http://lkml.kernel.org/r/1396860915.5170.5.camel@marge.simpson.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-11 10:39:15 +02:00
Linus Torvalds
26c12d9334 Merge branch 'akpm' (incoming from Andrew)
Merge second patch-bomb from Andrew Morton:
 - the rest of MM
 - zram updates
 - zswap updates
 - exit
 - procfs
 - exec
 - wait
 - crash dump
 - lib/idr
 - rapidio
 - adfs, affs, bfs, ufs
 - cris
 - Kconfig things
 - initramfs
 - small amount of IPC material
 - percpu enhancements
 - early ioremap support
 - various other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (156 commits)
  MAINTAINERS: update Intel C600 SAS driver maintainers
  fs/ufs: remove unused ufs_super_block_third pointer
  fs/ufs: remove unused ufs_super_block_second pointer
  fs/ufs: remove unused ufs_super_block_first pointer
  fs/ufs/super.c: add __init to init_inodecache()
  doc/kernel-parameters.txt: add early_ioremap_debug
  arm64: add early_ioremap support
  arm64: initialize pgprot info earlier in boot
  x86: use generic early_ioremap
  mm: create generic early_ioremap() support
  x86/mm: sparse warning fix for early_memremap
  lglock: map to spinlock when !CONFIG_SMP
  percpu: add preemption checks to __this_cpu ops
  vmstat: use raw_cpu_ops to avoid false positives on preemption checks
  slub: use raw_cpu_inc for incrementing statistics
  net: replace __this_cpu_inc in route.c with raw_cpu_inc
  modules: use raw_cpu_write for initialization of per cpu refcount.
  mm: use raw_cpu ops for determining current NUMA node
  percpu: add raw_cpu_ops
  slub: fix leak of 'name' in sysfs_slab_add
  ...
2014-04-07 16:38:06 -07:00
Gideon Israel Dsouza
52f5684c8e kernel: use macros from compiler.h instead of __attribute__((...))
To increase compiler portability there is <linux/compiler.h> which
provides convenience macros for various gcc constructs.  Eg: __weak for
__attribute__((weak)).  I've replaced all instances of gcc attributes
with the right macro in the kernel subsystem.

Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:11 -07:00
Arnd Bergmann
b8780c363d sched: remove sleep_on() and friends
This is the final piece in the puzzle, as all patches to remove the
last users of \(interruptible_\|\)sleep_on\(_timeout\|\) have made it
into the 3.15 merge window. The work was long overdue, and this
interface in particular should not have survived the BKL removal
that was done a couple of years ago.

Citing Jon Corbet from http://lwn.net/2001/0201/kernel.php3":

 "[...] it was suggested that the janitors look for and fix all code
  that calls sleep_on() [...] since (1) almost all such code is
  incorrect, and (2) Linus has agreed that those functions should
  be removed in the 2.5 development series".

We haven't quite made it for 2.5, but maybe we can merge this for 3.15.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 11:24:06 -07:00
Linus Torvalds
76ca7d1cca Merge branch 'akpm' (incoming from Andrew)
Merge first patch-bomb from Andrew Morton:
 - Various misc bits
 - kmemleak fixes
 - small befs, codafs, cifs, efs, freexxfs, hfsplus, minixfs, reiserfs things
 - fanotify
 - I appear to have become SuperH maintainer
 - ocfs2 updates
 - direct-io tweaks
 - a bit of the MM queue
 - printk updates
 - MAINTAINERS maintenance
 - some backlight things
 - lib/ updates
 - checkpatch updates
 - the rtc queue
 - nilfs2 updates
 - Small Documentation/ updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (237 commits)
  Documentation/SubmittingPatches: remove references to patch-scripts
  Documentation/SubmittingPatches: update some dead URLs
  Documentation/filesystems/ntfs.txt: remove changelog reference
  Documentation/kmemleak.txt: updates
  fs/reiserfs/super.c: add __init to init_inodecache
  fs/reiserfs: move prototype declaration to header file
  fs/hfsplus/attributes.c: add __init to hfsplus_create_attr_tree_cache()
  fs/hfsplus/extents.c: fix concurrent acess of alloc_blocks
  fs/hfsplus/extents.c: remove unused variable in hfsplus_get_block
  nilfs2: update project's web site in nilfs2.txt
  nilfs2: update MAINTAINERS file entries fix
  nilfs2: verify metadata sizes read from disk
  nilfs2: add FITRIM ioctl support for nilfs2
  nilfs2: add nilfs_sufile_trim_fs to trim clean segs
  nilfs2: implementation of NILFS_IOCTL_SET_SUINFO ioctl
  nilfs2: add nilfs_sufile_set_suinfo to update segment usage
  nilfs2: add struct nilfs_suinfo_update and flags
  nilfs2: update MAINTAINERS file entries
  fs/coda/inode.c: add __init to init_inodecache()
  BEFS: logging cleanup
  ...
2014-04-03 16:22:16 -07:00
Paul Gortmaker
c96d6660dc kernel: audit/fix non-modular users of module_init in core code
Code that is obj-y (always built-in) or dependent on a bool Kconfig
(built-in or absent) can never be modular.  So using module_init as an
alias for __initcall can be somewhat misleading.

Fix these up now, so that we can relocate module_init from init.h into
module.h in the future.  If we don't do this, we'd have to add module.h
to obviously non-modular code, and that would be a worse thing.

The audit targets the following module_init users for change:
 kernel/user.c                  obj-y
 kernel/kexec.c                 bool KEXEC (one instance per arch)
 kernel/profile.c               bool PROFILING
 kernel/hung_task.c             bool DETECT_HUNG_TASK
 kernel/sched/stats.c           bool SCHEDSTATS
 kernel/user_namespace.c        bool USER_NS

Note that direct use of __initcall is discouraged, vs.  one of the
priority categorized subgroups.  As __initcall gets mapped onto
device_initcall, our use of subsys_initcall (which makes sense for these
files) will thus change this registration from level 6-device to level
4-subsys (i.e.  slightly earlier).  However no observable impact of that
difference has been observed during testing.

Also, two instances of missing ";" at EOL are fixed in kexec.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:07 -07:00
Linus Torvalds
32d01dc7be Merge branch 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "A lot updates for cgroup:

   - The biggest one is cgroup's conversion to kernfs.  cgroup took
     after the long abandoned vfs-entangled sysfs implementation and
     made it even more convoluted over time.  cgroup's internal objects
     were fused with vfs objects which also brought in vfs locking and
     object lifetime rules.  Naturally, there are places where vfs rules
     don't fit and nasty hacks, such as credential switching or lock
     dance interleaving inode mutex and cgroup_mutex with object serial
     number comparison thrown in to decide whether the operation is
     actually necessary, needed to be employed.

     After conversion to kernfs, internal object lifetime and locking
     rules are mostly isolated from vfs interactions allowing shedding
     of several nasty hacks and overall simplification.  This will also
     allow implmentation of operations which may affect multiple cgroups
     which weren't possible before as it would have required nesting
     i_mutexes.

   - Various simplifications including dropping of module support,
     easier cgroup name/path handling, simplified cgroup file type
     handling and task_cg_lists optimization.

   - Prepatory changes for the planned unified hierarchy, which is still
     a patchset away from being actually operational.  The dummy
     hierarchy is updated to serve as the default unified hierarchy.
     Controllers which aren't claimed by other hierarchies are
     associated with it, which BTW was what the dummy hierarchy was for
     anyway.

   - Various fixes from Li and others.  This pull request includes some
     patches to add missing slab.h to various subsystems.  This was
     triggered xattr.h include removal from cgroup.h.  cgroup.h
     indirectly got included a lot of files which brought in xattr.h
     which brought in slab.h.

  There are several merge commits - one to pull in kernfs updates
  necessary for converting cgroup (already in upstream through
  driver-core), others for interfering changes in the fixes branch"

* 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (74 commits)
  cgroup: remove useless argument from cgroup_exit()
  cgroup: fix spurious lockdep warning in cgroup_exit()
  cgroup: Use RCU_INIT_POINTER(x, NULL) in cgroup.c
  cgroup: break kernfs active_ref protection in cgroup directory operations
  cgroup: fix cgroup_taskset walking order
  cgroup: implement CFTYPE_ONLY_ON_DFL
  cgroup: make cgrp_dfl_root mountable
  cgroup: drop const from @buffer of cftype->write_string()
  cgroup: rename cgroup_dummy_root and related names
  cgroup: move ->subsys_mask from cgroupfs_root to cgroup
  cgroup: treat cgroup_dummy_root as an equivalent hierarchy during rebinding
  cgroup: remove NULL checks from [pr_cont_]cgroup_{name|path}()
  cgroup: use cgroup_setup_root() to initialize cgroup_dummy_root
  cgroup: reorganize cgroup bootstrapping
  cgroup: relocate setting of CGRP_DEAD
  cpuset: use rcu_read_lock() to protect task_cs()
  cgroup_freezer: document freezer_fork() subtleties
  cgroup: update cgroup_transfer_tasks() to either succeed or fail
  cgroup: drop task_lock() protection around task->cgroups
  cgroup: update how a newly forked task gets associated with css_set
  ...
2014-04-03 13:05:42 -07:00
Linus Torvalds
05bf58ca4b Merge branch 'sched-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched/idle changes from Ingo Molnar:
 "More idle code reorganization, to prepare for more integration.

  (Sent separately because it depended on pending timer work, which is
  now upstream)"

* 'sched-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/idle: Add more comments to the code
  sched/idle: Move idle conditions in cpuidle_idle main function
  sched/idle: Reorganize the idle loop
  cpuidle/idle: Move the cpuidle_idle_call function to idle.c
  idle/cpuidle: Split cpuidle_idle_call main function into smaller functions
2014-04-02 16:22:27 -07:00
Linus Torvalds
7a48837732 Merge branch 'for-3.15/core' of git://git.kernel.dk/linux-block
Pull core block layer updates from Jens Axboe:
 "This is the pull request for the core block IO bits for the 3.15
  kernel.  It's a smaller round this time, it contains:

   - Various little blk-mq fixes and additions from Christoph and
     myself.

   - Cleanup of the IPI usage from the block layer, and associated
     helper code.  From Frederic Weisbecker and Jan Kara.

   - Duplicate code cleanup in bio-integrity from Gu Zheng.  This will
     give you a merge conflict, but that should be easy to resolve.

   - blk-mq notify spinlock fix for RT from Mike Galbraith.

   - A blktrace partial accounting bug fix from Roman Pen.

   - Missing REQ_SYNC detection fix for blk-mq from Shaohua Li"

* 'for-3.15/core' of git://git.kernel.dk/linux-block: (25 commits)
  blk-mq: add REQ_SYNC early
  rt,blk,mq: Make blk_mq_cpu_notify_lock a raw spinlock
  blk-mq: support partial I/O completions
  blk-mq: merge blk_mq_insert_request and blk_mq_run_request
  blk-mq: remove blk_mq_alloc_rq
  blk-mq: don't dump CPU -> hw queue map on driver load
  blk-mq: fix wrong usage of hctx->state vs hctx->flags
  blk-mq: allow blk_mq_init_commands() to return failure
  block: remove old blk_iopoll_enabled variable
  blktrace: fix accounting of partially completed requests
  smp: Rename __smp_call_function_single() to smp_call_function_single_async()
  smp: Remove wait argument from __smp_call_function_single()
  watchdog: Simplify a little the IPI call
  smp: Move __smp_call_function_single() below its safe version
  smp: Consolidate the various smp_call_function_single() declensions
  smp: Teach __smp_call_function_single() to check for offline cpus
  smp: Remove unused list_head from csd
  smp: Iterate functions through llist_for_each_entry_safe()
  block: Stop abusing rq->csd.list in blk-softirq
  block: Remove useless IPI struct initialization
  ...
2014-04-01 19:19:15 -07:00
Linus Torvalds
1ead658124 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer changes from Thomas Gleixner:
 "This assorted collection provides:

   - A new timer based timer broadcast feature for systems which do not
     provide a global accessible timer device.  That allows those
     systems to put CPUs into deep idle states where the per cpu timer
     device stops.

   - A few NOHZ_FULL related improvements to the timer wheel

   - The usual updates to timer devices found in ARM SoCs

   - Small improvements and updates all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  tick: Remove code duplication in tick_handle_periodic()
  tick: Fix spelling mistake in tick_handle_periodic()
  x86: hpet: Use proper destructor for delayed work
  workqueue: Provide destroy_delayed_work_on_stack()
  clocksource: CMT, MTU2, TMU and STI should depend on GENERIC_CLOCKEVENTS
  timer: Remove code redundancy while calling get_nohz_timer_target()
  hrtimer: Rearrange comments in the order struct members are declared
  timer: Use variable head instead of &work_list in __run_timers()
  clocksource: exynos_mct: silence a static checker warning
  arm: zynq: Add support for cpufreq
  arm: zynq: Don't use arm_global_timer with cpufreq
  clocksource/cadence_ttc: Overhaul clocksource frequency adjustment
  clocksource/cadence_ttc: Call clockevents_update_freq() with IRQs enabled
  clocksource: Add Kconfig entries for CMT, MTU2, TMU and STI
  sh: Remove Kconfig entries for TMU, CMT and MTU2
  ARM: shmobile: Remove CMT, TMU and STI Kconfig entries
  clocksource: armada-370-xp: Use atomic access for shared registers
  clocksource: orion: Use atomic access for shared registers
  clocksource: timer-keystone: Delete unnecessary variable
  clocksource: timer-keystone: introduce clocksource driver for Keystone
  ...
2014-04-01 11:00:07 -07:00
Linus Torvalds
a21e40877a Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Ingo Molnar:
 "The main purpose is to fix a full dynticks bug related to
  virtualization, where steal time accounting appears to be zero in
  /proc/stat even after a few seconds of competing guests running busy
  loops in a same host CPU.  It's not a regression though as it was
  there since the beginning.

  The other commits are preparatory work to fix the bug and various
  cleanups"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arch: Remove stub cputime.h headers
  sched: Remove needless round trip nsecs <-> tick conversion of steal time
  cputime: Fix jiffies based cputime assumption on steal accounting
  cputime: Bring cputime -> nsecs conversion
  cputime: Default implementation of nsecs -> cputime conversion
  cputime: Fix nsecs_to_cputime() return type cast
2014-04-01 10:16:10 -07:00
Linus Torvalds
1f8c538ed6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "There are two memory management related changes, the CMMA support for
  KVM to avoid swap-in of freed pages and the split page table lock for
  the PMD level.  These two come with common code changes in mm/.

  A fix for the long standing theoretical TLB flush problem, this one
  comes with a common code change in kernel/sched/.

  Another set of changes is Heikos uaccess work, included is the initial
  set of patches with more to come.

  And fixes and cleanups as usual"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (36 commits)
  s390/con3270: optionally disable auto update
  s390/mm: remove unecessary parameter from pgste_ipte_notify
  s390/mm: remove unnecessary parameter from gmap_do_ipte_notify
  s390/mm: fixing comment so that parameter name match
  s390/smp: limit number of cpus in possible cpu mask
  hypfs: Add clarification for "weight_min" attribute
  s390: update defconfigs
  s390/ptrace: add support for PTRACE_SINGLEBLOCK
  s390/perf: make print_debug_cf() static
  s390/topology: Remove call to update_cpu_masks()
  s390/compat: remove compat exec domain
  s390: select CONFIG_TTY for use of tty in unconditional keyboard driver
  s390/appldata_os: fix cpu array size calculation
  s390/checksum: remove memset() within csum_partial_copy_from_user()
  s390/uaccess: remove copy_from_user_real()
  s390/sclp_early: Return correct HSA block count also for zero
  s390: add some drivers/subsystems to the MAINTAINERS file
  s390: improve debug feature usage
  s390/airq: add support for irq ranges
  s390/mm: enable split page table lock for PMD level
  ...
2014-03-31 14:35:30 -07:00
Viresh Kumar
6201b4d61f timer: Remove code redundancy while calling get_nohz_timer_target()
There are only two users of get_nohz_timer_target(): timer and hrtimer. Both
call it under same circumstances, i.e.

	#ifdef CONFIG_NO_HZ_COMMON
	       if (!pinned && get_sysctl_timer_migration() && idle_cpu(this_cpu))
	               return get_nohz_timer_target();
	#endif

So, it makes more sense to get all this as part of get_nohz_timer_target()
instead of duplicating code at two places. For this another parameter is
required to be passed to this routine, pinned.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1e1b53537217d58d48c2d7a222a9c3ac47d5b64c.1395140107.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-20 12:35:46 +01:00
Frederic Weisbecker
300a9d887e sched: Remove needless round trip nsecs <-> tick conversion of steal time
When update_rq_clock_task() accounts the pending steal time for a task,
it converts the steal delta from nsecs to tick then from tick to nsecs.

There is no apparent good reason for doing that though because both
the task clock and the prev steal delta are u64 and store values
in nsecs.

So lets remove the needless conversion.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-03-13 15:56:44 +01:00
Frederic Weisbecker
dee08a72de cputime: Fix jiffies based cputime assumption on steal accounting
The steal guest time accounting code assumes that cputime_t is based on
jiffies. So when CONFIG_NO_HZ_FULL=y, which implies that cputime_t
is based on nsecs, steal_account_process_tick() passes the delta in
jiffies to account_steal_time() which then accounts it as if it's a
value in nsecs.

As a result, accounting 1 second of steal time (with HZ=100 that would
be 100 jiffies) is spuriously accounted as 100 nsecs.

As such /proc/stat may report 0 values of steal time even when two
guests have run concurrently for a few seconds on the same host and
same CPU.

In order to fix this, lets convert the nsecs based steal delta to
cputime instead of jiffies by using the right conversion API.

Given that the steal time is stored in cputime_t and this type can have
a smaller granularity than nsecs, we only account the rounded converted
value and leave the remaining nsecs for the next deltas.

Reported-by: Huiqingding <huding@redhat.com>
Reported-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-03-13 15:56:44 +01:00
Alex Shi
6037dd1a49 sched: Clean up the task_hot() function
task_hot() doesn't need the 'sched_domain' parameter, so remove it.

Signed-off-by: Alex Shi <alex.shi@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394607111-1904-1-git-send-email-alex.shi@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 10:49:01 +01:00
Vincent Guittot
a2cd42601b sched: Remove double calculation in fix_small_imbalance()
The tmp value has been already calculated in:

  scaled_busy_load_per_task =
		(busiest->load_per_task * SCHED_POWER_SCALE) /
		busiest->group_power;

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394555166-22894-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 10:49:00 +01:00
Steven Rostedt
383afd0971 sched: Fix broken setscheduler()
I decided to run my tests on linux-next, and my wakeup_rt tracer was
broken. After running a bisect, I found that the problem commit was:

   linux-next commit c365c292d0
   "sched: Consider pi boosting in setscheduler()"

And the reason the wake_rt tracer test was failing, was because it had
no RT task to trace. I first noticed this when running with
sched_switch event and saw that my RT task still had normal SCHED_OTHER
priority. Looking at the problem commit, I found:

 -       p->normal_prio = normal_prio(p);
 -       p->prio = rt_mutex_getprio(p);

With no

 +       p->normal_prio = normal_prio(p);
 +       p->prio = rt_mutex_getprio(p);

Reading what the commit is suppose to do, I realize that the p->prio
can't be set if the task is boosted with a higher prio, but the
p->normal_prio still needs to be set regardless, otherwise, when the
task is deboosted, it wont get the new priority.

The p->prio has to be set before "check_class_changed()" is called,
otherwise the class wont be changed.

Also added fix to newprio to include a check for deadline policy that
was missing. This change was suggested by Juri Lelli.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: SebastianAndrzej Siewior <bigeasy@linutronix.de>
Cc: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140306120438.638bfe94@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 10:48:59 +01:00
Mike Galbraith
156654f491 sched/numa: Move task_numa_free() to __put_task_struct()
Bad idea on -rt:

[  908.026136]  [<ffffffff8150ad6a>] rt_spin_lock_slowlock+0xaa/0x2c0
[  908.026145]  [<ffffffff8108f701>] task_numa_free+0x31/0x130
[  908.026151]  [<ffffffff8108121e>] finish_task_switch+0xce/0x100
[  908.026156]  [<ffffffff81509c0a>] thread_return+0x48/0x4ae
[  908.026160]  [<ffffffff8150a095>] schedule+0x25/0xa0
[  908.026163]  [<ffffffff8150ad95>] rt_spin_lock_slowlock+0xd5/0x2c0
[  908.026170]  [<ffffffff810658cf>] get_signal_to_deliver+0xaf/0x680
[  908.026175]  [<ffffffff8100242d>] do_signal+0x3d/0x5b0
[  908.026179]  [<ffffffff81002a30>] do_notify_resume+0x90/0xe0
[  908.026186]  [<ffffffff81513176>] int_signal+0x12/0x17
[  908.026193]  [<00007ff2a388b1d0>] 0x7ff2a388b1cf

and since upstream does not mind where we do this, be a bit nicer ...

Signed-off-by: Mike Galbraith <bitbucket@online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1393568591.6018.27.camel@marge.simpson.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:43 +01:00
Kirill Tkhai
35805ff8f4 sched/fair: Fix endless loop in idle_balance()
Check for fair tasks number to decide, that we've pulled a task.
rq's nr_running may contain throttled RT tasks.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394118975.19290.104.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:41 +01:00
Kirill Tkhai
4c6c4e38c4 sched/core: Fix endless loop in pick_next_task()
1) Single cpu machine case.

When rq has only RT tasks, but no one of them can be picked
because of throttling, we enter in endless loop.

pick_next_task_{dl,rt} return NULL.

In pick_next_task_fair() we permanently go to retry

	if (rq->nr_running != rq->cfs.h_nr_running)
		return RETRY_TASK;

(rq->nr_running is not being decremented when rt_rq becomes
throttled).

No chances to unthrottle any rt_rq or to wake fair here,
because of rq is locked permanently and interrupts are
disabled.

2) In case of SMP this can cause a hang too. Although we unlock
   rq in idle_balance(), interrupts are still disabled.

The solution is to check for available tasks in DL and RT
classes instead of checking for sum.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394098321.19290.11.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:39 +01:00
Kirill Tkhai
e4aa358b6c sched/fair: Push down check for high priority class task into idle_balance()
We close idle_exit_fair() bracket in case of we've pulled something or we've received
task of high priority class.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/1394098315.19290.10.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:37 +01:00
Kirill Tkhai
734ff2a71f sched/rt: Fix picking RT and DL tasks from empty queue
The problems:

1) We check for rt_nr_running before call of put_prev_task().
   If previous task is RT, its rt_rq may become throttled
   and dequeued after this call.

In case of p is from rt->rq this just causes picking a task
from throttled queue, but in case of its rt_rq is child
we are guaranteed catch BUG_ON.

2) The same with deadline class. The only difference we operate
   on only dl_rq.

This patch fixes all the above problems and it adds a small skip in the
DL update like we've already done for RT class:

	if (unlikely((s64)delta_exec <= 0))
		return;

This will optimize sequential update_curr_dl() calls a little.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Link: http://lkml.kernel.org/r/1393946746.3643.3.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:35 +01:00