linux.git/kernel/irq/chip.c, branch v3.19

genirq: Work around __irq_set_handler vs stacked domains ordering issues

2014-11-23T12:01:47+00:00

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 
Cc: Yingjoe Chen 
Cc: Bjorn Helgaas 
Cc: linux-arm-kernel@lists.infradead.org
Cc: Jiang Liu 
Link: http://lkml.kernel.org/r/1416048553-29289-3-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner

genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip

2014-11-23T12:01:46+00:00

Add callback irq_compose_msi_msg to struct irq_chip, which will be used
to support stacked irqchip.

Signed-off-by: Jiang Liu 
Cc: Bjorn Helgaas 
Cc: Grant Likely 
Cc: Marc Zyngier 
Cc: Yingjoe Chen 
Cc: Yijing Wang 
Signed-off-by: Thomas Gleixner

genirq: Add more helper functions to support stacked irq_chip

2014-11-23T12:01:46+00:00

Add more helper function for stacked irq_chip to just call parent's
function.

Signed-off-by: Yingjoe Chen 
Cc: Rob Herring 
Cc: Pawel Moll 
Cc: Mark Rutland 
Cc: Matthias Brugger 
Cc: Russell King 
Cc: Jason Cooper 
Cc: Gran Likely 
Cc: Boris BREZILLON 
Cc: 
Cc: Bjorn Helgaas 
Cc: Yijing Wang 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: Sascha Hauer 
Cc: Jiang Liu 
Cc: Marc Zyngier 
Link: http://lkml.kernel.org/r/1415893029-2971-3-git-send-email-yingjoe.chen@mediatek.com
Signed-off-by: Thomas Gleixner

genirq: Introduce helper functions to support stacked irq_chip

2014-11-23T12:01:46+00:00

Now we already support hierarchy irq_data, so introduce several helpers
to support stacked irq_chips.

Signed-off-by: Jiang Liu 
Cc: Bjorn Helgaas 
Cc: Grant Likely 
Cc: Marc Zyngier 
Cc: Yingjoe Chen 
Cc: Yijing Wang 
Signed-off-by: Thomas Gleixner

irqdomain: Introduce new interfaces to support hierarchy irqdomains

2014-11-23T12:01:45+00:00

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 
Cc: Bjorn Helgaas 
Cc: Grant Likely 
Cc: Marc Zyngier 
Cc: Yingjoe Chen 
Cc: Yijing Wang 
Signed-off-by: Thomas Gleixner

Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2014-10-15T05:48:18+00:00

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
...

Merge branch 'pm-genirq'

2014-10-06T23:17:21+00:00

* 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

genirq: Simplify wakeup mechanism

2014-09-01T11:48:59+00:00

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 
[ rjw: syscore.c and put irq_pm_check_wakeup() into pm.c ]
Signed-off-by: Rafael J. Wysocki

genirq: Create helper for flow handler entry check

2014-09-01T11:48:43+00:00

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 
Signed-off-by: Rafael J. Wysocki

genirq: Distangle edge handler entry

2014-09-01T11:48:36+00:00

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 
Signed-off-by: Rafael J. Wysocki