For a very high speed DMA various periphral devices need
scatter-gather list support. The DMA hardware support link list items.
This list can be circular also (adding new flag DMA_PREP_CIRCULAR_LIST)
Right now this flag is in driver header and should be moved to
dmaengine header file eventually
Signed-off-by: Ramesh Babu K V <ramesh.b.k.v@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that the generic DMAEngine API has support for scatterlist to
scatterlist copying, the device_prep_slave_sg() portion of the
DMA_SLAVE API is no longer necessary and has been removed.
However, the device_control() portion of the DMA_SLAVE API is still
useful to control device specific parameters, such as externally
controlled DMA transfers and maximum burst length.
A special dma_ctrl_cmd has been added to enable externally controlled
DMA transfers. This is currently specific to the Freescale DMA
controller, but can easily be made generic when another user is found.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This adds support for scatterlist to scatterlist DMA transfers. A
similar interface is exposed by the fsldma driver (through the DMA_SLAVE
API) and by the ste_dma40 driver (through an exported function).
This patch paves the way for making this type of copy operation a part
of the generic DMAEngine API. Futher patches will add support in
individual drivers.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fix the IRQ flag handling naming. In linux/irqflags.h under one configuration,
it maps:
local_irq_enable() -> raw_local_irq_enable()
local_irq_disable() -> raw_local_irq_disable()
local_irq_save() -> raw_local_irq_save()
...
and under the other configuration, it maps:
raw_local_irq_enable() -> local_irq_enable()
raw_local_irq_disable() -> local_irq_disable()
raw_local_irq_save() -> local_irq_save()
...
This is quite confusing. There should be one set of names expected of the
arch, and this should be wrapped to give another set of names that are expected
by users of this facility.
Change this to have the arch provide:
flags = arch_local_save_flags()
flags = arch_local_irq_save()
arch_local_irq_restore(flags)
arch_local_irq_disable()
arch_local_irq_enable()
arch_irqs_disabled_flags(flags)
arch_irqs_disabled()
arch_safe_halt()
Then linux/irqflags.h wraps these to provide:
raw_local_save_flags(flags)
raw_local_irq_save(flags)
raw_local_irq_restore(flags)
raw_local_irq_disable()
raw_local_irq_enable()
raw_irqs_disabled_flags(flags)
raw_irqs_disabled()
raw_safe_halt()
with type checking on the flags 'arguments', and then wraps those to provide:
local_save_flags(flags)
local_irq_save(flags)
local_irq_restore(flags)
local_irq_disable()
local_irq_enable()
irqs_disabled_flags(flags)
irqs_disabled()
safe_halt()
with tracing included if enabled.
The arch functions can now all be inline functions rather than some of them
having to be macros.
Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300]
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile]
Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze]
Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM]
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR]
Acked-by: Tony Luck <tony.luck@intel.com> [IA-64]
Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R]
Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS]
Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC]
Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC]
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390]
Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score]
Acked-by: Matt Fleming <matt@console-pimps.org> [SH]
Acked-by: David S. Miller <davem@davemloft.net> [Sparc]
Acked-by: Chris Zankel <chris@zankel.net> [Xtensa]
Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha]
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300]
Cc: starvik@axis.com [CRIS]
Cc: jesper.nilsson@axis.com [CRIS]
Cc: linux-cris-kernel@axis.com
Drop inclusions of asm/system.h from linux/hardirq.h and linux/list.h as
they're no longer required and prevent the M68K arch's IRQ flag handling macros
from being made into inlined functions due to circular dependencies.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2.6.36 introduces an API for drivers to switch the IO scheduler
instead of manually calling the elevator exit and init functions.
This API was added since q->elevator must be cleared in between
those two calls. And since we already have this functionality
directly from use by the sysfs interface to switch schedulers
online, it was prudent to reuse it internally too.
But this API needs the queue to be in a fully initialized state
before it is called, or it will attempt to unregister elevator
kobjects before they have been added. This results in an oops
like this:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000051
IP: [<ffffffff8116f15e>] sysfs_create_dir+0x2e/0xc0
PGD 47ddfc067 PUD 47c6a1067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:02.0/0000:04:00.1/irq
CPU 2
Modules linked in: t(+) loop hid_apple usbhid ahci ehci_hcd uhci_hcd libahci usbcore nls_base igb
Pid: 7319, comm: modprobe Not tainted 2.6.36-rc6+ #132 QSSC-S4R/QSSC-S4R
RIP: 0010:[<ffffffff8116f15e>] [<ffffffff8116f15e>] sysfs_create_dir+0x2e/0xc0
RSP: 0018:ffff88027da25d08 EFLAGS: 00010246
RAX: ffff88047c68c528 RBX: 00000000fffffffe RCX: 0000000000000000
RDX: 000000000000002f RSI: 000000000000002f RDI: ffff88047e196c88
RBP: ffff88027da25d38 R08: 0000000000000000 R09: d84156c5635688c0
R10: d84156c5635688c0 R11: 0000000000000000 R12: ffff88047e196c88
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88047c68c528
FS: 00007fcb0b26f6e0(0000) GS:ffff880287400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000051 CR3: 000000047e76e000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process modprobe (pid: 7319, threadinfo ffff88027da24000, task ffff88027d377090)
Stack:
ffff88027da25d58 ffff88047c68c528 00000000fffffffe ffff88047e196c88
<0> ffff88047c68c528 ffff88047e05bd90 ffff88027da25d78 ffffffff8123fb77
<0> ffff88047e05bd90 0000000000000000 ffff88047e196c88 ffff88047c68c528
Call Trace:
[<ffffffff8123fb77>] kobject_add_internal+0xe7/0x1f0
[<ffffffff8123fd98>] kobject_add_varg+0x38/0x60
[<ffffffff8123feb9>] kobject_add+0x69/0x90
[<ffffffff8116efe0>] ? sysfs_remove_dir+0x20/0xa0
[<ffffffff8103d48d>] ? sub_preempt_count+0x9d/0xe0
[<ffffffff8143de20>] ? _raw_spin_unlock+0x30/0x50
[<ffffffff8116efe0>] ? sysfs_remove_dir+0x20/0xa0
[<ffffffff8116eff4>] ? sysfs_remove_dir+0x34/0xa0
[<ffffffff81224204>] elv_register_queue+0x34/0xa0
[<ffffffff81224aad>] elevator_change+0xfd/0x250
[<ffffffffa007e000>] ? t_init+0x0/0x361 [t]
[<ffffffffa007e000>] ? t_init+0x0/0x361 [t]
[<ffffffffa007e0a8>] t_init+0xa8/0x361 [t]
[<ffffffff810001de>] do_one_initcall+0x3e/0x170
[<ffffffff8108c3fd>] sys_init_module+0xbd/0x220
[<ffffffff81002f2b>] system_call_fastpath+0x16/0x1b
Code: e5 41 56 41 55 41 54 49 89 fc 53 48 83 ec 10 48 85 ff 74 52 48 8b 47 18 49 c7 c5 00 46 61 81 48 85 c0 74 04 4c 8b 68 30 45 31 f6 <41> 80 7d 51 00 74 0e 49 8b 44 24 28 4c 89 e7 ff 50 20 49 89 c6
RIP [<ffffffff8116f15e>] sysfs_create_dir+0x2e/0xc0
RSP <ffff88027da25d08>
CR2: 0000000000000051
---[ end trace a6541d3bf07945df ]---
Fix this by adding a registered bit to the elevator queue, which is
set when the sysfs kobjects have been registered.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This information is already available in mac80211, we just need to export it
via cfg80211 and nl80211.
Signed-off-by: Bruno Randolf <br1@einfach.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This adds API to allow adding per-station GTKs,
updates mac80211 to support it, and also allows
drivers to remove a key from hwaccel again when
this may be necessary due to multiple GTKs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Currently disabling CONFIG_SLUB_DEBUG also disabled SYSFS support meaning
that the slabs cannot be tuned without DEBUG.
Make SYSFS support independent of CONFIG_SLUB_DEBUG
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
USB only gives the maximum current allowed to draw.
Signed-off-by: Heikki Krogerus <ext-heikki.krogerus@nokia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
This adds power supply types for USB chargers defined in
Battery Charging Specification 1.1.
Signed-off-by: Heikki Krogerus <ext-heikki.krogerus@nokia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Allow sysadmins to configure the number of multicast
membership report sent on a link failure event.
Signed-off-by: Flavio Leitner <fleitner@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add wrapper functions around the dma_device->device_control function
to bring back type safety. Also, add a wrapper function around
dma_async_tx_descriptor->tx_submit. This is named dmaengine_submit
instead of dmaengine_tx_submit to get rid of the confusing 'tx' in the
function name
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cyclic transfers are useful for audio where a single buffer divided
in periods has to be transfered endlessly until stopped. After being
prepared the transfer is started using the dma_async_descriptor->tx_submit
function. dma_async_descriptor->callback is called after each period.
The transfer is stopped using the DMA_TERMINATE_ALL callback.
While being used for cyclic transfers the channel cannot be used
for other transfer types.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In various situations, a device provides a packet to our stack and we
drop it before it enters protocol stack :
- softnet backlog full (accounted in /proc/net/softnet_stat)
- bad vlan tag (not accounted)
- unknown/unregistered protocol (not accounted)
We can handle a per-device counter of such dropped frames at core level,
and automatically adds it to the device provided stats (rx_dropped), so
that standard tools can be used (ifconfig, ip link, cat /proc/net/dev)
This is a generalization of commit 8990f468a (net: rx_dropped
accounting), thus reverting it.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As suggested by Linus, push the irqs_disabled() down to the
rcu_read_lock_bh_held() level so that all callers get the benefit
of the correct check.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Move the header to a standard linux device driver location.
This should pave the way for other drivers to be moved into the relevant
directories.
ti_wilink_st.h is a common header file used by the TI's shared transport device
driver for WiLink chipsets. Each individual protocol drivers like bluetooth
driver, FM V4L2 driver and GPS drivers will make use of this header.
Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Texas Instrument's WiLink7 connectivity devices pack wireless connectivity
technologies like Bluetooth, FM Radio Receiver and Transmitter, GPS and WLAN
into a single die.
The BT, FM and GPS core on the chip are interfaced to application
processors via a single UART.
This line discipline driver allows such different technologies to be used
simultaneous and independent of each other.
Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The "flags" member of "struct wait_queue_t" is used in several places in
the kernel code without beeing initialized by init_wait(). "flags" is
used in bitwise operations.
If "flags" not initialized then unexpected behaviour may take place.
Incorrect flags might used later in code.
Added initialization of "wait_queue_t.flags" with zero value into
"init_wait".
Signed-off-by: Evgeny Kuznetsov <EXT-Eugeny.Kuznetsov@nokia.com>
[ The bit we care about does end up being initialized by both
prepare_to_wait() and add_to_wait_queue(), so this doesn't seem to
cause actual bugs, but is definitely the right thing to do -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible to do most of the module loading in parallel.
However, that whole conversion totally missed the rather obscure code
that adds a new module to the list for BUG() handling. That code was
doubly obscure because (a) the code itself lives in lib/bugs.c (for
dubious reasons) and (b) it gets called from the architecture-specific
"module_finalize()" rather than from generic code.
Calling it from arch-specific code makes no sense what-so-ever to begin
with, and is now actively wrong since that code isn't protected by the
module loading lock any more.
So this commit moves the "module_bug_{finalize,cleanup}()" calls away
from the arch-specific code, and into the generic code - and in the
process protects it with the module_mutex so that the list operations
are now safe.
Future fixups:
- move the module list handling code into kernel/module.c where it
belongs.
- get rid of 'module_bug_list' and just use the regular list of modules
(called 'modules' - imagine that) that we already create and maintain
for other reasons.
Reported-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Adrian Bunk <bunk@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The documentation for NL80211_CMD_REMAIN_ON_CHANNEL
isn't accurate, an interface index is required by
the command. Update it accordingly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Added a nl interface to set the peer bssid of a WDS interface.
Signed-off-by: Bill Jordan <bjordan@rajant.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Some user space applications only want to display survey data for
the operating channel, however there is no API to get that yet.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
smbfs has been scheduled for removal in 2.6.27, so
maybe we can now move it to drivers/staging on the
way out.
smbfs still uses the big kernel lock and nobody
is going to fix that, so we should be getting
rid of it soon.
This removes the 32 bit compat mount and ioctl
handling code, which is implemented in common fs
code, and moves all smbfs related files into
drivers/staging/smbfs.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This splits up the sh intc core in to something more vaguely resembling
a subsystem. Most of the functionality was alread fairly well
compartmentalized, and there were only a handful of interdependencies
that needed to be resolved in the process.
This also serves as future-proofing for the genirq and sparseirq rework,
which will make some of the split out functionality wholly generic,
allowing things to be killed off in place with minimal migration pain.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
If lookups happen while the radix node still points to a subgroup
mapping, an IRQ hasn't yet been made available for the specified id, so
error out accordingly. Once the slot is replaced with an IRQ mapping and
the tag is discarded, lookup can commence as normal.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This prepares the removal of the big kernel lock from the
file locking code. We still use the BKL as long as fs/lockd
uses it and ceph might sleep, but we can flip the definition
to a private spinlock as soon as that's done.
All users outside of fs/lockd get converted to use
lock_flocks() instead of lock_kernel() where appropriate.
Based on an earlier patch to use a spinlock from Matthew
Wilcox, who has attempted this a few times before, the
earliest patch from over 10 years ago turned it into
a semaphore, which ended up being slower than the BKL
and was subsequently reverted.
Someone should do some serious performance testing when
this becomes a spinlock, since this has caused problems
before. Using a spinlock should be at least as good
as the BKL in theory, but who knows...
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
rtnl_dereference() is used in contexts where RTNL is held, to fetch an
RCU protected pointer.
Updates to this pointer are prevented by RTNL, so we dont need
smp_read_barrier_depends() and the ACCESS_ONCE() provided in
rcu_dereference_check().
rtnl_dereference() is mainly a macro to document the locking invariant.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ingress being not used very much, and net_device->ingress_queue being
quite a big object (128 or 256 bytes), use a dynamic allocation if
needed (tc qdisc add dev eth0 ingress ...)
dev_ingress_queue(dev) helper should be used only with RTNL taken.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many interrupts that share a single mask source but are on different
hardware vectors will have an associated register tied to an INTEVT that
denotes the precise cause for the interrupt exception being triggered.
This introduces the concept of IRQ subgroups in the intc core, where
a virtual IRQ map is constructed for each of the pre-defined cause bits,
and a higher level chained handler takes control of the parent INTEVT.
This enables CPUs with heavily muxed IRQ vectors (especially across
disjoint blocks) to break things out in to a series of managed chained
handlers while being able to dynamically lookup and adopt the IRQs
created for them.
This is largely an opt-in interface, requiring CPUs to manually submit
IRQs for subgroup splitting, in addition to providing identifiers in
their enum maps that can be used for lazy lookup via the radix tree.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Dozen of changes in ncpfs to provide some locking other than BKL.
In readdir cache unlock and mark complete first page as last operation,
so it can be used for synchronization, as code intended.
When updating dentry name on case insensitive filesystems do at least
some basic locking...
Hold i_mutex when updating inode fields.
Push some ncp_conn_is_valid down to ncp_request. Connection can become
invalid at any moment, and fewer error code paths to test the better.
Use i_size_{read,write} to modify file size.
Set inode's backing_dev_info as ncpfs has its own special bdi.
In ioctl unbreak ioctls invoked on filesystem mounted 'ro' - tests are
for inode writeable or owner match, but were turned to filesystem
writeable and inode writeable or owner match. Also collect all permission
checks in single place.
Add some locking, and remove comments saying that it would be cool to
add some locks to the code.
Constify some pointers.
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This implements a scheme roughly analogous to the PowerPC virtual to
hardware IRQ mapping, which we use for IRQ to per-controller ID mapping.
This makes it possible for drivers to use the IDs directly for lookup
instead of hardcoding the vector.
The main motivation for this work is as a building block for dynamically
allocating virtual IRQs for demuxing INTC events sharing a single INTEVT
in addition to a common masking source.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Allow the persistence engine of a virtual service to be set, edited
and unset.
This feature only works with the netlink user-space interface.
Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Julian Anastasov <ja@ssi.bg>
This option covers now the old chip functions and the irq_desc data
fields which are moving to struct irq_data. More stuff will follow.
Pretty handy for testing a conversion, whether something broke or not.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
The low level irq chip functions want access to irq_desc->irq_data.
Provide new functions which hand down irq_data instead of the irq
number so these functions avoid to call irq_to_desc() which is a radix
tree lookup in case of sparse irq.
This provides all the old functions except one: end(). end() is a
relict of __do_IRQ() and will just go away with the __do_IRQ() code.
The replacement for set_affinity() has an extra argument "bool
force". The reason for this is to notify the low level code, that the
move has to be done right away and cannot be delayed until the next
interrupt happens. That's necessary to handle the irq fixup on cpu
unplug in the generic code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20100927121841.742126604@linutronix.de>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Convert all references in the core code to orq, chip, handler_data,
chip_data, msi_desc, affinity to irq_data.*
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Low level chip functions need access to irq_desc->handler_data,
irq_desc->chip_data and irq_desc->msi_desc. We hand down the irq
number to the low level functions, so they need to lookup irq_desc.
With sparse irq this means a radix tree lookup.
We could hand down irq_desc itself, but low level chip functions have
no need to fiddle with it directly and we want to restrict access to
irq_desc further.
Preparatory patch for new chip functions.
Note, that the ugly anon union/struct is there to avoid a full tree
wide clean up for now. This is not going to last 3 years like __do_IRQ()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20100927121841.645542300@linutronix.de>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Use RCU & RTNL protection for mfc_cache_array[]
ipmr_cache_find() is called under rcu_read_lock();
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Presently the pinmux code is a one-way thing, but there's nothing
preventing an unregistration if no one has grabbed any of the pins.
This will permit us to save a bit of memory on systems that require pin
demux for certain peripherals in the case where registration of those
peripherals fails, or they are otherwise not attached to the system.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Some controllers will need to be initialized lazily due to pinmux
constraints, while others may simply have no need to be brought online if
there are no backing devices for them attached. In this case it's still
necessary to be able to reserve their hardware vector map before dynamic
IRQs get a hold of them.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Reduce the #ifdefs and simplify bootstrap by making SMP and NUMA as much alike
as possible. This means that there will be an additional indirection to get to
the kmem_cache_node field under SMP.
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
On UP, percpu allocations were redirected to kmalloc. This has the
following problems.
* For certain amount of allocations (determined by
PERCPU_DYNAMIC_EARLY_SLOTS and PERCPU_DYNAMIC_EARLY_SIZE), percpu
allocator can be used before the usual kernel memory allocator is
brought online. On SMP, this is used to initialize the kernel
memory allocator.
* percpu allocator honors alignment upto PAGE_SIZE but kmalloc()
doesn't. For example, workqueue makes use of larger alignments for
cpu_workqueues.
Currently, users of percpu allocators need to handle UP differently,
which is somewhat fragile and ugly. Other than small amount of
memory, there isn't much to lose by enabling percpu allocator on UP.
It can simply use kernel memory based chunk allocation which was added
for SMP archs w/o MMUs.
This patch removes mm/percpu_up.c, builds mm/percpu.c on UP too and
makes UP build use percpu-km. As percpu addresses and kernel
addresses are always identity mapped and static percpu variables don't
need any special treatment, nothing is arch dependent and mm/percpu.c
implements generic setup_per_cpu_areas() for UP.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
