Commit Graph

171 Commits

Author SHA1 Message Date
Marc Zyngier f86eff222f genirq: Work around __irq_set_handler vs stacked domains ordering issues
With the introduction of stacked domains, we have the issue that,
depending on where in the stack this is called, __irq_set_handler
will succeed or fail: If this is called from the inner irqchip,
__irq_set_handler() will fail, as it will look at the outer domain
as the (desc->irq_data.chip == &no_irq_chip) test fails (we haven't
set the top level yet).

This patch implements the following: "If there is at least one
valid irqchip in the domain, it will probably sort itself out".
This is clearly not ideal, but it is far less confusing then
crashing because the top-level domain is not up yet.

[ tglx: Added comment and a protection against chained interrupts in
  	that context ]

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Link: http://lkml.kernel.org/r/1416048553-29289-3-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-23 13:01:47 +01:00
Jiang Liu 515085ef7e genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip
Add callback irq_compose_msi_msg to struct irq_chip, which will be used
to support stacked irqchip.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-23 13:01:46 +01:00
Yingjoe Chen 56e8abab61 genirq: Add more helper functions to support stacked irq_chip
Add more helper function for stacked irq_chip to just call parent's
function.

Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Gran Likely <grant.likely@linaro.org>
Cc: Boris BREZILLON <boris.brezillon@free-electrons.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: <srv_heupstream@mediatek.com>
Cc: <yingjoe.chen@gmail.com>
Cc: <hc.yen@mediatek.com>
Cc: <eddie.huang@mediatek.com>
Cc: <nathan.chung@mediatek.com>
Cc: <yh.chen@mediatek.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1415893029-2971-3-git-send-email-yingjoe.chen@mediatek.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-23 13:01:46 +01:00
Jiang Liu 85f08c17de genirq: Introduce helper functions to support stacked irq_chip
Now we already support hierarchy irq_data, so introduce several helpers
to support stacked irq_chips.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-23 13:01:46 +01:00
Jiang Liu f8264e3496 irqdomain: Introduce new interfaces to support hierarchy irqdomains
We plan to use hierarchy irqdomain to suppport CPU vector assignment,
interrupt remapping controller, IO-APIC controller, MSI interrupt
and hypertransport interrupt etc on x86 platforms. So extend irqdomain
interfaces to support hierarchy irqdomain.

There are already many clients of current irqdomain interfaces.
To minimize the changes, we choose to introduce new version 2 interfaces
to support hierarchy instead of extending existing irqdomain interfaces.

According to Thomas's suggestion, the most important design decision is
to build hierarchy struct irq_data to support hierarchy irqdomain, so
hierarchy irqdomain related data could be saved in struct irq_data.
With support of hierarchy irq_data, we could also support stacked
irq_chips. This is most useful in case of set_affinity().

The new hierarchy irqdomain introduces following interfaces:
1) irq_domain_alloc_irqs()/irq_domain_free_irqs(): allocate/release IRQ
   and related resources.
2) __irq_domain_alloc_irqs(): a special version to support legacy IRQs.
3) irq_domain_activate_irq()/irq_domain_deactivate_irq(): program
   interrupt controllers to activate/deactivate interrupt.

There are also several help functions to ease irqdomain implemenations:
1) irq_domain_get_irq_data(): get irq_data associated with a specific
   irqdomain.
2) irq_domain_set_hwirq_and_chip(): save irqdomain specific data into
   irq_data.
3) irq_domain_alloc_irqs_parent()/irq_domain_free_irqs_parent(): invoke
   parent irqdomain's alloc/free callbacks.

We also changed irq_startup()/irq_shutdown() to invoke
irq_domain_activate_irq()/irq_domain_deactivate_irq() to program
interrupt controller when start/stop interrupts.

[ tglx: Folded parts of the later patch series in ]

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-23 13:01:45 +01:00
Linus Torvalds 0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Rafael J. Wysocki 88b42a4883 Merge branch 'pm-genirq'
* pm-genirq:
  PM / genirq: Document rules related to system suspend and interrupts
  PCI / PM: Make PCIe PME interrupts wake up from suspend-to-idle
  x86 / PM: Set IRQCHIP_SKIP_SET_WAKE for IOAPIC IRQ chip objects
  genirq: Simplify wakeup mechanism
  genirq: Mark wakeup sources as armed on suspend
  genirq: Create helper for flow handler entry check
  genirq: Distangle edge handler entry
  genirq: Avoid double loop on suspend
  genirq: Move MASK_ON_SUSPEND handling into suspend_device_irqs()
  genirq: Make use of pm misfeature accounting
  genirq: Add sanity checks for PM options on shared interrupt lines
  genirq: Move suspend/resume logic into irq/pm code
  PM / sleep: Mechanism for aborting system suspends unconditionally
2014-10-07 01:17:21 +02:00
Thomas Gleixner 9ce7a25849 genirq: Simplify wakeup mechanism
Currently we suspend wakeup interrupts by lazy disabling them and
check later whether the interrupt has fired, but that's not sufficient
for suspend to idle as there is no way to check that once we
transitioned into the CPU idle state.

So we change the mechanism in the following way:

1) Leave the wakeup interrupts enabled across suspend

2) Add a check to irq_may_run() which is called at the beginning of
   each flow handler whether the interrupt is an armed wakeup source.

   This check is basically free as it just extends the existing check
   for IRQD_IRQ_INPROGRESS. So no new conditional in the hot path.

   If the IRQD_WAKEUP_ARMED flag is set, then the interrupt is
   disabled, marked as pending/suspended and the pm core is notified
   about the wakeup event.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ rjw: syscore.c and put irq_pm_check_wakeup() into pm.c ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-01 13:48:59 +02:00
Thomas Gleixner c7bd3ec053 genirq: Create helper for flow handler entry check
All flow handlers - except the per cpu ones - check for an interrupt
in progress and an eventual concurrent polling on another cpu.

Create a helper function for the repeated code pattern.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-01 13:48:43 +02:00
Thomas Gleixner c3d7acd027 genirq: Distangle edge handler entry
If the interrupt is disabled or has no action, then we should not call
the poll check. Separate the checks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-01 13:48:36 +02:00
Christoph Lameter 532d0d0690 irqchips: Replace __this_cpu_ptr uses
[ARM specific]

These are generally replaced with raw_cpu_ptr. However, in
gic_get_percpu_base() we immediately dereference the pointer. This is
equivalent to a raw_cpu_read. So use that operation there.

Cc: nicolas.pitre@linaro.org
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:48 -04:00
Vincent Stehlé 7cad45eea3 irq: Export handle_fasteoi_irq
Export handle_fasteoi_irq to be able to use it in e.g. the Zynq gpio driver
since commit 6dd8595083 ("gpio: zynq: Fix IRQ handlers").

This fixes the following link issue:

  ERROR: "handle_fasteoi_irq" [drivers/gpio/gpio-zynq.ko] undefined!

Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Vincent Stehle <vincent.stehle@laposte.net>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Link: http://lkml.kernel.org/r/1408663880-29179-1-git-send-email-vincent.stehle@laposte.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-08-25 21:13:30 +02:00
Thomas Gleixner f63b6a05f2 genirq: Replace reserve_irqs in core code
We want to get rid of the public interface.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140507154340.061990194@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16 14:05:22 +02:00
Thomas Gleixner 328a4978df genirq: Add a new IRQCHIP_EOI_THREADED flag
The flag is necessary for interrupt chips which require an ACK/EOI
after the handler has run. In case of threaded handlers this needs to
happen after the threaded handler has completed before the unmask of
the interrupt.

The flag is only unseful in combination with the handle_fasteoi_irq
flow control handler.

It can be combined with the flag IRQCHIP_EOI_IF_HANDLED, so the EOI is
not issued when the interrupt is disabled or in progress.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-sunxi@googlegroups.com
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/1394733834-26839-2-git-send-email-hdegoede@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-14 13:43:33 +01:00
Xie XiuQi f788e7bf05 irq: Fix some trivial typos in comments
Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
[jkosina@suse.cz: fix 'explicitly', noticed by Randy Dunlap]
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-10-18 14:49:30 +02:00
Andreas Fenkart d671a60558 genirq: Add kerneldoc for irq_disable.
Document the lazy disable functionality. comment based on changelog of
d209a699a0

Signed-off-by: Andreas Fenkart <andreas.fenkart@streamunlimited.com>
Cc: balbi@ti.com
Link: http://lkml.kernel.org/r/1368181290-1583-1-git-send-email-andreas.fenkart@streamunlimited.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-29 11:09:10 +02:00
Alexander Gordeev 51906e779f x86/MSI: Support multiple MSIs in presense of IRQ remapping
The MSI specification has several constraints in comparison with
MSI-X, most notable of them is the inability to configure MSIs
independently. As a result, it is impossible to dispatch
interrupts from different queues to different CPUs. This is
largely devalues the support of multiple MSIs in SMP systems.

Also, a necessity to allocate a contiguous block of vector
numbers for devices capable of multiple MSIs might cause a
considerable pressure on x86 interrupt vector allocator and
could lead to fragmentation of the interrupt vectors space.

This patch overcomes both drawbacks in presense of IRQ remapping
and lets devices take advantage of multiple queues and per-IRQ
affinity assignments.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c8bd86ff56b5fc118257436768aaa04489ac0a4c.1353324359.git.agordeev@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-24 17:25:12 +01:00
Thomas Gleixner 293a7a0a16 genirq: Provide means to retrigger parent
Attempts to retrigger nested threaded IRQs currently fail because they
have no primary handler. In order to support retrigger of nested
IRQs, the parent IRQ needs to be retriggered.

To fix, when an IRQ needs to be resent, if the interrupt has a parent
IRQ and runs in the context of the parent IRQ, then resend the parent.

Also, handle_nested_irq() needs to clear the replay flag like the
other handlers, otherwise check_irq_resend() will set it and it will
never be cleared.  Without clearing, it results in the first resend
working fine, but check_irq_resend() returning early on subsequent
resends because the replay flag is still set.

Problem discovered on ARM/OMAP platforms where a nested IRQ that's
also a wakeup IRQ happens late in suspend and needed to be retriggered
during the resume process.

[khilman@ti.com: changelog edits, clear IRQS_REPLAY in handle_nested_irq()]

Reported-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1350425269-11489-1-git-send-email-khilman@deeprootsystems.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-11-01 12:11:31 +01:00
Kuninori Morimoto b3ae66f209 genirq: Export irq_set_chip_and_handler_name()
Export irq_set_chip_and_handler_name() to modules to allow them to
do things such as

	irq_set_chip_and_handler(....);

This fixes

	ERROR: "irq_set_chip_and_handler_name" \
	          [drivers/gpio/gpio-pcf857x.ko] undefined!

when gpio-pcf857x.c is being built as a module.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Greg KH <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/873948trpk.wl%25kuninori.morimoto.gx@renesas.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21 16:14:23 +02:00
Ning Jiang 23812b9d9e genirq: Add IRQS_PENDING for nested and simple irq
Every interrupt which is an active wakeup source needs the ability to
abort suspend if there is a pending irq. Right now only edge and level
irqs can do that.

            |
       +---------+
       |   INTC  |
       +---------+
               | GPIO_IRQ
            +------------+
            |  gpio-exp  |
            +------------+
              |        |
         GPIO0_IRQ  GPIO1_IRQ

In the above diagram, gpio expander has irq number GPIO_IRQ, it is
connected with two sub GPIO pins, GPIO0 and GPIO1.

During suspend, we set IRQF_NO_SUSPEND for GPIO_IRQ so that gpio
expander driver can handle the sub irq GPIO0_IRQ and GPIO1_IRQ, and
these two irqs themselves can further be handled by simple or nested
irq in some drivers(typically gpio and mfd driver). If they are used
as wakeup sources during suspend, we want them to be able to abort
suspend too.

Setting IRQS_PENDING flag in handle_nested_irq() and handle_simple_irq()
when the irq is disabled allows check_wakeup_irqs() to identify such
irqs as source for aborting suspend.

Signed-off-by: Ning Jiang <ning.n.jiang@gmail.com>
Cc: rjw@sisk.pl
Link: http://lkml.kernel.org/r/CAH3Oq6T905%2B3fkF43NAMMFvJvq7dsk_so6T2vQ8ZJrA5xiU3YA@mail.gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-24 22:27:45 +02:00
Linus Torvalds 471368557a Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core irq changes from Ingo Molnar:
 "A collection of small fixes."

By Thomas Gleixner
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hexagon: Remove select of not longer existing Kconfig switches
  arm: Select core options instead of redefining them
  genirq: Do not consider disabled wakeup irqs
  genirq: Allow check_wakeup_irqs to notice level-triggered interrupts
  genirq: Be more informative on irq type mismatch
  genirq: Reject bogus threaded irq requests
  genirq: Streamline irq_action
2012-05-21 20:33:19 -07:00
Jiri Kosina 3911ff30f5 genirq: export handle_edge_irq() and irq_to_desc()
Export handle_edge_irq() and irq_to_desc() to modules to allow them to
do things such as

	__irq_set_handler_locked(...., handle_edge_irq);

This fixes

	ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined!
	ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined!

when gpio-pch is being built as a module.

This was introduced by commit df9541a60a ("gpio: pch9: Use proper flow
type handlers") that added

	__irq_set_handler_locked(d->irq, handle_edge_irq);

but handle_edge_irq() was not exported for modules (and inlined
__irq_set_handler_locked() requires irq_to_desc() exported as well)

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-15 08:10:07 -07:00
Thomas Gleixner d4dc0f90d2 genirq: Allow check_wakeup_irqs to notice level-triggered interrupts
Level triggered interrupts do not cause IRQS_PENDING to be set when
they fire while "disabled" as the 'pending' state is always present in
the level - they automatically refire where re-enabled.

However the IRQS_PENDING flag is also used to abort a suspend cycle -
if any 'is_wakeup_set' interrupt is PENDING, check_wakeup_irqs() will
cause suspend to abort. Without IRQS_PENDING, suspend won't abort.

Consequently, level-triggered interrupts that fire during the 'noirq'
phase of suspend do not currently abort suspend.

So set IRQS_PENDING even for level triggered interrupts, and make sure
to clear the flag in check_irq_resend.

[ Changelog by courtesy of Neil ]

Tested-by: NeilBrown <neilb@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-04 23:38:50 +02:00
Linus Torvalds 9c2b957db1 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events changes for v3.4 from Ingo Molnar:

 - New "hardware based branch profiling" feature both on the kernel and
   the tooling side, on CPUs that support it.  (modern x86 Intel CPUs
   with the 'LBR' hardware feature currently.)

   This new feature is basically a sophisticated 'magnifying glass' for
   branch execution - something that is pretty difficult to extract from
   regular, function histogram centric profiles.

   The simplest mode is activated via 'perf record -b', and the result
   looks like this in perf report:

	$ perf record -b any_call,u -e cycles:u branchy

	$ perf report -b --sort=symbol
	    52.34%  [.] main                   [.] f1
	    24.04%  [.] f1                     [.] f3
	    23.60%  [.] f1                     [.] f2
	     0.01%  [k] _IO_new_file_xsputn    [k] _IO_file_overflow
	     0.01%  [k] _IO_vfprintf_internal  [k] _IO_new_file_xsputn
	     0.01%  [k] _IO_vfprintf_internal  [k] strchrnul
	     0.01%  [k] __printf               [k] _IO_vfprintf_internal
	     0.01%  [k] main                   [k] __printf

   This output shows from/to branch columns and shows the highest
   percentage (from,to) jump combinations - i.e.  the most likely taken
   branches in the system.  "branches" can also include function calls
   and any other synchronous and asynchronous transitions of the
   instruction pointer that are not 'next instruction' - such as system
   calls, traps, interrupts, etc.

   This feature comes with (hopefully intuitive) flat ascii and TUI
   support in perf report.

 - Various 'perf annotate' visual improvements for us assembly junkies.
   It will now recognize function calls in the TUI and by hitting enter
   you can follow the call (recursively) and back, amongst other
   improvements.

 - Multiple threads/processes recording support in perf record, perf
   stat, perf top - which is activated via a comma-list of PIDs:

	perf top -p 21483,21485
	perf stat -p 21483,21485 -ddd
	perf record -p 21483,21485

 - Support for per UID views, via the --uid paramter to perf top, perf
   report, etc.  For example 'perf top --uid mingo' will only show the
   tasks that I am running, excluding other users, root, etc.

 - Jump label restructurings and improvements - this includes the
   factoring out of the (hopefully much clearer) include/linux/static_key.h
   generic facility:

	struct static_key key = STATIC_KEY_INIT_FALSE;

	...

	if (static_key_false(&key))
	        do unlikely code
	else
	        do likely code

	...
	static_key_slow_inc();
	...
	static_key_slow_inc();
	...

   The static_key_false() branch will be generated into the code with as
   little impact to the likely code path as possible.  the
   static_key_slow_*() APIs flip the branch via live kernel code patching.

   This facility can now be used more widely within the kernel to
   micro-optimize hot branches whose likelihood matches the static-key
   usage and fast/slow cost patterns.

 - SW function tracer improvements: perf support and filtering support.

 - Various hardenings of the perf.data ABI, to make older perf.data's
   smoother on newer tool versions, to make new features integrate more
   smoothly, to support cross-endian recording/analyzing workflows
   better, etc.

 - Restructuring of the kprobes code, the splitting out of 'optprobes',
   and a corner case bugfix.

 - Allow the tracing of kernel console output (printk).

 - Improvements/fixes to user-space RDPMC support, allowing user-space
   self-profiling code to extract PMU counts without performing any
   system calls, while playing nice with the kernel side.

 - 'perf bench' improvements

 - ... and lots of internal restructurings, cleanups and fixes that made
   these features possible.  And, as usual this list is incomplete as
   there were also lots of other improvements

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
  perf report: Fix annotate double quit issue in branch view mode
  perf report: Remove duplicate annotate choice in branch view mode
  perf/x86: Prettify pmu config literals
  perf report: Enable TUI in branch view mode
  perf report: Auto-detect branch stack sampling mode
  perf record: Add HEADER_BRANCH_STACK tag
  perf record: Provide default branch stack sampling mode option
  perf tools: Make perf able to read files from older ABIs
  perf tools: Fix ABI compatibility bug in print_event_desc()
  perf tools: Enable reading of perf.data files from different ABI rev
  perf: Add ABI reference sizes
  perf report: Add support for taken branch sampling
  perf record: Add support for sampling taken branch
  perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
  x86/kprobes: Split out optprobe related code to kprobes-opt.c
  x86/kprobes: Fix a bug which can modify kernel code permanently
  x86/kprobes: Fix instruction recovery on optimized path
  perf: Add callback to flush branch_stack on context switch
  perf: Disable PERF_SAMPLE_BRANCH_* when not supported
  perf/x86: Add LBR software filter support for Intel CPUs
  ...
2012-03-20 10:29:15 -07:00
Thomas Gleixner df8d291f28 Merge branch 'linus' into irq/core
Reason: Get upstream fixes integrated before further modifications.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-13 16:35:16 +01:00