17 Oct, 2011
1 commit
-
This adds a mechanism to resume selected IRQs during syscore_resume
instead of dpm_resume_noirq.Under Xen we need to resume IRQs associated with IPIs early enough
that the resched IPI is unmasked and we can therefore schedule
ourselves out of the stop_machine where the suspend/resume takes
place.This issue was introduced by 676dc3cf5bc3 "xen: Use IRQF_FORCE_RESUME".
Signed-off-by: Ian Campbell
Cc: Rafael J. Wysocki
Cc: Jeremy Fitzhardinge
Cc: xen-devel
Cc: Konrad Rzeszutek Wilk
Link: http://lkml.kernel.org/r/1318713254.11016.52.camel@dagon.hellion.org.uk
Cc: stable@kernel.org (at least to 2.6.32.y)
Signed-off-by: Thomas Gleixner
03 Oct, 2011
2 commits
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As request_percpu_irq() doesn't allow for a percpu interrupt to have
its type configured (it is generally impossible to configure it on all
CPUs at once), add a 'type' argument to enable_percpu_irq().This allows some low-level, board specific init code to be switched to
a generic API.[ tglx: Added WARN_ON argument ]
Signed-off-by: Marc Zyngier
Cc: Abhijeet Dharmapurikar
Signed-off-by: Thomas Gleixner -
The ARM GIC interrupt controller offers per CPU interrupts (PPIs),
which are usually used to connect local timers to each core. Each CPU
has its own private interface to the GIC, and only sees the PPIs that
are directly connect to it.While these timers are separate devices and have a separate interrupt
line to a core, they all use the same IRQ number.For these devices, request_irq() is not the right API as it assumes
that an IRQ number is visible by a number of CPUs (through the
affinity setting), but makes it very awkward to express that an IRQ
number can be handled by all CPUs, and yet be a different interrupt
line on each CPU, requiring a different dev_id cookie to be passed
back to the handler.The *_percpu_irq() functions is designed to overcome these
limitations, by providing a per-cpu dev_id vector:int request_percpu_irq(unsigned int irq, irq_handler_t handler,
const char *devname, void __percpu *percpu_dev_id);
void free_percpu_irq(unsigned int, void __percpu *);
int setup_percpu_irq(unsigned int irq, struct irqaction *new);
void remove_percpu_irq(unsigned int irq, struct irqaction *act);
void enable_percpu_irq(unsigned int irq);
void disable_percpu_irq(unsigned int irq);The API has a number of limitations:
- no interrupt sharing
- no threading
- common handler across all the CPUsOnce the interrupt is requested using setup_percpu_irq() or
request_percpu_irq(), it must be enabled by each core that wishes its
local interrupt to be delivered.Based on an initial patch by Thomas Gleixner.
Signed-off-by: Marc Zyngier
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1316793788-14500-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner
27 Jul, 2011
1 commit
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This allows us to move duplicated code in
(atomic_inc_not_zero() for now) toSigned-off-by: Arun Sharma
Reviewed-by: Eric Dumazet
Cc: Ingo Molnar
Cc: David Miller
Cc: Eric Dumazet
Acked-by: Mike Frysinger
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Jun, 2011
1 commit
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Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread)
introduced performance regression. In an AIM7 test, this commit degraded
performance by about 40%.The commit runs rcu callbacks in a kthread instead of softirq. We observed
high rate of context switch which is caused by this. Out test system has
64 CPUs and HZ is 1000, so we saw more than 64k context switch per second
which is caused by RCU's per-CPU kthread. A trace showed that most of
the time the RCU per-CPU kthread doesn't actually handle any callbacks,
but instead just does a very small amount of work handling grace periods.
This means that RCU's per-CPU kthreads are making the scheduler do quite
a bit of work in order to allow a very small amount of RCU-related
processing to be done.Alex Shi's analysis determined that this slowdown is due to lock
contention within the scheduler. Unfortunately, as Peter Zijlstra points
out, the scheduler's real-time semantics require global action, which
means that this contention is inherent in real-time scheduling. (Yes,
perhaps someone will come up with a workaround -- otherwise, -rt is not
going to do well on large SMP systems -- but this patch will work around
this issue in the meantime. And "the meantime" might well be forever.)This patch therefore re-introduces softirq processing to RCU, but only
for core RCU work. RCU callbacks are still executed in kthread context,
so that only a small amount of RCU work runs in softirq context in the
common case. This should minimize ksoftirqd execution, allowing us to
skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels.Signed-off-by: Shaohua Li
Tested-by: "Alex,Shi"
Signed-off-by: Paul E. McKenney
06 May, 2011
1 commit
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If RCU priority boosting is to be meaningful, callback invocation must
be boosted in addition to preempted RCU readers. Otherwise, in presence
of CPU real-time threads, the grace period ends, but the callbacks don't
get invoked. If the callbacks don't get invoked, the associated memory
doesn't get freed, so the system is still subject to OOM.But it is not reasonable to priority-boost RCU_SOFTIRQ, so this commit
moves the callback invocations to a kthread, which can be boosted easily.Also add comments and properly synchronized all accesses to
rcu_cpu_kthread_task, as suggested by Lai Jiangshan.Signed-off-by: Paul E. McKenney
Signed-off-by: Paul E. McKenney
Reviewed-by: Josh Triplett
31 Mar, 2011
1 commit
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Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: Lucas De Marchi
30 Mar, 2011
1 commit
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Missed that one in the big compat remval patch
Signed-off-by: Thomas Gleixner
16 Mar, 2011
2 commits
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* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (116 commits)
x86: Enable forced interrupt threading support
x86: Mark low level interrupts IRQF_NO_THREAD
x86: Use generic show_interrupts
x86: ioapic: Avoid redundant lookup of irq_cfg
x86: ioapic: Use new move_irq functions
x86: Use the proper accessors in fixup_irqs()
x86: ioapic: Use irq_data->state
x86: ioapic: Simplify irq chip and handler setup
x86: Cleanup the genirq name space
genirq: Add chip flag to force mask on suspend
genirq: Add desc->irq_data accessor
genirq: Add comments to Kconfig switches
genirq: Fixup fasteoi handler for oneshot mode
genirq: Provide forced interrupt threading
sched: Switch wait_task_inactive to schedule_hrtimeout()
genirq: Add IRQF_NO_THREAD
genirq: Allow shared oneshot interrupts
genirq: Prepare the handling of shared oneshot interrupts
genirq: Make warning in handle_percpu_event useful
x86: ioapic: Move trigger defines to io_apic.h
...Fix up trivial(?) conflicts in arch/x86/pci/xen.c due to genirq name
space changes clashing with the Xen cleanups. The set_irq_msi() had
moved to xen_bind_pirq_msi_to_irq(). -
…/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits)
sched: Resched proper CPU on yield_to()
sched: Allow users with sufficient RLIMIT_NICE to change from SCHED_IDLE policy
sched: Allow SCHED_BATCH to preempt SCHED_IDLE tasks
sched: Clean up the IRQ_TIME_ACCOUNTING code
sched: Add #ifdef around irq time accounting functions
sched, autogroup: Stop claiming ownership of the root task group
sched, autogroup: Stop going ahead if autogroup is disabled
sched, autogroup, sysctl: Use proc_dointvec_minmax() instead
sched: Fix the group_imb logic
sched: Clean up some f_b_g() comments
sched: Clean up remnants of sd_idle
sched: Wholesale removal of sd_idle logic
sched: Add yield_to(task, preempt) functionality
sched: Use a buddy to implement yield_task_fair()
sched: Limit the scope of clear_buddies
sched: Check the right ->nr_running in yield_task_fair()
sched: Avoid expensive initial update_cfs_load(), on UP too
sched: Fix switch_from_fair()
sched: Simplify the idle scheduling class
softirqs: Account ksoftirqd time as cpustat softirq
...
26 Feb, 2011
3 commits
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Add a commandline parameter "threadirqs" which forces all interrupts except
those marked IRQF_NO_THREAD to run threaded. That's mostly a debug option to
allow retrieving better debug data from crashing interrupt handlers. If
"threadirqs" is not enabled on the kernel command line, then there is no
impact in the interrupt hotpath.Architecture code needs to select CONFIG_IRQ_FORCED_THREADING after
marking the interrupts which cant be threaded IRQF_NO_THREAD. All
interrupts which have IRQF_TIMER set are implict marked
IRQF_NO_THREAD. Also all PER_CPU interrupts are excluded.Forced threading hard interrupts also forces all soft interrupt
handling into thread context.When enabled it might slow down things a bit, but for debugging problems in
interrupt code it's a reasonable penalty as it does not immediately
crash and burn the machine when an interrupt handler is buggy.Some test results on a Core2Duo machine:
Cache cold run of:
# time git grep irq_descnon-threaded threaded
real 1m18.741s 1m19.061s
user 0m1.874s 0m1.757s
sys 0m5.843s 0m5.427s# iperf -c server
non-threaded
[ 3] 0.0-10.0 sec 1.09 GBytes 933 Mbits/sec
[ 3] 0.0-10.0 sec 1.09 GBytes 934 Mbits/sec
[ 3] 0.0-10.0 sec 1.09 GBytes 933 Mbits/sec
threaded
[ 3] 0.0-10.0 sec 1.09 GBytes 939 Mbits/sec
[ 3] 0.0-10.0 sec 1.09 GBytes 934 Mbits/sec
[ 3] 0.0-10.0 sec 1.09 GBytes 937 Mbits/secSigned-off-by: Thomas Gleixner
Cc: Peter Zijlstra
LKML-Reference: -
Some low level interrupts cannot be threaded even when we force thread
all interrupt handlers. Add a flag to annotate such interrupts. Add
all timer interrupts to this category by default.Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
LKML-Reference: -
For level type interrupts we need to track how many threads are on
flight to avoid useless interrupt storms when not all thread handlers
have finished yet. Keep track of the woken threads and only unmask
when there are no more threads in flight.Yes, I'm lazy and using a bitfield. But not only because I'm lazy, the
main reason is that it's way simpler than using a refcount. A refcount
based solution would need to keep track of various things like
crashing the irq thread, spurious interrupts coming in,
disables/enables, free_irq() and some more. The bitfield keeps the
tracking simple and makes things just work. It's also nicely confined
to the thread code pathes and does not require additional checks all
over the place.Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
LKML-Reference:
19 Feb, 2011
3 commits
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All archs implement show_interrupts() in more or less the same
way. That's tons of duplicated code with different bugs with no
value. Implement a generic version and deprecate show_interrupts()Unfortunately we need some ifdeffery for !GENERIC_HARDIRQ archs.
Signed-off-by: Thomas Gleixner
-
Soleley used in core code.
Signed-off-by: Thomas Gleixner
-
The irq namespace has become quite convoluted. My bad. Clean it up
and deprecate the old functions. All new functions follow the scheme:irq number based:
irq_set/get/xxx/_xxx(unsigned int irq, ...)irq_data based:
irq_data_set/get/xxx/_xxx(struct irq_data *d, ....)irq_desc based:
irq_desc_get_xxx(struct irq_desc *desc)Signed-off-by: Thomas Gleixner
08 Feb, 2011
2 commits
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irq/for-xen contains new functionality to avoid Xen private irq
hackery. That branch has a single irq commit and is pulled by Xen to
base their new features on.Merge it into irq/core as other patches modify the same code.
Signed-off-by: Thomas Gleixner
-
Xen needs to reenable interrupts which are marked IRQF_NO_SUSPEND in the
resume path. Add a flag to force the reenabling in the resume code.Tested-and-acked-by: Ian Campbell
Signed-off-by: Thomas Gleixner
26 Jan, 2011
1 commit
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Cleanup patch, freeing up PF_KSOFTIRQD and use per_cpu ksoftirqd pointer
instead, as suggested by Eric Dumazet.Tested-by: Shaun Ruffell
Signed-off-by: Venkatesh Pallipadi
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar
23 Jan, 2011
1 commit
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When initiating I/O on a multiqueue and multi-IRQ device, we may want
to select a queue for which the response will be handled on the same
or a nearby CPU. This requires a reverse-map of IRQ affinity. Add a
notification mechanism to support this.This is based closely on work by Thomas Gleixner .
Signed-off-by: Ben Hutchings
Cc: linux-net-drivers@solarflare.com
Cc: Tom Herbert
Cc: David Miller
LKML-Reference:
Signed-off-by: Thomas Gleixner
10 Nov, 2010
1 commit
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We currently use kmalloc-96 slab for struct irqaction allocations on
64bit arches.This is unfortunate because of possible false sharing and two cache
lines accesses.Move 'name' and 'dir' fields at the end of the structure, and force a
suitable alignement.Hot path fields now use one cache line on x86_64.
Signed-off-by: Eric Dumazet
Reviewed-by: Andi Kleen
Cc: Peter Zijlstra
LKML-Reference:
Signed-off-by: Thomas Gleixner
28 Oct, 2010
1 commit
-
…/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits)
perf python scripting: Add futex-contention script
perf python scripting: Fixup cut'n'paste error in sctop script
perf scripting: Shut up 'perf record' final status
perf record: Remove newline character from perror() argument
perf python scripting: Support fedora 11 (audit 1.7.17)
perf python scripting: Improve the syscalls-by-pid script
perf python scripting: print the syscall name on sctop
perf python scripting: Improve the syscalls-counts script
perf python scripting: Improve the failed-syscalls-by-pid script
kprobes: Remove redundant text_mutex lock in optimize
x86/oprofile: Fix uninitialized variable use in debug printk
tracing: Fix 'faild' -> 'failed' typo
perf probe: Fix format specified for Dwarf_Off parameter
perf trace: Fix detection of script extension
perf trace: Use $PERF_EXEC_PATH in canned report scripts
perf tools: Document event modifiers
perf tools: Remove direct slang.h include
perf_events: Fix for transaction recovery in group_sched_in()
perf_events: Revert: Fix transaction recovery in group_sched_in()
perf, x86: Use NUMA aware allocations for PEBS/BTS/DS allocations
...
24 Oct, 2010
1 commit
-
…inux-2.6 into perf/urgent
23 Oct, 2010
1 commit
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… 'x86-quirks-for-linus', 'x86-setup-for-linus', 'x86-uv-for-linus' and 'x86-vm86-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'softirq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
softirqs: Make wakeup_softirqd static* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, asm: Restore parentheses around one pushl_cfi argument
x86, asm: Fix ancient-GAS workaround
x86, asm: Fix CFI macro invocations to deal with shortcomings in gas* 'x86-numa-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, numa: Assign CPUs to nodes in round-robin manner on fake NUMA* 'x86-quirks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: HPET force enable for CX700 / VIA Epia LT* 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, setup: Use string copy operation to optimze copy in kernel compression* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, UV: Use allocated buffer in tlb_uv.c:tunables_read()* 'x86-vm86-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, vm86: Fix preemption bug for int1 debug and int3 breakpoint handlers.
22 Oct, 2010
1 commit
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* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (96 commits)
apic, x86: Use BIOS settings for IBS and MCE threshold interrupt LVT offsets
apic, x86: Check if EILVT APIC registers are available (AMD only)
x86: ioapic: Call free_irte only if interrupt remapping enabled
arm: Use ARCH_IRQ_INIT_FLAGS
genirq, ARM: Fix boot on ARM platforms
genirq: Fix CONFIG_GENIRQ_NO_DEPRECATED=y build
x86: Switch sparse_irq allocations to GFP_KERNEL
genirq: Switch sparse_irq allocator to GFP_KERNEL
genirq: Make sparse_lock a mutex
x86: lguest: Use new irq allocator
genirq: Remove the now unused sparse irq leftovers
genirq: Sanitize dynamic irq handling
genirq: Remove arch_init_chip_data()
x86: xen: Sanitise sparse_irq handling
x86: Use sane enumeration
x86: uv: Clean up the direct access to irq_desc
x86: Make io_apic.c local functions static
genirq: Remove irq_2_iommu
x86: Speed up the irq_remapped check in hot pathes
intr_remap: Simplify the code further
...Fix up trivial conflicts in arch/x86/Kconfig
21 Oct, 2010
1 commit
-
With the addition of trace_softirq_raise() the softirq tracepoint got
even more convoluted. Why the tracepoints take two pointers to assign
an integer is beyond my comprehension.But adding an extra case which treats the first pointer as an unsigned
long when the second pointer is NULL including the back and forth
type casting is just horrible.Convert the softirq tracepoints to take a single unsigned int argument
for the softirq vector number and fix the call sites.Signed-off-by: Thomas Gleixner
LKML-Reference:
Acked-by: Peter Zijlstra
Acked-by: mathieu.desnoyers@efficios.com
Cc: Frederic Weisbecker
Cc: Steven Rostedt
12 Oct, 2010
1 commit
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This function should have not been there in the first place.
Signed-off-by: Thomas Gleixner
Reviewed-by: Ingo Molnar
22 Sep, 2010
1 commit
-
No users outside of kernel/softirq.c
Signed-off-by: Thomas Gleixner
07 Sep, 2010
1 commit
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Add a tracepoint for tracing when softirq action is raised.
This and the existing tracepoints complete softirq's tracepoints:
softirq_raise, softirq_entry and softirq_exit.And when this tracepoint is used in combination with
the softirq_entry tracepoint we can determine
the softirq raise latency.Signed-off-by: Lai Jiangshan
Acked-by: Mathieu Desnoyers
Acked-by: Neil Horman
Cc: David Miller
Cc: Kaneshige Kenji
Cc: Izumo Taku
Cc: Kosaki Motohiro
Cc: Lai Jiangshan
Cc: Scott Mcmillan
Cc: Steven Rostedt
Cc: Eric Dumazet
LKML-Reference:
[ factorize softirq events with DECLARE_EVENT_CLASS ]
Signed-off-by: Koki Sanagi
Signed-off-by: Frederic Weisbecker
29 Jul, 2010
1 commit
-
A small number of users of IRQF_TIMER are using it for the implied no
suspend behaviour on interrupts which are not timer interrupts.Therefore add a new IRQF_NO_SUSPEND flag, rename IRQF_TIMER to
__IRQF_TIMER and redefine IRQF_TIMER in terms of these new flags.Signed-off-by: Ian Campbell
Cc: Jeremy Fitzhardinge
Cc: Dmitry Torokhov
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Grant Likely
Cc: xen-devel@lists.xensource.com
Cc: linux-input@vger.kernel.org
Cc: linuxppc-dev@ozlabs.org
Cc: devicetree-discuss@lists.ozlabs.org
LKML-Reference:
Signed-off-by: Thomas Gleixner
22 May, 2010
1 commit
-
Fix kernel-doc fatal error:
/** beginning a non-kernel-doc comment block:
(That alone does not kill kernel-doc, but the 'enum' was
totally confusing to it.)Error(/lnx/src/TMP/linux-2.6.34-git6//include/linux/interrupt.h:88): cannot understand prototype: 'enum '
make[2]: *** [Documentation/DocBook/genericirq.xml] Error 1Signed-off-by: Randy Dunlap
Signed-off-by: Linus Torvalds
03 May, 2010
1 commit
-
This patch adds a cpumask affinity hint to the irq_desc structure,
along with a registration function and a read-only proc entry for each
interrupt.This affinity_hint handle for each interrupt can be used by underlying
drivers that need a better mechanism to control interrupt affinity.
The underlying driver can register a cpumask for the interrupt, which
will allow the driver to provide the CPU mask for the interrupt to
anything that requests it. The intent is to extend the userspace
daemon, irqbalance, to help hint to it a preferred CPU mask to balance
the interrupt into.[ tglx: Fixed compile warnings, added WARN_ON, made SMP only ]
Signed-off-by: Peter P Waskiewicz Jr
Cc: davem@davemloft.net
Cc: arjan@linux.jf.intel.com
Cc: bhutchings@solarflare.com
LKML-Reference:
Signed-off-by: Thomas Gleixner
13 Apr, 2010
2 commits
-
Remove all code which is related to IRQF_DISABLED from the core kernel
code. IRQF_DISABLED still exists as a flag, but becomes a NOOP and
will be removed after a grace period. That way we can easily revert to
the previous behaviour by just restoring the core code.Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Alan Cox
Cc: Andi Kleen
Cc: David Miller
Cc: Greg Kroah-Hartman
Cc: Arnaldo Carvalho de Melo
Cc: Linus Torvalds
LKML-Reference: -
Now that we enjoy threaded interrupts, we're starting to see irq_chip
implementations (wm831x, pca953x) that make use of threaded interrupts
for the controller, and nested interrupts for the client interrupt. It
all works very well, with one drawback:Drivers requesting an IRQ must now know whether the handler will
run in a thread context or not, and call request_threaded_irq() or
request_irq() accordingly.The problem is that the requesting driver sometimes doesn't know
about the nature of the interrupt, specially when the interrupt
controller is a discrete chip (typically a GPIO expander connected
over I2C) that can be connected to a wide variety of otherwise perfectly
supported hardware.This patch introduces the request_any_context_irq() function that mostly
mimics the usual request_irq(), except that it checks whether the irq
level is configured as nested or not, and calls the right backend.
On success, it also returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.[ tglx: Made return value an enum, simplified code and made the export
of request_any_context_irq GPL ]Signed-off-by: Marc Zyngier
Cc:
LKML-Reference:
Signed-off-by: Thomas Gleixner
04 Nov, 2009
1 commit
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commit 74296a8ed added this function for debug purposes, but it was
never used for anything. Remove it.Signed-off-by: Thomas Gleixner
12 Oct, 2009
1 commit
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After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.Signed-off-by: Alexey Dobriyan
24 Sep, 2009
2 commits
-
By 7be23e278f, mask field was deleted by irqaction. However, it was not
deleted from comment.Signed-off-by: Nobuhiro Iwamatsu
CC: Rusty Russell
Signed-off-by: Rusty Russell -
Up until 1.1.83, the primitive human tribes used struct sigaction for
interrupts. The sa_mask field was overloaded to hold a pointer to the
name.When someone created the new "struct irqaction" they carried across
the "mask" field as a kind of ancestor worship: the fact that it was
unused makes clear its spiritual significance.Signed-off-by: Rusty Russell
15 Sep, 2009
1 commit
-
* 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block: (29 commits)
block: use blkdev_issue_discard in blk_ioctl_discard
Make DISCARD_BARRIER and DISCARD_NOBARRIER writes instead of reads
block: don't assume device has a request list backing in nr_requests store
block: Optimal I/O limit wrapper
cfq: choose a new next_req when a request is dispatched
Seperate read and write statistics of in_flight requests
aoe: end barrier bios with EOPNOTSUPP
block: trace bio queueing trial only when it occurs
block: enable rq CPU completion affinity by default
cfq: fix the log message after dispatched a request
block: use printk_once
cciss: memory leak in cciss_init_one()
splice: update mtime and atime on files
block: make blk_iopoll_prep_sched() follow normal 0/1 return convention
cfq-iosched: get rid of must_alloc flag
block: use interrupts disabled version of raise_softirq_irqoff()
block: fix comment in blk-iopoll.c
block: adjust default budget for blk-iopoll
block: fix long lines in block/blk-iopoll.c
block: add blk-iopoll, a NAPI like approach for block devices
...
11 Sep, 2009
1 commit
-
This borrows some code from NAPI and implements a polled completion
mode for block devices. The idea is the same as NAPI - instead of
doing the command completion when the irq occurs, schedule a dedicated
softirq in the hopes that we will complete more IO when the iopoll
handler is invoked. Devices have a budget of commands assigned, and will
stay in polled mode as long as they continue to consume their budget
from the iopoll softirq handler. If they do not, the device is set back
to interrupt completion mode.This patch holds the core bits for blk-iopoll, device driver support
sold separately.Signed-off-by: Jens Axboe
