linux-toradex.git/include/linux/irqdesc.h, branch v4.4.4

genirq: Remove irq argument from irq flow handlers

2015-09-16T13:47:51+00:00

Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!

Signed-off-by: Thomas Gleixner 
Cc: Julia Lawall 
Cc: Jiang Liu

genirq: Move field 'msi_desc' from irq_data into irq_common_data

2015-09-16T13:46:49+00:00

MSI descriptors are per-irq instead of per irqchip, so move it into
struct irq_common_data.

Signed-off-by: Jiang Liu 
Cc: Konrad Rzeszutek Wilk 
Cc: Tony Luck 
Cc: Bjorn Helgaas 
Cc: Benjamin Herrenschmidt 
Cc: Randy Dunlap 
Cc: Yinghai Lu 
Cc: Borislav Petkov 
Cc: Jason Cooper 
Cc: Kevin Cernekee 
Cc: Arnd Bergmann 
Cc: Marc Zyngier 
Link: http://lkml.kernel.org/r/1433145945-789-35-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner

genirq: Move field 'handler_data' from irq_data into irq_common_data

2015-09-16T13:46:49+00:00

Handler data (handler_data) is per-irq instead of per irqchip, so move
it into struct irq_common_data.

Signed-off-by: Jiang Liu 
Cc: Konrad Rzeszutek Wilk 
Cc: Tony Luck 
Cc: Bjorn Helgaas 
Cc: Benjamin Herrenschmidt 
Cc: Randy Dunlap 
Cc: Yinghai Lu 
Cc: Borislav Petkov 
Cc: Jason Cooper 
Cc: Kevin Cernekee 
Cc: Arnd Bergmann 
Cc: Marc Zyngier 
Link: http://lkml.kernel.org/r/1433145945-789-13-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner

genirq: Simplify irq_data_to_desc()

2015-09-16T13:43:11+00:00

Avoid the lookup of irq_desc and use the same mechanism for
hierarchical and flat irqdomains.

Based-on-a-patch-from: Jiang Liu 
Signed-off-by: Thomas Gleixner

genirq: Remove __irq_set_handler_locked()

2015-09-16T13:43:11+00:00

All users converted to irq_set_handler_locked()

Signed-off-by: Thomas Gleixner

genirq: Remove __irq_set_chip_handler_name_locked()

2015-09-16T10:55:15+00:00

All users converted to irq_set_chip_handler_name_locked()

Signed-off-by: Thomas Gleixner

genirq: Update the comment for generic_handle_irq_desc

2015-09-15T15:06:30+00:00

__do_IRQ() was removed by commit 1c77ff2 "genirq: Remove __do_IRQ",
but the comment referring to __do_IRQ() was left.

Update the comment for generic_handle_irq_desc().

Signed-off-by: Huang Shijie 
Cc: jiang.liu@linux.intel.com
Cc: peterz@infradead.org
Cc: rafael.j.wysocki@intel.com
Cc: jason@lakedaemon.net
Cc: marc.zyngier@arm.com
Link: http://lkml.kernel.org/r/1441074950-3893-1-git-send-email-shijie.huang@arm.com
Signed-off-by: Thomas Gleixner

genirq: Provide irq_desc_has_action

2015-08-05T22:14:59+00:00

If we have a reference to irq_desc already, there is no point to do
another lookup.

Signed-off-by: Thomas Gleixner 
Cc: Jiang Liu 
Cc: Peter Zijlstra 
Cc: Rusty Russell 
Cc: Bjorn Helgaas 
Link: http://lkml.kernel.org/r/20150802203609.638130301@linutronix.de
Signed-off-by: Thomas Gleixner

hotplug: Prevent alloc/free of irq descriptors during cpu up/down

2015-07-08T09:32:25+00:00

When a cpu goes up some architectures (e.g. x86) have to walk the irq
space to set up the vector space for the cpu. While this needs extra
protection at the architecture level we can avoid a few race
conditions by preventing the concurrent allocation/free of irq
descriptors and the associated data.

When a cpu goes down it moves the interrupts which are targeted to
this cpu away by reassigning the affinities. While this happens
interrupts can be allocated and freed, which opens a can of race
conditions in the code which reassignes the affinities because
interrupt descriptors might be freed underneath.

Example:

CPU1				CPU2
cpu_up/down
 irq_desc = irq_to_desc(irq);
				remove_from_radix_tree(desc);
 raw_spin_lock(&desc->lock);
				free(desc);

We could protect the irq descriptors with RCU, but that would require
a full tree change of all accesses to interrupt descriptors. But
fortunately these kind of race conditions are rather limited to a few
things like cpu hotplug. The normal setup/teardown is very well
serialized. So the simpler and obvious solution is:

Prevent allocation and freeing of interrupt descriptors accross cpu
hotplug.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Cc: xiao jin 
Cc: Joerg Roedel 
Cc: Borislav Petkov 
Cc: Yanmin Zhang 
Link: http://lkml.kernel.org/r/20150705171102.063519515@linutronix.de

genirq: Implement irq_set_handler_locked()/irq_set_chip_handler_name_locked()

2015-06-26T19:32:30+00:00

The main use case for the exisiting __irq_set_*_locked() inlines is to
replace the handler [,chip and name] of an interrupt from a region
which has the irq descriptor lock held, e.g. from the irq_set_type()
callback. The first argument is the irq number, so the functions need
so perform a pointless lookup of the interrupt descriptor for those
cases which have the irq_data pointer handy.

Provide new functions which take an irq_data pointer instead of the
interrupt number, so the lookup of the interrupt descriptor can be
avoided.

Signed-off-by: Thomas Gleixner 
Cc: Jiang Liu 

Conflicts:
	include/linux/irqdesc.h