Pull workqueue updates from Tejun Heo:
"rcu_work addition and a couple trivial changes"
* 'for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: remove the comment about the old manager_arb mutex
workqueue: fix the comments of nr_idle
fs/aio: Use rcu_work instead of explicit rcu and work item
cgroup: Use rcu_work instead of explicit rcu and work item
RCU, workqueue: Implement rcu_work
Since the worker rebinding behavior was refactored, there is
no idle worker off the idle_list now. The comment is outdated
and can be just removed.
It also groups nr_workers and nr_idle together.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
There are cases where RCU callback needs to be bounced to a sleepable
context. This is currently done by the RCU callback queueing a work
item, which can be cumbersome to write and confusing to read.
This patch introduces rcu_work, a workqueue work variant which gets
executed after a RCU grace period, and converts the open coded
bouncing in fs/aio and kernel/cgroup.
v3: Dropped queue_rcu_work_on(). Documented rcu grace period behavior
after queue_rcu_work().
v2: Use rcu_barrier() instead of synchronize_rcu() to wait for
completion of previously queued rcu callback as per Paul.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Found this by accident.
There are no usages of bare cancel_work() in current kernel source.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Never directly free @dev after calling device_register(), even
if it returned an error! Always use put_device() to give up the
reference initialized in this function instead.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
* tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc:
drm/tve200: fix kernel-doc documentation comment include
drm/meson: fix vsync buffer update
drm: Handle unexpected holes in color-eviction
drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
drm/amdgpu: Fix deadlock on runtime suspend
drm/radeon: Fix deadlock on runtime suspend
drm/nouveau: Fix deadlock on runtime suspend
drm: Allow determining if current task is output poll worker
workqueue: Allow retrieval of current task's work struct
drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits
Pull staging/IIO updates from Greg KH:
"Here is the big Staging and IIO driver patches for 4.16-rc1.
There is the normal amount of new IIO drivers added, like all
releases.
The networking IPX and the ncpfs filesystem are moved into the staging
tree, as they are on their way out of the kernel due to lack of use
anymore.
The visorbus subsystem finall has started moving out of the staging
tree to the "real" part of the kernel, and the most and fsl-mc
codebases are almost ready to move out, that will probably happen for
4.17-rc1 if all goes well.
Other than that, there is a bunch of license header cleanups in the
tree, along with the normal amount of coding style churn that we all
know and love for this codebase. I also got frustrated at the
Meltdown/Spectre mess and took it out on the dgnc tty driver, deleting
huge chunks of it that were never even being used.
Full details of everything is in the shortlog.
All of these patches have been in linux-next for a while with no
reported issues"
* tag 'staging-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (627 commits)
staging: rtlwifi: remove redundant initialization of 'cfg_cmd'
staging: rtl8723bs: remove a couple of redundant initializations
staging: comedi: reformat lines to 80 chars or less
staging: lustre: separate a connection destroy from free struct kib_conn
Staging: rtl8723bs: Use !x instead of NULL comparison
Staging: rtl8723bs: Remove dead code
Staging: rtl8723bs: Change names to conform to the kernel code
staging: ccree: Fix missing blank line after declaration
staging: rtl8188eu: remove redundant initialization of 'pwrcfgcmd'
staging: rtlwifi: remove unused RTLHALMAC_ST and RTLPHYDM_ST
staging: fbtft: remove unused FB_TFT_SSD1325 kconfig
staging: comedi: dt2811: remove redundant initialization of 'ns'
staging: wilc1000: fix alignments to match open parenthesis
staging: wilc1000: removed unnecessary defined enums typedef
staging: wilc1000: remove unnecessary use of parentheses
staging: rtl8192u: remove redundant initialization of 'timeout'
staging: sm750fb: fix CamelCase for dispSet var
staging: lustre: lnet/selftest: fix compile error on UP build
staging: rtl8723bs: hal_com_phycfg: Remove unneeded semicolons
staging: rts5208: Fix "seg_no" calculation in reset_ms_card()
...
Pull workqueue updates from Tejun Heo:
"Workqueue has an early init trick where workqueues can be created and
work items queued on them before the workqueue subsystem is online.
This helps simplifying early init and operation of low level
subsystems which use workqueues for managerial things which aren't
depended upon early during boot.
Out of laziness, the early init didn't cover workqueues with
WQ_MEM_RECLAIM, which is inconsistent and confusing because adding the
flag simply makes the system fail to boot. Cover WQ_MEM_RECLAIM too.
This was originally brought up for RCU but RCU didn't actually need
this. I still think it's a good idea to cover it"
* 'for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: allow WQ_MEM_RECLAIM on early init workqueues
workqueue: separate out init_rescuer()
Pull RCU updates from Ingo Molnar:
"The main RCU changes in this cycle were:
- Updates to use cond_resched() instead of cond_resched_rcu_qs()
where feasible (currently everywhere except in kernel/rcu and in
kernel/torture.c). Also a couple of fixes to avoid sending IPIs to
offline CPUs.
- Updates to simplify RCU's dyntick-idle handling.
- Updates to remove almost all uses of smp_read_barrier_depends() and
read_barrier_depends().
- Torture-test updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
torture: Save a line in stutter_wait(): while -> for
torture: Eliminate torture_runnable and perf_runnable
torture: Make stutter less vulnerable to compilers and races
locking/locktorture: Fix num reader/writer corner cases
locking/locktorture: Fix rwsem reader_delay
torture: Place all torture-test modules in one MAINTAINERS group
rcutorture/kvm-build.sh: Skip build directory check
rcutorture: Simplify functions.sh include path
rcutorture: Simplify logging
rcutorture/kvm-recheck-*: Improve result directory readability check
rcutorture/kvm.sh: Support execution from any directory
rcutorture/kvm.sh: Use consistent help text for --qemu-args
rcutorture/kvm.sh: Remove unused variable, `alldone`
rcutorture: Remove unused script, config2frag.sh
rcutorture/configinit: Fix build directory error message
rcutorture: Preempt RCU-preempt readers more vigorously
torture: Reduce #ifdefs for preempt_schedule()
rcu: Remove have_rcu_nocb_mask from tree_plugin.h
rcu: Add comment giving debug strategy for double call_rcu()
tracing, rcu: Hide trace event rcu_nocb_wake when not used
...
Instead of the cfs workitem library, use workqueues.
As lnet wants to provide a cpu mask of allowed cpus, it
needs to be a WQ_UNBOUND work queue so that tasks can
run on cpus other than where they were submitted.
This patch also exported apply_workqueue_attrs() which is
a documented part of the workqueue API, that isn't currently
exported. lustre needs it to allow workqueue thread to be limited
to a subset of CPUs.
Acked-by: Tejun Heo <tj@kernel.org> (for export of apply_workqueue_attrs)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
show_workqueue_state() can print out a lot of messages while being in
atomic context, e.g. sysrq-t -> show_workqueue_state(). If the console
device is slow it may end up triggering NMI hard lockup watchdog.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v4.5+
Workqueues can be created early during boot before workqueue subsystem
in fully online - work items are queued waiting for later full
initialization. However, early init wasn't supported for
WQ_MEM_RECLAIM workqueues causing unnecessary annoyances for a subset
of users. Expand early init support to include WQ_MEM_RECLAIM
workqueues.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Separate out init_rescuer() from __alloc_workqueue_key() to prepare
for early init support for WQ_MEM_RECLAIM. This patch doesn't
introduce any functional changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Pull RCU updates from Paul E. McKenney:
- Updates to use cond_resched() instead of cond_resched_rcu_qs()
where feasible (currently everywhere except in kernel/rcu and
in kernel/torture.c). Also a couple of fixes to avoid sending
IPIs to offline CPUs.
- Updates to simplify RCU's dyntick-idle handling.
- Updates to remove almost all uses of smp_read_barrier_depends()
and read_barrier_depends().
- Miscellaneous fixes.
- Torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the cpu/hotplug refactoring, DOWN_FAILED is never called without
preceding DOWN_PREPARE making the workaround unnecessary. Remove it.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Initialize wq_unbound_cpumask to exclude cpus that were isolated by
the cmdline's isolcpus parameter.
Signed-off-by: Tal Shorer <tal.shorer@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
With all callbacks converted, and the timer callback prototype
switched over, the TIMER_FUNC_TYPE cast is no longer needed,
so remove it. Conversion was done with the following scripts:
perl -pi -e 's|\(TIMER_FUNC_TYPE\)||g' \
$(git grep TIMER_FUNC_TYPE | cut -d: -f1 | sort -u)
perl -pi -e 's|\(TIMER_DATA_TYPE\)||g' \
$(git grep TIMER_DATA_TYPE | cut -d: -f1 | sort -u)
The now unused macros are also dropped from include/linux/timer.h.
Signed-off-by: Kees Cook <keescook@chromium.org>
