Commit Graph

23315 Commits

Author SHA1 Message Date
Shaohua Li
b761fe226b bpf: clean up put_cpu_var usage
put_cpu_var takes the percpu data, not the data returned from
get_cpu_var.

This doesn't change the behavior.

Cc: Tejun Heo <tj@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-27 22:09:17 -04:00
Linus Torvalds
8ab293e3a1 Merge branch 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "Three late fixes for cgroup: Two cpuset ones, one trivial and the
  other pretty obscure, and a cgroup core fix for a bug which impacts
  cgroup v2 namespace users"

* 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix invalid controller enable rejections with cgroup namespace
  cpuset: fix non static symbol warning
  cpuset: handle race between CPU hotplug and cpuset_hotplug_work
2016-09-27 16:43:11 -07:00
Mickaël Salaün
1955351da4 bpf: Set register type according to is_valid_access()
This prevent future potential pointer leaks when an unprivileged eBPF
program will read a pointer value from its context. Even if
is_valid_access() returns a pointer type, the eBPF verifier replace it
with UNKNOWN_VALUE. The register value that contains a kernel address is
then allowed to leak. Moreover, this fix allows unprivileged eBPF
programs to use functions with (legitimate) pointer arguments.

Not an issue currently since reg_type is only set for PTR_TO_PACKET or
PTR_TO_PACKET_END in XDP and TC programs that can only be loaded as
privileged. For now, the only unprivileged eBPF program allowed is for
socket filtering and all the types from its context are UNKNOWN_VALUE.
However, this fix is important for future unprivileged eBPF programs
which could use pointers in their context.

Signed-off-by: Mickaël Salaün <mic@digikod.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-27 03:51:34 -04:00
Linus Torvalds
4c04b4b534 Al Viro has been looking at the tracefs code, and has pointed out
some issues. This contains one fix by me and one by Al. I'm sure that
 he'll come up with more but for now I tested these patches and they
 don't appear to have any negative impact on tracing.
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Merge tag 'trace-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracefs fixes from Steven Rostedt:
 "Al Viro has been looking at the tracefs code, and has pointed out some
  issues.  This contains one fix by me and one by Al.  I'm sure that
  he'll come up with more but for now I tested these patches and they
  don't appear to have any negative impact on tracing"

* tag 'trace-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  fix memory leaks in tracing_buffers_splice_read()
  tracing: Move mutex to protect against resetting of seq data
2016-09-25 18:40:13 -07:00
Wei Yongjun
b8129a1f6a genirq: Make function __irq_do_set_handler() static
Fixes the following sparse warning:

kernel/irq/chip.c:786:1: warning:
 symbol '__irq_do_set_handler' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: http://lkml.kernel.org/r/1474817799-18676-1-git-send-email-weiyj.lk@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-25 16:46:52 -04:00
Al Viro
1ae2293dd6 fix memory leaks in tracing_buffers_splice_read()
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-25 13:30:13 -04:00
Steven Rostedt (Red Hat)
1245800c0f tracing: Move mutex to protect against resetting of seq data
The iter->seq can be reset outside the protection of the mutex. So can
reading of user data. Move the mutex up to the beginning of the function.

Fixes: d7350c3f45 ("tracing/core: make the read callbacks reentrants")
Cc: stable@vger.kernel.org # 2.6.30+
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-25 10:27:08 -04:00
Linus Torvalds
9c0e28a7be Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "Three fixlets for perf:

   - add a missing NULL pointer check in the intel BTS driver

   - make BTS an exclusive PMU because BTS can only handle one event at
     a time

   - ensure that exclusive events are limited to one PMU so that several
     exclusive events can be scheduled on different PMU instances"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Limit matching exclusive events to one PMU
  perf/x86/intel/bts: Make it an exclusive PMU
  perf/x86/intel/bts: Make sure debug store is valid
2016-09-24 12:44:28 -07:00
Linus Torvalds
4b8b0ff60f Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "Three fixes for irq core and irq chip drivers:

   - Do not set the irq type if type is NONE.  Fixes a boot regression
     on various SoCs

   - Use the proper cpu for setting up the GIC target list.  Discovered
     by the cpumask debugging code.

   - A rather large fix for the MIPS-GIC so per cpu local interrupts
     work again.  This was discovered late because the code falls back
     to slower timers which use normal device interrupts"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/mips-gic: Fix local interrupts
  irqchip/gicv3: Silence noisy DEBUG_PER_CPU_MAPS warning
  genirq: Skip chained interrupt trigger setup if type is IRQ_TYPE_NONE
2016-09-24 12:30:12 -07:00
Tejun Heo
9157056da8 cgroup: fix invalid controller enable rejections with cgroup namespace
On the v2 hierarchy, "cgroup.subtree_control" rejects controller
enables if the cgroup has processes in it.  The enforcement of this
logic assumes that the cgroup wouldn't have any css_sets associated
with it if there are no tasks in the cgroup, which is no longer true
since a79a908fd2 ("cgroup: introduce cgroup namespaces").

When a cgroup namespace is created, it pins the css_set of the
creating task to use it as the root css_set of the namespace.  This
extra reference stays as long as the namespace is around and makes
"cgroup.subtree_control" think that the namespace root cgroup is not
empty even when it is and thus reject controller enables.

Fix it by making cgroup_subtree_control() walk and test emptiness of
each css_set instead of testing whether the list_head is empty.

While at it, update the comment of cgroup_task_count() to indicate
that the returned value may be higher than the number of tasks, which
has always been true due to temporary references and doesn't break
anything.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Evgeny Vereshchagin <evvers@ya.ru>
Cc: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Cc: Aditya Kali <adityakali@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: stable@vger.kernel.org # v4.6+
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Link: https://github.com/systemd/systemd/pull/3589#issuecomment-249089541
2016-09-23 16:55:49 -04:00
Masami Hiramatsu
a0d0c6216a tracing: Call traceoff trigger after event is recorded
Call traceoff trigger after the event is recorded.
Since current traceoff trigger is called before recording
the event, we can not know what event stopped tracing.

Typical usecase of traceoff/traceon trigger is tracing
function calls and trace events between a pair of events.
For example, trace function calls between syscall entry/exit.
In that case, it is useful if we can see the return code
of the target syscall.

Link: http://lkml.kernel.org/r/147335074530.12462.4526186083406015005.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-23 09:47:59 -04:00
David S. Miller
d6989d4bbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-23 06:46:57 -04:00
Ingo Molnar
739f1bcd04 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-23 07:20:33 +02:00
Eric W. Biederman
7872559664 Merge branch 'nsfs-ioctls' into HEAD
From: Andrey Vagin <avagin@openvz.org>

Each namespace has an owning user namespace and now there is not way
to discover these relationships.

Pid and user namepaces are hierarchical. There is no way to discover
parent-child relationships too.

Why we may want to know relationships between namespaces?

One use would be visualization, in order to understand the running
system.  Another would be to answer the question: what capability does
process X have to perform operations on a resource governed by namespace
Y?

One more use-case (which usually called abnormal) is checkpoint/restart.
In CRIU we are going to dump and restore nested namespaces.

There [1] was a discussion about which interface to choose to determing
relationships between namespaces.

Eric suggested to add two ioctl-s [2]:
> Grumble, Grumble.  I think this may actually a case for creating ioctls
> for these two cases.  Now that random nsfs file descriptors are bind
> mountable the original reason for using proc files is not as pressing.
>
> One ioctl for the user namespace that owns a file descriptor.
> One ioctl for the parent namespace of a namespace file descriptor.

Here is an implementaions of these ioctl-s.

$ man man7/namespaces.7
...
Since  Linux  4.X,  the  following  ioctl(2)  calls are supported for
namespace file descriptors.  The correct syntax is:

      fd = ioctl(ns_fd, ioctl_type);

where ioctl_type is one of the following:

NS_GET_USERNS
      Returns a file descriptor that refers to an owning user names‐
      pace.

NS_GET_PARENT
      Returns  a  file descriptor that refers to a parent namespace.
      This ioctl(2) can be used for pid  and  user  namespaces.  For
      user namespaces, NS_GET_PARENT and NS_GET_USERNS have the same
      meaning.

In addition to generic ioctl(2) errors, the following  specific  ones
can occur:

EINVAL NS_GET_PARENT was called for a nonhierarchical namespace.

EPERM  The  requested  namespace  is outside of the current namespace
      scope.

[1] https://lkml.org/lkml/2016/7/6/158
[2] https://lkml.org/lkml/2016/7/9/101

Changes for v2:
* don't return ENOENT for init_user_ns and init_pid_ns. There is nothing
  outside of the init namespace, so we can return EPERM in this case too.
  > The fewer special cases the easier the code is to get
  > correct, and the easier it is to read. // Eric

Changes for v3:
* rename ns->get_owner() to ns->owner(). get_* usually means that it
  grabs a reference.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Cc: "W. Trevor King" <wking@tremily.us>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
2016-09-22 20:00:36 -05:00
Andrey Vagin
a7306ed8d9 nsfs: add ioctl to get a parent namespace
Pid and user namepaces are hierarchical. There is no way to discover
parent-child relationships.

In a future we will use this interface to dump and restore nested
namespaces.

Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-09-22 19:59:41 -05:00
Andrey Vagin
bcac25a58b kernel: add a helper to get an owning user namespace for a namespace
Return -EPERM if an owning user namespace is outside of a process
current user namespace.

v2: In a first version ns_get_owner returned ENOENT for init_user_ns.
    This special cases was removed from this version. There is nothing
    outside of init_user_ns, so we can return EPERM.
v3: rename ns->get_owner() to ns->owner(). get_* usually means that it
grabs a reference.

Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-09-22 19:59:39 -05:00
Rob Herring
ce836c2974 kvmconfig: add virtio-gpu to config fragment
virtio-gpu is used for VMs, so add it to the kvm config.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvmarm@lists.cs.columbia.edu
Cc: kvm@vger.kernel.org
[expanded "frag" to "fragment" in summary]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-09-23 01:08:13 +02:00
Rob Herring
bd6c92221d config: move x86 kvm_guest.config to a common location
kvm_guest.config is useful for KVM guests on other arches, and nothing
in it appears to be x86 specific, so just move the whole file. Kbuild
will find it in either location.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvmarm@lists.cs.columbia.edu
Cc: kvm@vger.kernel.org
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-09-23 01:08:12 +02:00
Eric W. Biederman
df75e7748b userns: When the per user per user namespace limit is reached return ENOSPC
The current error codes returned when a the per user per user
namespace limit are hit (EINVAL, EUSERS, and ENFILE) are wrong.  I
asked for advice on linux-api and it we made clear that those were
the wrong error code, but a correct effor code was not suggested.

The best general error code I have found for hitting a resource limit
is ENOSPC.  It is not perfect but as it is unambiguous it will serve
until someone comes up with a better error code.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-09-22 13:25:56 -05:00
Peter Zijlstra
d32cdbfb0b locking/lglock: Remove lglock implementation
It is now unused, remove it before someone else thinks its a good idea
to use this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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>
2016-09-22 15:25:56 +02:00
Oleg Nesterov
e625397041 stop_machine: Remove stop_cpus_lock and lg_double_lock/unlock()
stop_two_cpus() and stop_cpus() use stop_cpus_lock to avoid the deadlock,
we need to ensure that the stopper functions can't be queued "backwards"
from one another. This doesn't look nice; if we use lglock then we do not
really need stopper->lock, cpu_stop_queue_work() could use lg_local_lock()
under local_irq_save().

OTOH it would be even better to avoid lglock in stop_machine.c and remove
lg_double_lock(). This patch adds "bool stop_cpus_in_progress" set/cleared
by queue_stop_cpus_work(), and changes cpu_stop_queue_two_works() to busy
wait until it is cleared.

queue_stop_cpus_work() sets stop_cpus_in_progress = T lockless, but after
it queues a work on CPU1 it must be visible to stop_two_cpus(CPU1, CPU2)
which checks it under the same lock. And since stop_two_cpus() holds the
2nd lock too, queue_stop_cpus_work() can not clear stop_cpus_in_progress
if it is also going to queue a work on CPU2, it needs to take that 2nd
lock to do this.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151121181148.GA433@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 15:25:55 +02:00
Pan Xinhui
b193049375 locking/pv-qspinlock: Use cmpxchg_release() in __pv_queued_spin_unlock()
cmpxchg_release() is more lighweight than cmpxchg() on some archs(e.g.
PPC), moreover, in __pv_queued_spin_unlock() we only needs a RELEASE in
the fast path(pairing with *_try_lock() or *_lock()). And the slow path
has smp_store_release too. So it's safe to use cmpxchg_release here.

Suggested-by:  Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: virtualization@lists.linux-foundation.org
Cc: waiman.long@hpe.com
Link: http://lkml.kernel.org/r/1474277037-15200-2-git-send-email-xinhui.pan@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 15:25:51 +02:00
Ingo Molnar
7cf0f1426a Merge branch 'locking/urgent' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 15:21:48 +02:00
Peter Zijlstra
a18a579e5f sched/debug: Hide printk() by default
Dietmar accidentally added an unconditional sched domain printk. Hide
it behind the normal sched_debug flag.

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
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
Fixes: cd92bfd3b8 ("sched/core: Store maximum per-CPU capacity in root domain")
[ Fixed !SCHED_DEBUG build failure. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 15:20:25 +02:00
Srivatsa Vaddagiri
8bf46a39be sched/fair: Fix SCHED_HRTICK bug leading to late preemption of tasks
SCHED_HRTICK feature is useful to preempt SCHED_FAIR tasks on-the-dot
(just when they would have exceeded their ideal_runtime).

It makes use of a per-CPU hrtimer resource and hence arming that
hrtimer should be based on total SCHED_FAIR tasks a CPU has across its
various cfs_rqs, rather than being based on number of tasks in a
particular cfs_rq (as implemented currently).

As a result, with current code, its possible for a running task (which
is the sole task in its cfs_rq) to be preempted much after its
ideal_runtime has elapsed, resulting in increased latency for tasks in
other cfs_rq on same CPU.

Fix this by arming sched hrtimer based on total number of SCHED_FAIR
tasks a CPU has across its various cfs_rqs.

Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1474075731-11550-1-git-send-email-joonwoop@codeaurora.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 15:20:18 +02:00
Alexander Shishkin
3bf6215a1b perf/core: Limit matching exclusive events to one PMU
An "exclusive" PMU is the one that can only have one event scheduled in
at any given time. There may be more than one of such PMUs in a system,
though, like Intel PT and BTS. It should be allowed to have one event
for either of those inside the same context (there may be other constraints
that may prevent this, but those would be hardware-specific). However,
the exclusivity code is written so that only one event from any of the
"exclusive" PMUs is allowed in a context.

Fix this by making the exclusive event filter explicitly match two events'
PMUs.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/20160920154811.3255-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:56:09 +02:00
Peter Zijlstra
35a773a079 sched/core: Avoid _cond_resched() for PREEMPT=y
On fully preemptible kernels _cond_resched() is pointless, so avoid
emitting any code for it.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
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>
2016-09-22 14:53:46 +02:00
Peter Zijlstra
9af6528ee9 sched/core: Optimize __schedule()
Oleg noted that by making do_exit() use __schedule() for the TASK_DEAD
context switch, we can avoid the TASK_DEAD special case currently in
__schedule() because that avoids the extra preempt_disable() from
schedule().

In order to facilitate this, create a do_task_dead() helper which we
place in the scheduler code, such that it can access __schedule().

Also add some __noreturn annotations to the functions, there's no
coming back from do_exit().

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Cheng Chao <cs.os.kernel@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: chris@chris-wilson.co.uk
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/20160913163729.GB5012@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:53:45 +02:00
Cheng Chao
bf89a30472 stop_machine: Avoid a sleep and wakeup in stop_one_cpu()
In case @cpu == smp_proccessor_id(), we can avoid a sleep+wakeup
cycle by doing a preemption.

Callers such as sched_exec() can benefit from this change.

Signed-off-by: Cheng Chao <cs.os.kernel@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: chris@chris-wilson.co.uk
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/1473818510-6779-1-git-send-email-cs.os.kernel@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:53:45 +02:00
Cheng Chao
0b8473570c sched/core: Remove unnecessary initialization in sched_init()
init_idle() is called immediately after:

  current->sched_class = &fair_sched_class;

init_idle() sets:

  current->sched_class = &idle_sched_class;

First assignment is superfluous.

Signed-off-by: Cheng Chao <cs.os.kernel@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1473819536-7398-1-git-send-email-cs.os.kernel@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:53:44 +02:00
Ingo Molnar
50797851b4 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:49:40 +02:00
Peter Zijlstra
8db549491c smp: Allocate smp_call_on_cpu() workqueue on stack too
The SMP IPI struct descriptor is allocated on the stack except for the
workqueue and lockdep complains:

  INFO: trying to register non-static key.
  the code is fine but needs lockdep annotation.
  turning off the locking correctness validator.
  CPU: 0 PID: 110 Comm: kworker/0:1 Not tainted 4.8.0-rc5+ #14
  Hardware name: Dell Inc. Precision T3600/0PTTT9, BIOS A13 05/11/2014
  Workqueue: events smp_call_on_cpu_callback
  ...
  Call Trace:
    dump_stack
    register_lock_class
    ? __lock_acquire
    __lock_acquire
    ? __lock_acquire
    lock_acquire
    ? process_one_work
    process_one_work
    ? process_one_work
    worker_thread
    ? process_one_work
    ? process_one_work
    kthread
    ? kthread_create_on_node
    ret_from_fork

So allocate it on the stack too.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[ Test and write commit message. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160911084323.jhtnpb4b37t5tlno@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:49:10 +02:00
Con Kolivas
4fa5cd5245 sched/core: Do not use smp_processor_id() with preempt enabled in smpboot_thread_fn()
We should not be using smp_processor_id() with preempt enabled.

Bug identified and fix provided by Alfred Chen.

Reported-by: Alfred Chen <cchalpha@gmail.com>
Signed-off-by: Con Kolivas <kernel@kolivas.org>
Cc: Alfred Chen <cchalpha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/2042051.3vvUWIM0vs@hex
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 12:28:00 +02:00
Jakub Kicinski
6b17387307 bpf: recognize 64bit immediate loads as consts
When running as parser interpret BPF_LD | BPF_IMM | BPF_DW
instructions as loading CONST_IMM with the value stored
in imm.  The verifier will continue not recognizing those
due to concerns about search space/program complexity
increase.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-21 19:50:02 -04:00
Jakub Kicinski
13a27dfc66 bpf: enable non-core use of the verfier
Advanced JIT compilers and translators may want to use
eBPF verifier as a base for parsers or to perform custom
checks and validations.

Add ability for external users to invoke the verifier
and provide callbacks to be invoked for every intruction
checked.  For now only add most basic callback for
per-instruction pre-interpretation checks is added.  More
advanced users may also like to have per-instruction post
callback and state comparison callback.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-21 19:50:02 -04:00
Jakub Kicinski
58e2af8b3a bpf: expose internal verfier structures
Move verifier's internal structures to a header file and
prefix their names with bpf_ to avoid potential namespace
conflicts.  Those structures will soon be used by external
analyzers.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-21 19:50:02 -04:00
Jakub Kicinski
3df126f35f bpf: don't (ab)use instructions to store state
Storing state in reserved fields of instructions makes
it impossible to run verifier on programs already
marked as read-only. Allocate and use an array of
per-instruction state instead.

While touching the error path rename and move existing
jump target.

Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-21 19:50:02 -04:00
Daniel Borkmann
36bbef52c7 bpf: direct packet write and access for helpers for clsact progs
This work implements direct packet access for helpers and direct packet
write in a similar fashion as already available for XDP types via commits
4acf6c0b84 ("bpf: enable direct packet data write for xdp progs") and
6841de8b0d ("bpf: allow helpers access the packet directly"), and as a
complementary feature to the already available direct packet read for tc
(cls/act) programs.

For enabling this, we need to introduce two helpers, bpf_skb_pull_data()
and bpf_csum_update(). The first is generally needed for both, read and
write, because they would otherwise only be limited to the current linear
skb head. Usually, when the data_end test fails, programs just bail out,
or, in the direct read case, use bpf_skb_load_bytes() as an alternative
to overcome this limitation. If such data sits in non-linear parts, we
can just pull them in once with the new helper, retest and eventually
access them.

At the same time, this also makes sure the skb is uncloned, which is, of
course, a necessary condition for direct write. As this needs to be an
invariant for the write part only, the verifier detects writes and adds
a prologue that is calling bpf_skb_pull_data() to effectively unclone the
skb from the very beginning in case it is indeed cloned. The heuristic
makes use of a similar trick that was done in 233577a220 ("net: filter:
constify detection of pkt_type_offset"). This comes at zero cost for other
programs that do not use the direct write feature. Should a program use
this feature only sparsely and has read access for the most parts with,
for example, drop return codes, then such write action can be delegated
to a tail called program for mitigating this cost of potential uncloning
to a late point in time where it would have been paid similarly with the
bpf_skb_store_bytes() as well. Advantage of direct write is that the
writes are inlined whereas the helper cannot make any length assumptions
and thus needs to generate a call to memcpy() also for small sizes, as well
as cost of helper call itself with sanity checks are avoided. Plus, when
direct read is already used, we don't need to cache or perform rechecks
on the data boundaries (due to verifier invalidating previous checks for
helpers that change skb->data), so more complex programs using rewrites
can benefit from switching to direct read plus write.

For direct packet access to helpers, we save the otherwise needed copy into
a temp struct sitting on stack memory when use-case allows. Both facilities
are enabled via may_access_direct_pkt_data() in verifier. For now, we limit
this to map helpers and csum_diff, and can successively enable other helpers
where we find it makes sense. Helpers that definitely cannot be allowed for
this are those part of bpf_helper_changes_skb_data() since they can change
underlying data, and those that write into memory as this could happen for
packet typed args when still cloned. bpf_csum_update() helper accommodates
for the fact that we need to fixup checksum_complete when using direct write
instead of bpf_skb_store_bytes(), meaning the programs can use available
helpers like bpf_csum_diff(), and implement csum_add(), csum_sub(),
csum_block_add(), csum_block_sub() equivalents in eBPF together with the
new helper. A usage example will be provided for iproute2's examples/bpf/
directory.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-20 23:32:11 -04:00
Daniel Borkmann
b399cf64e3 bpf, verifier: enforce larger zero range for pkt on overloading stack buffs
Current contract for the following two helper argument types is:

  * ARG_CONST_STACK_SIZE: passed argument pair must be (ptr, >0).
  * ARG_CONST_STACK_SIZE_OR_ZERO: passed argument pair can be either
    (NULL, 0) or (ptr, >0).

With 6841de8b0d ("bpf: allow helpers access the packet directly"), we can
pass also raw packet data to helpers, so depending on the argument type
being PTR_TO_PACKET, we now either assert memory via check_packet_access()
or check_stack_boundary(). As a result, the tests in check_packet_access()
currently allow more than intended with regards to reg->imm.

Back in 969bf05eb3 ("bpf: direct packet access"), check_packet_access()
was fine to ignore size argument since in check_mem_access() size was
bpf_size_to_bytes() derived and prior to the call to check_packet_access()
guaranteed to be larger than zero.

However, for the above two argument types, it currently means, we can have
a <= 0 size and thus breaking current guarantees for helpers. Enforce a
check for size <= 0 and bail out if so.

check_stack_boundary() doesn't have such an issue since it already tests
for access_size <= 0 and bails out, resp. access_size == 0 in case of NULL
pointer passed when allowed.

Fixes: 6841de8b0d ("bpf: allow helpers access the packet directly")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-20 23:32:11 -04:00
Thomas Gleixner
464b5847e6 Merge branch 'irq/urgent' into irq/core
Merge urgent fixes so pending patches for 4.9 can be applied.
2016-09-20 23:20:32 +02:00
Ingo Molnar
b2c16e1efd Merge branch 'linus' into x86/asm, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-20 08:29:21 +02:00
Johannes Weiner
d979a39d72 cgroup: duplicate cgroup reference when cloning sockets
When a socket is cloned, the associated sock_cgroup_data is duplicated
but not its reference on the cgroup.  As a result, the cgroup reference
count will underflow when both sockets are destroyed later on.

Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Link: http://lkml.kernel.org/r/20160914194846.11153-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org>	[4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-19 15:36:17 -07:00
Sebastian Andrzej Siewior
30e92153b4 padata: Convert to hotplug state machine
Install the callbacks via the state machine. CPU-hotplug multinstance support
is used with the nocalls() version. Maybe parts of padata_alloc() could be
moved into the online callback so that we could invoke ->startup callback for
instance and drop get_online_cpus().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-crypto@vger.kernel.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160906170457.32393-14-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-19 21:44:30 +02:00
Marc Zyngier
1984e07591 genirq: Skip chained interrupt trigger setup if type is IRQ_TYPE_NONE
There is no point in trying to configure the trigger of a chained
interrupt if no trigger information has been configured. At best
this is ignored, and at the worse this confuses the underlying
irqchip (which is likely not to handle such a thing), and
unnecessarily alarms the user.

Only apply the configuration if type is not IRQ_TYPE_NONE.

Fixes: 1e12c4a939 ("genirq: Correctly configure the trigger on chained interrupts")
Reported-and-tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/CAMuHMdVW1eTn20=EtYcJ8hkVwohaSuH_yQXrY2MGBEvZ8fpFOg@mail.gmail.com
Link: http://lkml.kernel.org/r/1474274967-15984-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-19 11:31:36 +02:00
Wei Yongjun
8a15b81741 cpuset: fix non static symbol warning
Fixes the following sparse warning:

kernel/cpuset.c:2088:6: warning:
 symbol 'cpuset_fork' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-09-16 11:31:17 -04:00
Andy Lutomirski
ac496bf48d fork: Optimize task creation by caching two thread stacks per CPU if CONFIG_VMAP_STACK=y
vmalloc() is a bit slow, and pounding vmalloc()/vfree() will eventually
force a global TLB flush.

To reduce pressure on them, if CONFIG_VMAP_STACK=y, cache two thread
stacks per CPU.  This will let us quickly allocate a hopefully
cache-hot, TLB-hot stack under heavy forking workloads (shell script style).

On my silly pthread_create() benchmark, it saves about 2 µs per
pthread_create()+join() with CONFIG_VMAP_STACK=y.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/94811d8e3994b2e962f88866290017d498eb069c.1474003868.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-16 09:18:54 +02:00
Andy Lutomirski
68f24b08ee sched/core: Free the stack early if CONFIG_THREAD_INFO_IN_TASK
We currently keep every task's stack around until the task_struct
itself is freed.  This means that we keep the stack allocation alive
for longer than necessary and that, under load, we free stacks in
big batches whenever RCU drops the last task reference.  Neither of
these is good for reuse of cache-hot memory, and freeing in batches
prevents us from usefully caching small numbers of vmalloced stacks.

On architectures that have thread_info on the stack, we can't easily
change this, but on architectures that set THREAD_INFO_IN_TASK, we
can free it as soon as the task is dead.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/08ca06cde00ebed0046c5d26cbbf3fbb7ef5b812.1474003868.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-16 09:18:54 +02:00
Oleg Nesterov
23196f2e5f kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function
get_task_struct(tsk) no longer pins tsk->stack so all users of
to_live_kthread() should do try_get_task_stack/put_task_stack to protect
"struct kthread" which lives on kthread's stack.

TODO: Kill to_live_kthread(), perhaps we can even kill "struct kthread" too,
and rework kthread_stop(), it can use task_work_add() to sync with the exiting
kernel thread.

Message-Id: <20160629180357.GA7178@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/cb9b16bbc19d4aea4507ab0552e4644c1211d130.1474003868.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-16 09:18:53 +02:00
Ingo Molnar
2d8fbcd13e Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

 - Expedited grace-period changes, most notably avoiding having
   user threads drive expedited grace periods, using a workqueue
   instead.

 - Miscellaneous fixes, including a performance fix for lists
   that was sent with the lists modifications (second URL below).

 - CPU hotplug updates, most notably providing exact CPU-online
   tracking for RCU.  This will in turn allow removal of the
   checks supporting RCU's prior heuristic that was based on the
   assumption that CPUs would take no longer than one jiffy to
   come online.

 - Torture-test updates.

 - Documentation updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-16 09:08:43 +02:00
Thomas Gleixner
0a30d69195 Merge branch 'irq/for-block' into irq/core
Add the new irq spreading infrastructure.
2016-09-15 20:54:40 +02:00
Andy Lutomirski
c65eacbe29 sched/core: Allow putting thread_info into task_struct
If an arch opts in by setting CONFIG_THREAD_INFO_IN_TASK_STRUCT,
then thread_info is defined as a single 'u32 flags' and is the first
entry of task_struct.  thread_info::task is removed (it serves no
purpose if thread_info is embedded in task_struct), and
thread_info::cpu gets its own slot in task_struct.

This is heavily based on a patch written by Linus.

Originally-from: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a0898196f0476195ca02713691a5037a14f2aac5.1473801993.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-15 08:25:13 +02:00
Ingo Molnar
d4b80afbba Merge branch 'linus' into x86/asm, to pick up recent fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-15 08:24:53 +02:00
Thomas Gleixner
44082fd670 genirq/affinity: Remove old irq spread infrastructure
No more users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Link: http://lkml.kernel.org/r/1473862739-15032-5-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14 22:11:09 +02:00
Thomas Gleixner
e75eafb9b0 genirq/msi: Switch to new irq spreading infrastructure
Switch MSI over to the new spreading code. If a pci device contains a valid
pointer to a cpumask, then this mask is used for spreading otherwise the
online cpu mask is used. This allows a driver to restrict the spread to a
subset of CPUs, e.g. cpus on a particular node.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Link: http://lkml.kernel.org/r/1473862739-15032-4-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14 22:11:09 +02:00
Thomas Gleixner
34c3d9819f genirq/affinity: Provide smarter irq spreading infrastructure
The current irq spreading infrastructure is just looking at a cpumask and
tries to spread the interrupts over the mask. Thats suboptimal as it does
not take numa nodes into account.

Change the logic so the interrupts are spread across numa nodes and inside
the nodes. If there are more cpus than vectors per node, then we set the
affinity to several cpus. If HT siblings are available we take that into
account and try to set all siblings to a single vector.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Link: http://lkml.kernel.org/r/1473862739-15032-3-git-send-email-hch@lst.de
2016-09-14 22:11:08 +02:00
Thomas Gleixner
28f4b04143 genirq/msi: Add cpumask allocation to alloc_msi_entry
For irq spreading want to store affinity masks in the msi_entry. Add the
infrastructure for it.

We allocate an array of cpumasks with an array size of the number of used
vectors in the entry, so we can hand in the information per linux interrupt
later.

As we hand in the number of used vectors, we assign them right
away. Convert all the call sites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/1473862739-15032-2-git-send-email-hch@lst.de
2016-09-14 22:11:08 +02:00
Paul E. McKenney
d74b62bc32 Merge branches 'doc.2016.08.22c', 'exp.2016.08.22c', 'fixes.2016.09.14a', 'hotplug.2016.08.22c' and 'torture.2016.08.22c' into HEAD
doc.2016.08.22c: Documentation updates
exp.2016.08.22c: Expedited grace-period updates
fixes.2016.09.14a: Miscellaneous fixes
hotplug.2016.08.22c: CPU-hotplug changes
torture.2016.08.22c: Torture-test changes
2016-09-14 12:58:49 -07:00
Dmitry Safonov
6846351052 x86/signal: Add SA_{X32,IA32}_ABI sa_flags
Introduce new flags that defines which ABI to use on creating sigframe.
Those flags kernel will set according to sigaction syscall ABI,
which set handler for the signal being delivered.

So that will drop the dependency on TIF_IA32/TIF_X32 flags on signal deliver.
Those flags will be used only under CONFIG_COMPAT.

Similar way ARM uses sa_flags to differ in which mode deliver signal
for 26-bit applications (look at SA_THIRYTWO).

Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: 0x7f454c46@gmail.com
Cc: oleg@redhat.com
Cc: linux-mm@kvack.org
Cc: gorcunov@openvz.org
Cc: xemul@virtuozzo.com
Link: http://lkml.kernel.org/r/20160905133308.28234-7-dsafonov@virtuozzo.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14 21:28:11 +02:00
Thomas Gleixner
16217dc79d First drop of irqchip updates for 4.9
- ACPI IORT core code
 - IORT support for the GICv3 ITS
 - A few of GIC cleanups
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Merge tag 'irqchip-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Merge the first drop of irqchip updates for 4.9 from Marc Zyngier:

- ACPI IORT core code
- IORT support for the GICv3 ITS
- A few of GIC cleanups
2016-09-14 20:53:26 +02:00
Craig Gallek
ecb3f394c5 genirq: Expose interrupt information through sysfs
Information about interrupts is exposed via /proc/interrupts, but the
format of that file has changed over kernel versions and differs across
architectures. It also has varying column numbers depending on hardware.

That all makes it hard for tools to parse.

To solve this, expose the information through sysfs so each irq attribute
is in a separate file in a consistent, machine parsable way.

This feature is only available when both CONFIG_SPARSE_IRQ and
CONFIG_SYSFS are enabled.

Examples:
  /sys/kernel/irq/18/actions:	i801_smbus,ehci_hcd:usb1,uhci_hcd:usb7
  /sys/kernel/irq/18/chip_name:	IR-IO-APIC
  /sys/kernel/irq/18/hwirq:		18
  /sys/kernel/irq/18/name:		fasteoi
  /sys/kernel/irq/18/per_cpu_count:	0,0
  /sys/kernel/irq/18/type:		level

  /sys/kernel/irq/25/actions:	ahci0
  /sys/kernel/irq/25/chip_name:	IR-PCI-MSI
  /sys/kernel/irq/25/hwirq:		512000
  /sys/kernel/irq/25/name:		edge
  /sys/kernel/irq/25/per_cpu_count:	29036,0
  /sys/kernel/irq/25/type:		edge

[ tglx: Moved kobject_del() under sparse_irq_lock, massaged code comments
  	and changelog ]

Signed-off-by: Craig Gallek <kraig@google.com>
Cc: David Decotigny <decot@google.com>
Link: http://lkml.kernel.org/r/1473783291-122873-1-git-send-email-kraigatgoog@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14 15:28:15 +02:00
Rafael J. Wysocki
21ca6d2c52 cpufreq: schedutil: Add iowait boosting
Modify the schedutil cpufreq governor to boost the CPU
frequency if the SCHED_CPUFREQ_IOWAIT flag is passed to
it via cpufreq_update_util().

If that happens, the frequency is set to the maximum during
the first update after receiving the SCHED_CPUFREQ_IOWAIT flag
and then the boost is reduced by half during each following update.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Looks-good-to: Steve Muckle <smuckle@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-09-13 23:36:01 +02:00
Rafael J. Wysocki
8c34ab1910 cpufreq / sched: SCHED_CPUFREQ_IOWAIT flag to indicate iowait condition
Testing indicates that it is possible to improve performace
significantly without increasing energy consumption too much by
teaching cpufreq governors to bump up the CPU performance level if
the in_iowait flag is set for the task in enqueue_task_fair().

For this purpose, define a new cpufreq_update_util() flag
SCHED_CPUFREQ_IOWAIT and modify enqueue_task_fair() to pass that
flag to cpufreq_update_util() in the in_iowait case.  That generally
requires cpufreq_update_util() to be called directly from there,
because update_load_avg() may not be invoked in that case.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Looks-good-to: Steve Muckle <smuckle@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-09-13 23:36:01 +02:00
Linus Torvalds
fda67514e4 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
 "A try_to_wake_up() memory ordering race fix causing a busy-loop in
  ttwu()"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Fix a race between try_to_wake_up() and a woken up task
2016-09-13 12:49:40 -07:00
Linus Torvalds
ee319d5834 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This contains:

   - a set of fixes found by directed-random perf fuzzing efforts by
     Vince Weaver, Alexander Shishkin and Peter Zijlstra

   - a cqm driver crash fix

   - an AMD uncore driver use after free fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Fix PEBSv3 record drain
  perf/x86/intel/bts: Kill a silly warning
  perf/x86/intel/bts: Fix BTS PMI detection
  perf/x86/intel/bts: Fix confused ordering of PMU callbacks
  perf/core: Fix aux_mmap_count vs aux_refcount order
  perf/core: Fix a race between mmap_close() and set_output() of AUX events
  perf/x86/amd/uncore: Prevent use after free
  perf/x86/intel/cqm: Check cqm/mbm enabled state in event init
  perf/core: Remove WARN from perf_event_read()
2016-09-13 12:47:29 -07:00
Wanpeng Li
57ccdf449f tick/nohz: Prevent stopping the tick on an offline CPU
can_stop_full_tick() has no check for offline cpus. So it allows to stop
the tick on an offline cpu from the interrupt return path, which is wrong
and subsequently makes irq_work_needs_cpu() warn about being called for an
offline cpu.

Commit f7ea0fd639 ("tick: Don't invoke tick_nohz_stop_sched_tick() if
the cpu is offline") added prevention for can_stop_idle_tick(), but forgot
to do the same in can_stop_full_tick(). Add it.

[ tglx: Massaged changelog ]

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1473245473-4463-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-13 17:53:52 +02:00
Joonwoo Park
28b89b9e6f cpuset: handle race between CPU hotplug and cpuset_hotplug_work
A discrepancy between cpu_online_mask and cpuset's effective_cpus
mask is inevitable during hotplug since cpuset defers updating of
effective_cpus mask using a workqueue, during which time nothing
prevents the system from more hotplug operations.  For that reason
guarantee_online_cpus() walks up the cpuset hierarchy until it finds
an intersection under the assumption that top cpuset's effective_cpus
mask intersects with cpu_online_mask even with such a race occurring.

However a sequence of CPU hotplugs can open a time window, during which
none of the effective CPUs in the top cpuset intersect with
cpu_online_mask.

For example when there are 4 possible CPUs 0-3 and only CPU0 is online:

  ========================  ===========================
   cpu_online_mask           top_cpuset.effective_cpus
  ========================  ===========================
   echo 1 > cpu2/online.
   CPU hotplug notifier woke up hotplug work but not yet scheduled.
      [0,2]                     [0]

   echo 0 > cpu0/online.
   The workqueue is still runnable.
      [2]                       [0]
  ========================  ===========================

  Now there is no intersection between cpu_online_mask and
  top_cpuset.effective_cpus.  Thus invoking sys_sched_setaffinity() at
  this moment can cause following:

   Unable to handle kernel NULL pointer dereference at virtual address 000000d0
   ------------[ cut here ]------------
   Kernel BUG at ffffffc0001389b0 [verbose debug info unavailable]
   Internal error: Oops - BUG: 96000005 [#1] PREEMPT SMP
   Modules linked in:
   CPU: 2 PID: 1420 Comm: taskset Tainted: G        W       4.4.8+ #98
   task: ffffffc06a5c4880 ti: ffffffc06e124000 task.ti: ffffffc06e124000
   PC is at guarantee_online_cpus+0x2c/0x58
   LR is at cpuset_cpus_allowed+0x4c/0x6c
   <snip>
   Process taskset (pid: 1420, stack limit = 0xffffffc06e124020)
   Call trace:
   [<ffffffc0001389b0>] guarantee_online_cpus+0x2c/0x58
   [<ffffffc00013b208>] cpuset_cpus_allowed+0x4c/0x6c
   [<ffffffc0000d61f0>] sched_setaffinity+0xc0/0x1ac
   [<ffffffc0000d6374>] SyS_sched_setaffinity+0x98/0xac
   [<ffffffc000085cb0>] el0_svc_naked+0x24/0x28

The top cpuset's effective_cpus are guaranteed to be identical to
cpu_online_mask eventually.  Hence fall back to cpu_online_mask when
there is no intersection between top cpuset's effective_cpus and
cpu_online_mask.

Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: cgroups@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.17+
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-09-13 11:26:27 -04:00
Anisse Astier
1ad1410f63 PM / Hibernate: allow hibernation with PAGE_POISONING_ZERO
PAGE_POISONING_ZERO disables zeroing new pages on alloc, they are
poisoned (zeroed) as they become available.
In the hibernate use case, free pages will appear in the system without
being cleared, left there by the loading kernel.

This patch will make sure free pages are cleared on resume when
PAGE_POISONING_ZERO is enabled. We free the pages just after resume
because we can't do it later: going through any device resume code might
allocate some memory and invalidate the free pages bitmap.

Thus we don't need to disable hibernation when PAGE_POISONING_ZERO is
enabled.

Signed-off-by: Anisse Astier <anisse@astier.eu>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13 02:35:27 +02:00
Sudeep Holla
fa7fd6fa38 PM / sleep: enable suspend-to-idle even without registered suspend_ops
Suspend-to-idle (aka the "freeze" sleep state) is a system sleep state
in which all of the processors enter deepest possible idle state and
wait for interrupts right after suspending all the devices.

There is no hard requirement for a platform to support and register
platform specific suspend_ops to enter suspend-to-idle/freeze state.
Only deeper system sleep states like PM_SUSPEND_STANDBY and
PM_SUSPEND_MEM rely on such low level support/implementation.

suspend-to-idle can be entered as along as all the devices can be
suspended. This patch enables the support for suspend-to-idle even on
systems that don't have any low level support for deeper system sleep
states and/or don't register any platform specific suspend_ops.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13 02:17:19 +02:00
Chen Yu
5b3f249c94 PM / sleep: Increase default DPM watchdog timeout to 120
Recently we have a new report that, the harddisk can not
resume on time due to firmware issues, and got a kernel
panic because of DPM watchdog timeout. So adjust the
default timeout from 60 to 120 to survive on this platform,
and make DPM_WATCHDOG depending on EXPERT.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=117971
Suggested-by: Pavel Machek <pavel@ucw.cz>
Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Reported-by: Higuita <higuita@gmx.net>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13 02:15:58 +02:00
David S. Miller
b20b378d49 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/mediatek/mtk_eth_soc.c
	drivers/net/ethernet/qlogic/qed/qed_dcbx.c
	drivers/net/phy/Kconfig

All conflicts were cases of overlapping commits.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-12 15:52:44 -07:00
Steven Rostedt (Red Hat)
f971cc9aab tracing: Have max_latency be defined for HWLAT_TRACER as well
The hwlat tracer uses tr->max_latency, and if it's the only tracer enabled
that uses it, the build will fail. Add max_latency and its file when the
hwlat tracer is enabled.

Link: http://lkml.kernel.org/r/d6c3b7eb-ba95-1ffa-0453-464e1e24262a@infradead.org

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-12 09:59:46 -04:00
Linus Torvalds
98ac9a608d Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
 "nvdimm fixes for v4.8, two of them are tagged for -stable:

   - Fix devm_memremap_pages() to use track_pfn_insert().  Otherwise,
     DAX pmd mappings end up with an uncached pgprot, and unusable
     performance for the device-dax interface.  The device-dax interface
     appeared in 4.7 so this is tagged for -stable.

   - Fix a couple VM_BUG_ON() checks in the show_smaps() path to
     understand DAX pmd entries.  This fix is tagged for -stable.

   - Fix a mis-merge of the nfit machine-check handler to flip the
     polarity of an if() to match the final version of the patch that
     Vishal sent for 4.8-rc1.  Without this the nfit machine check
     handler never detects / inserts new 'badblocks' entries which
     applications use to identify lost portions of files.

   - For test purposes, fix the nvdimm_clear_poison() path to operate on
     legacy / simulated nvdimm memory ranges.  Without this fix a test
     can set badblocks, but never clear them on these ranges.

   - Fix the range checking done by dax_dev_pmd_fault().  This is not
     tagged for -stable since this problem is mitigated by specifying
     aligned resources at device-dax setup time.

  These patches have appeared in a next release over the past week.  The
  recent rebase you can see in the timestamps was to drop an invalid fix
  as identified by the updated device-dax unit tests [1].  The -mm
  touches have an ack from Andrew"

[1]: "[ndctl PATCH 0/3] device-dax test for recent kernel bugs"
   https://lists.01.org/pipermail/linux-nvdimm/2016-September/006855.html

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm: allow legacy (e820) pmem region to clear bad blocks
  nfit, mce: Fix SPA matching logic in MCE handler
  mm: fix cache mode of dax pmd mappings
  mm: fix show_smap() for zone_device-pmd ranges
  dax: fix mapping size check
2016-09-10 09:58:52 -07:00
Ingo Molnar
5006921837 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-10 11:17:54 +02:00
Peter Zijlstra
de58af878d Revert "sched/fair: Make update_min_vruntime() more readable"
There's a bug in this commit:

   97a7142f15 ("sched/fair: Make update_min_vruntime() more readable")

... when !rb_leftmost && curr we fail to advance min_vruntime.

So revert it.

Reported-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-10 11:17:40 +02:00
Alexander Shishkin
b79ccadd6b perf/core: Fix aux_mmap_count vs aux_refcount order
The order of accesses to ring buffer's aux_mmap_count and aux_refcount
has to be preserved across the users, namely perf_mmap_close() and
perf_aux_output_begin(), otherwise the inversion can result in the latter
holding the last reference to the aux buffer and subsequently free'ing
it in atomic context, triggering a warning.

> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 257 at kernel/events/ring_buffer.c:541 __rb_free_aux+0x11a/0x130
> CPU: 0 PID: 257 Comm: stopbug Not tainted 4.8.0-rc1+ #2596
> Call Trace:
>  [<ffffffff810f3e0b>] __warn+0xcb/0xf0
>  [<ffffffff810f3f3d>] warn_slowpath_null+0x1d/0x20
>  [<ffffffff8121182a>] __rb_free_aux+0x11a/0x130
>  [<ffffffff812127a8>] rb_free_aux+0x18/0x20
>  [<ffffffff81212913>] perf_aux_output_begin+0x163/0x1e0
>  [<ffffffff8100c33a>] bts_event_start+0x3a/0xd0
>  [<ffffffff8100c42d>] bts_event_add+0x5d/0x80
>  [<ffffffff81203646>] event_sched_in.isra.104+0xf6/0x2f0
>  [<ffffffff8120652e>] group_sched_in+0x6e/0x190
>  [<ffffffff8120694e>] ctx_sched_in+0x2fe/0x5f0
>  [<ffffffff81206ca0>] perf_event_sched_in+0x60/0x80
>  [<ffffffff81206d1b>] ctx_resched+0x5b/0x90
>  [<ffffffff81207281>] __perf_event_enable+0x1e1/0x240
>  [<ffffffff81200639>] event_function+0xa9/0x180
>  [<ffffffff81202000>] ? perf_cgroup_attach+0x70/0x70
>  [<ffffffff8120203f>] remote_function+0x3f/0x50
>  [<ffffffff811971f3>] flush_smp_call_function_queue+0x83/0x150
>  [<ffffffff81197bd3>] generic_smp_call_function_single_interrupt+0x13/0x60
>  [<ffffffff810a6477>] smp_call_function_single_interrupt+0x27/0x40
>  [<ffffffff81a26ea9>] call_function_single_interrupt+0x89/0x90
>  [<ffffffff81120056>] finish_task_switch+0xa6/0x210
>  [<ffffffff81120017>] ? finish_task_switch+0x67/0x210
>  [<ffffffff81a1e83d>] __schedule+0x3dd/0xb50
>  [<ffffffff81a1efe5>] schedule+0x35/0x80
>  [<ffffffff81128031>] sys_sched_yield+0x61/0x70
>  [<ffffffff81a25be5>] entry_SYSCALL_64_fastpath+0x18/0xa8
> ---[ end trace 6235f556f5ea83a9 ]---

This patch puts the checks in perf_aux_output_begin() in the same order
as that of perf_mmap_close().

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/20160906132353.19887-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-10 11:15:36 +02:00
Alexander Shishkin
767ae08678 perf/core: Fix a race between mmap_close() and set_output() of AUX events
In the mmap_close() path we need to stop all the AUX events that are
writing data to the AUX area that we are unmapping, before we can
safely free the pages. To determine if an event needs to be stopped,
we're comparing its ->rb against the one that's getting unmapped.
However, a SET_OUTPUT ioctl may turn up inside an AUX transaction
and swizzle event::rb to some other ring buffer, but the transaction
will keep writing data to the old ring buffer until the event gets
scheduled out. At this point, mmap_close() will skip over such an
event and will proceed to free the AUX area, while it's still being
used by this event, which will set off a warning in the mmap_close()
path and cause a memory corruption.

To avoid this, always stop an AUX event before its ->rb is updated;
this will release the (potentially) last reference on the AUX area
of the buffer. If the event gets restarted, its new ring buffer will
be used. If another SET_OUTPUT comes and switches it back to the
old ring buffer that's getting unmapped, it's also fine: this
ring buffer's aux_mmap_count will be zero and AUX transactions won't
start any more.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/20160906132353.19887-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-10 11:15:36 +02:00
Daniel Borkmann
f3694e0012 bpf: add BPF_CALL_x macros for declaring helpers
This work adds BPF_CALL_<n>() macros and converts all the eBPF helper functions
to use them, in a similar fashion like we do with SYSCALL_DEFINE<n>() macros
that are used today. Motivation for this is to hide all the register handling
and all necessary casts from the user, so that it is done automatically in the
background when adding a BPF_CALL_<n>() call.

This makes current helpers easier to review, eases to write future helpers,
avoids getting the casting mess wrong, and allows for extending all helpers at
once (f.e. build time checks, etc). It also helps detecting more easily in
code reviews that unused registers are not instrumented in the code by accident,
breaking compatibility with existing programs.

BPF_CALL_<n>() internals are quite similar to SYSCALL_DEFINE<n>() ones with some
fundamental differences, for example, for generating the actual helper function
that carries all u64 regs, we need to fill unused regs, so that we always end up
with 5 u64 regs as an argument.

I reviewed several 0-5 generated BPF_CALL_<n>() variants of the .i results and
they look all as expected. No sparse issue spotted. We let this also sit for a
few days with Fengguang's kbuild test robot, and there were no issues seen. On
s390, it barked on the "uses dynamic stack allocation" notice, which is an old
one from bpf_perf_event_output{,_tp}() reappearing here due to the conversion
to the call wrapper, just telling that the perf raw record/frag sits on stack
(gcc with s390's -mwarn-dynamicstack), but that's all. Did various runtime tests
and they were fine as well. All eBPF helpers are now converted to use these
macros, getting rid of a good chunk of all the raw castings.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 19:36:04 -07:00
Daniel Borkmann
f035a51536 bpf: add BPF_SIZEOF and BPF_FIELD_SIZEOF macros
Add BPF_SIZEOF() and BPF_FIELD_SIZEOF() macros to improve the code a bit
which otherwise often result in overly long bytes_to_bpf_size(sizeof())
and bytes_to_bpf_size(FIELD_SIZEOF()) lines. So place them into a macro
helper instead. Moreover, we currently have a BUILD_BUG_ON(BPF_FIELD_SIZEOF())
check in convert_bpf_extensions(), but we should rather make that generic
as well and add a BUILD_BUG_ON() test in all BPF_SIZEOF()/BPF_FIELD_SIZEOF()
users to detect any rewriter size issues at compile time. Note, there are
currently none, but we want to assert that it stays this way.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 19:36:04 -07:00
Daniel Borkmann
6088b5823b bpf: minor cleanups in helpers
Some minor misc cleanups, f.e. use sizeof(__u32) instead of hardcoding
and in __bpf_skb_max_len(), I missed that we always have skb->dev valid
anyway, so we can drop the unneeded test for dev; also few more other
misc bits addressed here.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 19:36:03 -07:00
Dan Williams
9049771f7d mm: fix cache mode of dax pmd mappings
track_pfn_insert() in vmf_insert_pfn_pmd() is marking dax mappings as
uncacheable rendering them impractical for application usage.  DAX-pte
mappings are cached and the goal of establishing DAX-pmd mappings is to
attain more performance, not dramatically less (3 orders of magnitude).

track_pfn_insert() relies on a previous call to reserve_memtype() to
establish the expected page_cache_mode for the range.  While memremap()
arranges for reserve_memtype() to be called, devm_memremap_pages() does
not.  So, teach track_pfn_insert() and untrack_pfn() how to handle
tracking without a vma, and arrange for devm_memremap_pages() to
establish the write-back-cache reservation in the memtype tree.

Cc: <stable@vger.kernel.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Reported-by: Kai Zhang <kai.ka.zhang@oracle.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-09-09 17:34:46 -07:00
Daniel Borkmann
2d2be8cab2 bpf: fix range propagation on direct packet access
LLVM can generate code that tests for direct packet access via
skb->data/data_end in a way that currently gets rejected by the
verifier, example:

  [...]
   7: (61) r3 = *(u32 *)(r6 +80)
   8: (61) r9 = *(u32 *)(r6 +76)
   9: (bf) r2 = r9
  10: (07) r2 += 54
  11: (3d) if r3 >= r2 goto pc+12
   R1=inv R2=pkt(id=0,off=54,r=0) R3=pkt_end R4=inv R6=ctx
   R9=pkt(id=0,off=0,r=0) R10=fp
  12: (18) r4 = 0xffffff7a
  14: (05) goto pc+430
  [...]

  from 11 to 24: R1=inv R2=pkt(id=0,off=54,r=0) R3=pkt_end R4=inv
                 R6=ctx R9=pkt(id=0,off=0,r=0) R10=fp
  24: (7b) *(u64 *)(r10 -40) = r1
  25: (b7) r1 = 0
  26: (63) *(u32 *)(r6 +56) = r1
  27: (b7) r2 = 40
  28: (71) r8 = *(u8 *)(r9 +20)
  invalid access to packet, off=20 size=1, R9(id=0,off=0,r=0)

The reason why this gets rejected despite a proper test is that we
currently call find_good_pkt_pointers() only in case where we detect
tests like rX > pkt_end, where rX is of type pkt(id=Y,off=Z,r=0) and
derived, for example, from a register of type pkt(id=Y,off=0,r=0)
pointing to skb->data. find_good_pkt_pointers() then fills the range
in the current branch to pkt(id=Y,off=0,r=Z) on success.

For above case, we need to extend that to recognize pkt_end >= rX
pattern and mark the other branch that is taken on success with the
appropriate pkt(id=Y,off=0,r=Z) type via find_good_pkt_pointers().
Since eBPF operates on BPF_JGT (>) and BPF_JGE (>=), these are the
only two practical options to test for from what LLVM could have
generated, since there's no such thing as BPF_JLT (<) or BPF_JLE (<=)
that we would need to take into account as well.

After the fix:

  [...]
   7: (61) r3 = *(u32 *)(r6 +80)
   8: (61) r9 = *(u32 *)(r6 +76)
   9: (bf) r2 = r9
  10: (07) r2 += 54
  11: (3d) if r3 >= r2 goto pc+12
   R1=inv R2=pkt(id=0,off=54,r=0) R3=pkt_end R4=inv R6=ctx
   R9=pkt(id=0,off=0,r=0) R10=fp
  12: (18) r4 = 0xffffff7a
  14: (05) goto pc+430
  [...]

  from 11 to 24: R1=inv R2=pkt(id=0,off=54,r=54) R3=pkt_end R4=inv
                 R6=ctx R9=pkt(id=0,off=0,r=54) R10=fp
  24: (7b) *(u64 *)(r10 -40) = r1
  25: (b7) r1 = 0
  26: (63) *(u32 *)(r6 +56) = r1
  27: (b7) r2 = 40
  28: (71) r8 = *(u8 *)(r9 +20)
  29: (bf) r1 = r8
  30: (25) if r8 > 0x3c goto pc+47
   R1=inv56 R2=imm40 R3=pkt_end R4=inv R6=ctx R8=inv56
   R9=pkt(id=0,off=0,r=54) R10=fp
  31: (b7) r1 = 1
  [...]

Verifier test cases are also added in this work, one that demonstrates
the mentioned example here and one that tries a bad packet access for
the current/fall-through branch (the one with types pkt(id=X,off=Y,r=0),
pkt(id=X,off=0,r=0)), then a case with good and bad accesses, and two
with both test variants (>, >=).

Fixes: 969bf05eb3 ("bpf: direct packet access")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 17:28:37 -07:00
Ingo Molnar
950d8381d9 Merge branch 'linus' into timers/core, to refresh the branch
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-08 14:05:16 +02:00
Arnd Bergmann
f1e4ba5b6a perf, bpf: fix conditional call to bpf_overflow_handler
The newly added bpf_overflow_handler function is only built of both
CONFIG_EVENT_TRACING and CONFIG_BPF_SYSCALL are enabled, but the caller
only checks the latter:

kernel/events/core.c: In function 'perf_event_alloc':
kernel/events/core.c:9106:27: error: 'bpf_overflow_handler' undeclared (first use in this function)

This changes the caller so we also skip this call if CONFIG_EVENT_TRACING
is disabled entirely.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: aa6a5f3cb2 ("perf, bpf: add perf events core support for BPF_PROG_TYPE_PERF_EVENT programs")
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 16:34:14 -07:00
Sebastian Andrzej Siewior
c4544dbc7a kernel/softirq: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160818125731.27256-7-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 18:30:22 +02:00
Sebastian Andrzej Siewior
6731d4f123 slab: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: linux-mm@kvack.org
Cc: rt@linutronix.de
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Link: http://lkml.kernel.org/r/20160823125319.abeapfjapf2kfezp@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 18:30:20 +02:00
Richard Weinberger
e6d4989a9a relayfs: Convert to hotplug state machine
Install the callbacks via the state machine. They are installed at run time but
relay_prepare_cpu() does not need to be invoked by the boot CPU because
relay_open() was not yet invoked and there are no pools that need to be created.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20160818125731.27256-3-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 18:30:20 +02:00
Akash Goel
017c59c042 relay: Use per CPU constructs for the relay channel buffer pointers
relay essentially needs to maintain a per CPU array of channel buffer
pointers but it manually creates that array.  Instead its better to use
the per CPU constructs, provided by the kernel, to allocate & access the
array of pointer to channel buffers.

Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://lkml.kernel.org/r/1470909140-25919-1-git-send-email-akash.goel@intel.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 18:30:19 +02:00
Thomas Gleixner
ee1e714b94 cpu/hotplug: Remove CPU_STARTING and CPU_DYING notifier
All users are converted to state machine, remove CPU_STARTING and the
corresponding CPU_DYING.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160818125731.27256-2-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 18:30:19 +02:00
Thomas Gleixner
677f664653 cpu/hotplug: Make state names consistent
We should have all names in the scheme "[subsys/]facility:state]". Fix the
core to comply.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 16:20:28 +02:00
Alexander Kuleshov
00b992deaa genirq: No need to mask non trigger mode flags before __irq_set_trigger()
Some callers of __irq_set_trigger() masks all flags except trigger mode
flags. This is unnecessary, ase __irq_set_trigger() already does this
before usage of flags.

[ tglx: Moved the flag mask and adjusted comment. Removed the hunk in
  	enable_percpu_irq() as it is required there ]

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Link: http://lkml.kernel.org/r/20160719095408.13778-1-kuleshovmail@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-06 12:14:12 +02:00
Thomas Gleixner
e8b61b3f2c futex: Add some more function commentry
Add some more comments and reformat existing ones to kernel doc style.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Link: http://lkml.kernel.org/r/1464770609-30168-1-git-send-email-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-05 17:20:18 +02:00
Punit Agrawal
545d5d657b genirq: Update stale comment for __irq_domain_add
Commit 1bf4ddc46c ("irqdomain: Introduce irq_domain_create_{linear,
tree}") introduced the use of fwnode_handle to identify the interrupt
controller when calling __irq_domain_add but missed updating the kernel
doc parameters for the function.

Update this comment. While we are touching this code, also consolidate
the declaration and assignment of of_node.

Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Marc Zygnier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1464699409-23113-1-git-send-email-punit.agrawal@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-05 17:11:10 +02:00
Thomas Gleixner
3c1627e999 cpu/hotplug: Replace anon union
Some compilers are unhappy with the anon union in the state array. Replace
it with a named union.

While at it align the state array initializers proper and add the missing
name tags.

Fixes: cf392d10b6 "cpu/hotplug: Add multi instance support"
Reported-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Fenguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
2016-09-05 15:32:58 +02:00
Tejun Heo
c86d06ba28 PM / QoS: avoid calling cancel_delayed_work_sync() during early boot
of_clk_init() ends up calling into pm_qos_update_request() very early
during boot where irq is expected to stay disabled.
pm_qos_update_request() uses cancel_delayed_work_sync() which
correctly assumes that irq is enabled on invocation and
unconditionally disables and re-enables it.

Gate cancel_delayed_work_sync() invocation with kevented_up() to avoid
enabling irq unexpectedly during early boot.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Qiao Zhou <qiaozhou@asrmicro.com>
Link: http://lkml.kernel.org/r/d2501c4c-8e7b-bea3-1b01-000b36b5dfe9@asrmicro.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-05 15:07:53 +02:00
Juergen Gross
df8ce9d78a smp: Add function to execute a function synchronously on a CPU
On some hardware models (e.g. Dell Studio 1555 laptop) some hardware
related functions (e.g. SMIs) are to be executed on physical CPU 0
only. Instead of open coding such a functionality multiple times in
the kernel add a service function for this purpose. This will enable
the possibility to take special measures in virtualized environments
like Xen, too.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Douglas_Warzecha@dell.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: boris.ostrovsky@oracle.com
Cc: chrisw@sous-sol.org
Cc: david.vrabel@citrix.com
Cc: hpa@zytor.com
Cc: jdelvare@suse.com
Cc: jeremy@goop.org
Cc: linux@roeck-us.net
Cc: pali.rohar@gmail.com
Cc: rusty@rustcorp.com.au
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1472453327-19050-4-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 13:52:39 +02:00
Juergen Gross
47ae4b05d0 virt, sched: Add generic vCPU pinning support
Add generic virtualization support for pinning the current vCPU to a
specified physical CPU. As this operation isn't performance critical
(a very limited set of operations like BIOS calls and SMIs is expected
to need this) just add a hypervisor specific indirection.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Douglas_Warzecha@dell.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: boris.ostrovsky@oracle.com
Cc: chrisw@sous-sol.org
Cc: david.vrabel@citrix.com
Cc: hpa@zytor.com
Cc: jdelvare@suse.com
Cc: jeremy@goop.org
Cc: linux@roeck-us.net
Cc: pali.rohar@gmail.com
Cc: rusty@rustcorp.com.au
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1472453327-19050-3-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 13:52:38 +02:00
Josh Poimboeuf
4fa8d299b4 sched/debug: Remove several CONFIG_SCHEDSTATS guards
Clean up the sched code by removing several of the CONFIG_SCHEDSTATS
guards, using schedstat_*() macros where needed.

Code size:

  !CONFIG_SCHEDSTATS defconfig:

      text	   data	    bss	     dec	    hex	filename
  10209818	4368184	1105920	15683922	 ef5152	vmlinux.before.nostats
  10209818	4368184	1105920	15683922	 ef5152	vmlinux.after.nostats

  CONFIG_SCHEDSTATS defconfig:

      text	   data	    bss	    dec	    hex	filename
  10214210	4370040	1105920	15690170	 ef69ba	vmlinux.before.stats
  10214210	4370680	1105920	15690810	 ef6c3a	vmlinux.after.stats

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e51e0ebe5af95ac295de720dd252e7c0d2142e4a.1466184592.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 13:29:47 +02:00
Josh Poimboeuf
20e1d4863b sched/debug: Rename 'schedstat_val()' -> 'schedstat_val_or_zero()'
The schedstat_val() macro's behavior is kind of surprising: when
schedstat is runtime disabled, it returns zero.  Rename it to
schedstat_val_or_zero().

There's also a need for a similar macro which doesn't have the 'if
(schedstat_enable())' check, to avoid doing the check twice.  Create a
new 'schedstat_val()' macro for that.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3bb1d2367d041fee333b0dde17171e709395b675.1466184592.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 13:29:46 +02:00
Josh Poimboeuf
ae92882e56 sched/debug: Clean up schedstat macros
The schedstat_*() macros are inconsistent: most of them take a pointer
and a field which the macro combines, whereas schedstat_set() takes the
already combined ptr->field.

The already combined ptr->field argument is actually more intuitive and
easier to use, and there's no reason to require the user to split the
variable up, so convert the macros to use the combined argument.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/54953ca25bb579f3a5946432dee409b0e05222c6.1466184592.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 13:29:46 +02:00
Josh Poimboeuf
1a3d027c5a sched/debug: Rename and move enqueue_sleeper()
enqueue_sleeper() doesn't actually enqueue, it just handles some
statistics and tracepoints.  Rename it to update_stats_enqueue_sleeper()
and call it from update_stats_enqueue().

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fb20b7159dc4d028c406c0e8d5f8c439b741615b.1466184592.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 13:29:45 +02:00