linux.git/arch/tile/kernel, branch v4.7-rc4

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-05-26T00:05:40+00:00

Pull perf updates from Ingo Molnar:
 "Mostly tooling and PMU driver fixes, but also a number of late updates
  such as the reworking of the call-chain size limiting logic to make
  call-graph recording more robust, plus tooling side changes for the
  new 'backwards ring-buffer' extension to the perf ring-buffer"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  perf record: Read from backward ring buffer
  perf record: Rename variable to make code clear
  perf record: Prevent reading invalid data in record__mmap_read
  perf evlist: Add API to pause/resume
  perf trace: Use the ptr->name beautifier as default for "filename" args
  perf trace: Use the fd->name beautifier as default for "fd" args
  perf report: Add srcline_from/to branch sort keys
  perf evsel: Record fd into perf_mmap
  perf evsel: Add overwrite attribute and check write_backward
  perf tools: Set buildid dir under symfs when --symfs is provided
  perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced
  perf annotate: Sort list of recognised instructions
  perf annotate: Fix identification of ARM blt and bls instructions
  perf tools: Fix usage of max_stack sysctl
  perf callchain: Stop validating callchains by the max_stack sysctl
  perf trace: Fix exit_group() formatting
  perf top: Use machine->kptr_restrict_warned
  perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1
  perf machine: Do not bail out if not managing to read ref reloc symbol
  perf/x86/intel/p4: Trival indentation fix, remove space
  ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

2016-05-24T02:05:11+00:00

Pull arch/tile updates from Chris Metcalf:
 "This is an even quieter cycle than usual"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  Fix typo
  Fix typo
  Fix typo
  tile: sort the "select" lines in the TILE/TILEGX configs
  tile: clarify barrier semantics of atomic_add_return
  tile/defconfigs: Remove CONFIG_IPV6_PRIVACY

Fix typo

2016-05-23T16:17:22+00:00

Signed-off-by: Andrea Gelmini 
Signed-off-by: Chris Metcalf

Fix typo

2016-05-23T16:17:22+00:00

Signed-off-by: Andrea Gelmini 
Signed-off-by: Chris Metcalf

exit_thread: accept a task parameter to be exited

2016-05-21T00:58:30+00:00

We need to call exit_thread from copy_process in a fail path.  So make it
accept task_struct as a parameter.

[v2]
* s390: exit_thread_runtime_instr doesn't make sense to be called for
  non-current tasks.
* arm: fix the comment in vfp_thread_copy
* change 'me' to 'tsk' for task_struct
* now we can change only archs that actually have exit_thread

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jiri Slaby 
Cc: "David S. Miller" 
Cc: "H. Peter Anvin" 
Cc: "James E.J. Bottomley" 
Cc: Aurelien Jacquiot 
Cc: Benjamin Herrenschmidt 
Cc: Catalin Marinas 
Cc: Chen Liqin 
Cc: Chris Metcalf 
Cc: Chris Zankel 
Cc: David Howells 
Cc: Fenghua Yu 
Cc: Geert Uytterhoeven 
Cc: Guan Xuetao 
Cc: Haavard Skinnemoen 
Cc: Hans-Christian Egtvedt 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Ingo Molnar 
Cc: Ivan Kokshaysky 
Cc: James Hogan 
Cc: Jeff Dike 
Cc: Jesper Nilsson 
Cc: Jiri Slaby 
Cc: Jonas Bonn 
Cc: Koichi Yasutake 
Cc: Lennox Wu 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Martin Schwidefsky 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Mikael Starvik 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Ralf Baechle 
Cc: Rich Felker 
Cc: Richard Henderson 
Cc: Richard Kuo 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Steven Miao 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

include/linux/nodemask.h: create next_node_in() helper

2016-05-20T02:12:14+00:00

Lots of code does

	node = next_node(node, XXX);
	if (node == MAX_NUMNODES)
		node = first_node(XXX);

so create next_node_in() to do this and use it in various places.

[mhocko@suse.com: use next_node_in() helper]
Acked-by: Vlastimil Babka 
Acked-by: Michal Hocko 
Signed-off-by: Michal Hocko 
Cc: Xishi Qiu 
Cc: Joonsoo Kim 
Cc: David Rientjes 
Cc: Naoya Horiguchi 
Cc: Laura Abbott 
Cc: Hui Zhu 
Cc: Wang Xiaoqiang 
Cc: Johannes Weiner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

perf core: Pass max stack as a perf_callchain_entry context

2016-05-17T02:11:50+00:00

This makes perf_callchain_{user,kernel}() receive the max stack
as context for the perf_callchain_entry, instead of accessing
the global sysctl_perf_event_max_stack.

Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexei Starovoitov 
Cc: Brendan Gregg 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Milian Wolff 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Cc: Vince Weaver 
Cc: Wang Nan 
Cc: Zefan Li 
Link: http://lkml.kernel.org/n/tip-kolmn1yo40p7jhswxwrc7rrd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

2016-03-28T20:04:55+00:00

Pull arch/tile bugfixes from Chris Metcalf:
 "These include updates to MAINTAINERS, some comment spelling fixes, and
  a bugfix to the tile kgdb.c support"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: Fix misspellings in comments.
  MAINTAINERS: update web link for tile architecture
  MAINTAINERS: update arch/tile maintainer email domain
  tile kgdb: fix bug in copy to gdb regs, and optimize memset

arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections

2016-03-25T23:37:42+00:00

KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to  so that the
users don't need to pull in .  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko 
Acked-by: Steven Rostedt 
Cc: Christoph Lameter 
Cc: Pekka Enberg 
Cc: David Rientjes 
Cc: Joonsoo Kim 
Cc: Andrey Konovalov 
Cc: Dmitry Vyukov 
Cc: Andrey Ryabinin 
Cc: Konstantin Serebryany 
Cc: Dmitry Chernenkov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-03-15T20:50:29+00:00

Pull cpu hotplug updates from Thomas Gleixner:
"This is the first part of the ongoing cpu hotplug rework:

- Initial implementation of the state machine

- Runs all online and prepare down callbacks on the plugged cpu and
not on some random processor

- Replaces busy loop waiting with completions

- Adds tracepoints so the states can be followed"

More detailed commentary on this work from an earlier email:
"What's wrong with the current cpu hotplug infrastructure?

- Asymmetry

The hotplug notifier mechanism is asymmetric versus the bringup and
teardown. This is mostly caused by the notifier mechanism.

- Largely undocumented dependencies

While some notifiers use explicitely defined notifier priorities,
we have quite some notifiers which use numerical priorities to
express dependencies without any documentation why.

- Control processor driven

Most of the bringup/teardown of a cpu is driven by a control
processor. While it is understandable, that preperatory steps,
like idle thread creation, memory allocation for and initialization
of essential facilities needs to be done before a cpu can boot,
there is no reason why everything else must run on a control
processor. Before this patch series, bringup looks like this:

Control CPU Booting CPU

do preparatory steps
kick cpu into life

do low level init

sync with booting cpu sync with control cpu

bring the rest up

- All or nothing approach

There is no way to do partial bringups. That's something which is
really desired because we waste e.g. at boot substantial amount of
time just busy waiting that the cpu comes to life. That's stupid
as we could very well do preparatory steps and the initial IPI for
other cpus and then go back and do the necessary low level
synchronization with the freshly booted cpu.

- Minimal debuggability

Due to the notifier based design, it's impossible to switch between
two stages of the bringup/teardown back and forth in order to test
the correctness. So in many hotplug notifiers the cancel
mechanisms are either not existant or completely untested.

- Notifier [un]registering is tedious

To [un]register notifiers we need to protect against hotplug at
every callsite. There is no mechanism that bringup/teardown
callbacks are issued on the online cpus, so every caller needs to
do it itself. That also includes error rollback.

What's the new design?

The base of the new design is a symmetric state machine, where both
the control processor and the booting/dying cpu execute a well
defined set of states. Each state is symmetric in the end, except
for some well defined exceptions, and the bringup/teardown can be
stopped and reversed at almost all states.

So the bringup of a cpu will look like this in the future:

Control CPU Booting CPU

do preparatory steps
kick cpu into life

do low level init

sync with booting cpu sync with control cpu

bring itself up

The synchronization step does not require the control cpu to wait.
That mechanism can be done asynchronously via a worker or some
other mechanism.

The teardown can be made very similar, so that the dying cpu cleans
up and brings itself down. Cleanups which need to be done after
the cpu is gone, can be scheduled asynchronously as well.

There is a long way to this, as we need to refactor the notion when a
cpu is available. Today we set the cpu online right after it comes
out of the low level bringup, which is not really correct.

The proper mechanism is to set it to available, i.e. cpu local
threads, like softirqd, hotplug thread etc. can be scheduled on that
cpu, and once it finished all booting steps, it's set to online, so
general workloads can be scheduled on it. The reverse happens on
teardown. First thing to do is to forbid scheduling of general
workloads, then teardown all the per cpu resources and finally shut it
off completely.

This patch series implements the basic infrastructure for this at the
core level. This includes the following:

- Basic state machine implementation with well defined states, so
ordering and prioritization can be expressed.

- Interfaces to [un]register state callbacks

This invokes the bringup/teardown callback on all online cpus with
the proper protection in place and [un]installs the callbacks in
the state machine array.

For callbacks which have no particular ordering requirement we have
a dynamic state space, so that drivers don't have to register an
explicit hotplug state.

If a callback fails, the code automatically does a rollback to the
previous state.

- Sysfs interface to drive the state machine to a particular step.

This is only partially functional today. Full functionality and
therefor testability will be achieved once we converted all
existing hotplug notifiers over to the new scheme.

- Run all CPU_ONLINE/DOWN_PREPARE notifiers on the booting/dying
processor:

Control CPU Booting CPU

do preparatory steps
kick cpu into life

do low level init

sync with booting cpu sync with control cpu
wait for boot
bring itself up

Signal completion to control cpu

In a previous step of this work we've done a full tree mechanical
conversion of all hotplug notifiers to the new scheme. The balance
is a net removal of about 4000 lines of code.

This is not included in this series, as we decided to take a
different approach. Instead of mechanically converting everything
over, we will do a proper overhaul of the usage sites one by one so
they nicely fit into the symmetric callback scheme.

I decided to do that after I looked at the ugliness of some of the
converted sites and figured out that their hotplug mechanism is
completely buggered anyway. So there is no point to do a
mechanical conversion first as we need to go through the usage
sites one by one again in order to achieve a full symmetric and
testable behaviour"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
cpu/hotplug: Document states better
cpu/hotplug: Fix smpboot thread ordering
cpu/hotplug: Remove redundant state check
cpu/hotplug: Plug death reporting race
rcu: Make CPU_DYING_IDLE an explicit call
cpu/hotplug: Make wait for dead cpu completion based
cpu/hotplug: Let upcoming cpu bring itself fully up
arch/hotplug: Call into idle with a proper state
cpu/hotplug: Move online calls to hotplugged cpu
cpu/hotplug: Create hotplug threads
cpu/hotplug: Split out the state walk into functions
cpu/hotplug: Unpark smpboot threads from the state machine
cpu/hotplug: Move scheduler cpu_online notifier to hotplug core
cpu/hotplug: Implement setup/removal interface
cpu/hotplug: Make target state writeable
cpu/hotplug: Add sysfs state interface
cpu/hotplug: Hand in target state to _cpu_up/down
cpu/hotplug: Convert the hotplugged cpu work to a state machine
cpu/hotplug: Convert to a state machine for the control processor
cpu/hotplug: Add tracepoints
...