barrier: Reduce the amount of disturbance by rcu_barrier() to the rest of
the system. This branch also includes improvements to
RCU_FAST_NO_HZ, which are included here due to conflicts.
fixes: Miscellaneous fixes.
inline: Remaining changes from an abortive attempt to inline
preemptible RCU's __rcu_read_lock(). These are (1) making
exit_rcu() avoid unnecessary work and (2) avoiding having
preemptible RCU record a blocked thread when the scheduler
declines to do a context switch.
srcu: Lai Jiangshan's algorithmic implementation of SRCU, including
call_srcu().
When running preemptible RCU, if a task exits in an RCU read-side
critical section having blocked within that same RCU read-side critical
section, the task must be removed from the list of tasks blocking a
grace period (perhaps the current grace period, perhaps the next grace
period, depending on timing). The exit() path invokes exit_rcu() to
do this cleanup.
However, the current implementation of exit_rcu() needlessly does the
cleanup even if the task did not block within the current RCU read-side
critical section, which wastes time and needlessly increases the size
of the state space. Fix this by only doing the cleanup if the current
task is actually on the list of tasks blocking some grace period.
While we are at it, consolidate the two identical exit_rcu() functions
into a single function.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts:
kernel/rcupdate.c
Currently, PREEMPT_RCU readers are enqueued upon entry to the scheduler.
This is inefficient because enqueuing is required only if there is a
context switch, and entry to the scheduler does not guarantee a context
switch.
The commit therefore moves the enqueuing to immediately precede the
call to switch_to() from the scheduler.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit implements an SRCU state machine in support of call_srcu().
The state machine is preemptible, light-weight, and single-threaded,
minimizing synchronization overhead. In particular, there is no longer
any need for synchronize_srcu() to be guarded by a mutex.
Expedited processing is handled, at least in the absence of concurrent
grace-period operations on that same srcu_struct structure, by having
the synchronize_srcu_expedited() thread take on the role of the
workqueue thread for one iteration.
There is a reasonable probability that a given SRCU callback will
be invoked on the same CPU that registered it, however, there is no
guarantee. Concurrent SRCU grace-period primitives can cause callbacks
to be executed elsewhere, even in absence of CPU-hotplug operations.
Callbacks execute in process context, but under the influence of
local_bh_disable(), so it is illegal to sleep in an SRCU callback
function.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The old srcu_barrier() macro is now unused. This commit removes it so
that it may be used for the SRCU flavor of rcu_barrier(), which will in
turn be needed to allow the upcoming call_srcu() to be used from within
modules.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit implements a variant of Peter's algorithm, which may be found
at https://lkml.org/lkml/2012/2/1/119.
o Make the checking lock-free to enable parallel checking.
Parallel checking is required when (1) the original checking
task is preempted for a long time, (2) sychronize_srcu_expedited()
starts during an ongoing SRCU grace period, or (3) we wish to
avoid acquiring a lock.
o Since the checking is lock-free, we avoid a mutex in state machine
for call_srcu().
o Remove the SRCU_REF_MASK and remove the coupling with the flipping.
This might allow us to remove the preempt_disable() in future
versions, though such removal will need great care because it
rescinds the one-old-reader-per-CPU guarantee.
o Remove a smp_mb(), simplify the comments and make the smp_mb() pairs
more intuitive.
Inspired-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The purpose of the upper bit of SRCU's per-CPU counters is to guarantee
that no reasonable series of srcu_read_lock() and srcu_read_unlock()
operations can return the value of the counter to its original value.
This guarantee is require only after the index has been switched to
the other set of counters, so at most one srcu_read_lock() can affect
a given CPU's counter. The number of srcu_read_unlock() operations
on a given counter is limited to the number of tasks in the system,
which given the Linux kernel's current structure is limited to far less
than 2^30 on 32-bit systems and far less than 2^62 on 64-bit systems.
(Something about a limited number of bytes in the kernel's address space.)
Therefore, if srcu_read_lock() increments the upper bits, then
srcu_read_unlock() need not do so. In this case, an srcu_read_lock() and
an srcu_read_unlock() will flip the lower bit of the upper field of the
counter. An unreasonably large additional number of srcu_read_unlock()
operations would be required to return the counter to its initial value,
thus preserving the guarantee.
This commit takes this approach, which further allows it to shrink
the size of the upper field to one bit, making the number of
srcu_read_unlock() operations required to return the counter to its
initial value even more unreasonable than before.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current implementation of synchronize_srcu_expedited() can cause
severe OS jitter due to its use of synchronize_sched(), which in turn
invokes try_stop_cpus(), which causes each CPU to be sent an IPI.
This can result in severe performance degradation for real-time workloads
and especially for short-interation-length HPC workloads. Furthermore,
because only one instance of try_stop_cpus() can be making forward progress
at a given time, only one instance of synchronize_srcu_expedited() can
make forward progress at a time, even if they are all operating on
distinct srcu_struct structures.
This commit, inspired by an earlier implementation by Peter Zijlstra
(https://lkml.org/lkml/2012/1/31/211) and by further offline discussions,
takes a strictly algorithmic bits-in-memory approach. This has the
disadvantage of requiring one explicit memory-barrier instruction in
each of srcu_read_lock() and srcu_read_unlock(), but on the other hand
completely dispenses with OS jitter and furthermore allows SRCU to be
used freely by CPUs that RCU believes to be idle or offline.
The update-side implementation handles the single read-side memory
barrier by rechecking the per-CPU counters after summing them and
by running through the update-side state machine twice.
This implementation has passed moderate rcutorture testing on both
x86 and Power. Also updated to use this_cpu_ptr() instead of per_cpu_ptr(),
as suggested by Peter Zijlstra.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
The rcu_blocking_is_gp() function tests to see if there is only one
online CPU, and if so, synchronize_sched() and friends become no-ops.
However, for larger systems, num_online_cpus() scans a large vector,
and might be preempted while doing so. While preempted, any number
of CPUs might come online and go offline, potentially resulting in
num_online_cpus() returning 1 when there never had only been one
CPU online. This could result in a too-short RCU grace period, which
could in turn result in total failure, except that the only way that
the grace period is too short is if there is an RCU read-side critical
section spanning it. For RCU-sched and RCU-bh (which are the only
cases using rcu_blocking_is_gp()), RCU read-side critical sections
have either preemption or bh disabled, which prevents CPUs from going
offline. This in turn prevents actual failures from occurring.
This commit therefore adds a large block comment to rcu_blocking_is_gp()
documenting why it is safe. This commit also moves rcu_blocking_is_gp()
into kernel/rcutree.c, which should help prevent unwary developers from
mistaking it for a generally useful function.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, __kfree_rcu() is implemented as an inline function, and
contains a BUILD_BUG_ON() that malfunctions if __kfree_rcu() is compiled
as an out-of-line function. Unfortunately, there are compiler settings
(e.g., -O0) that can result in __kfree_rcu() being compiled out of line,
resulting in annoying build breakage. This commit therefore converts
both __kfree_rcu() and __is_kfree_rcu_offset() from inline functions to
macros to prevent such misbehavior on the part of the compiler.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The list_first_entry_rcu() macro is inherently unsafe because it cannot
be applied to an empty list. But because RCU readers do not exclude
updaters, a list might become empty between the time that list_empty()
claimed it was non-empty and the time that list_first_entry_rcu() is
invoked. Therefore, the list_empty() test cannot be separated from the
list_first_entry_rcu() call. This commit therefore combines these to
macros to create a new list_first_or_null_rcu() macro that replaces
the old (and unsafe) list_first_entry_rcu() macro.
This patch incorporates Paul's review comments on the previous version of
this patch available here:
https://lkml.org/lkml/2012/4/2/536
This patch cannot break any upstream code because list_first_entry_rcu()
is not being used anywhere in the kernel (tested with grep(1)), and any
external code using it is probably broken as a result of using it.
Signed-off-by: Michel Machado <michel@digirati.com.br>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* Make __list_add_rcu check the next->prev and prev->next pointers
just like __list_add does.
* Make list_del_rcu use __list_del_entry, which does the same checking
at deletion time.
Has been running for a week here without anything being tripped up,
but it seems worth adding for completeness just in case something
ever does corrupt those lists.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Pull MMC fixes from Chris Ball:
- Build fix for omap_hsmmc with OF against 3.4-rc1.
- Fix CONFIG_MMC_UNSAFE_RESUME semantics regression against 3.3, which
broke hotplug card detection when UNSAFE_RESUME is set.
- Fix a race condition in omap_hsmmc with runtime PM.
- Fix two libertas SDIO-powered-resume regressions.
- Small fixes for discard/sanitize, dw_mmc, cd-gpio and esdhc-imx.
* tag 'mmc-fixes-for-3.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
mmc: core: Do not pre-claim host in suspend
mmc: dw_mmc: prevent NULL dereference for dma_ops
mmc: unbreak sdhci-esdhc-imx on i.MX25
mmc: cd-gpio: Include header to pickup exported symbol prototypes
mmc: sdhci: refine non-removable card checking for card detection
mmc: dw_mmc: Fix switch from DMA to PIO
mmc: remove MMC bus legacy suspend/resume method
mmc: omap_hsmmc: Get rid of of_have_populated_dt() usage
mmc: omap_hsmmc: build fix for CONFIG_OF=y and CONFIG_MMC_OMAP_HS=m
mmc: fixes for eMMC v4.5 sanitize operation
mmc: fixes for eMMC v4.5 discard operation
Pull MFD fixes from Samuel Ortiz:
"We have 3 build fixes, a OMAP USB host PHY reset fix and the twl6040
conversion to an i2c driver. The latter may not sound like a fix but
the twl6040 MFD driver won't probe without it, triggering an OMAP4
audio regression."
* tag 'mfd-for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
mfd: Fix modular builds of rc5t583 regulator support
mfd: Fix asic3_gpio_to_irq
ARM: OMAP3: USB: Fix the EHCI ULPI PHY reset issue
mfd: Convert twl6040 to i2c driver, and separate it from twl core
mfd : Fix dbx500 compilation error
This continues the theme started with vm_brk() and vm_munmap():
vm_mmap() does the same thing as do_mmap(), but additionally does the
required VM locking.
This uninlines (and rewrites it to be clearer) do_mmap(), which sadly
duplicates it in mm/mmap.c and mm/nommu.c. But that way we don't have
to export our internal do_mmap_pgoff() function.
Some day we hopefully don't have to export do_mmap() either, if all
modular users can become the simpler vm_mmap() instead. We're actually
very close to that already, with the notable exception of the (broken)
use in i810, and a couple of stragglers in binfmt_elf.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Like the vm_brk() function, this is the same as "do_munmap()", except it
does the VM locking for the caller.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It does the same thing as "do_brk()", except it handles the VM locking
too.
It turns out that all external callers want that anyway, so we can make
do_brk() static to just mm/mmap.c while at it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull pinctrl fixes from Linus Walleij:
- Fixed compilation errors and warnings
- Stricter checks on the ops vtable
* tag 'for-torvalds-20120418' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: implement pinctrl_check_ops
pinctrl: include <linux/bug.h> to prevent compile errors
pinctrl: fix compile error if not select PINMUX support
Pull USB fixes from Greg Kroah-Hartman:
"Here are a number of tiny USB fixes for 3.4-rc4.
Most of them are in the USB gadget area, but a few other minor USB
driver and core fixes are here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'usb-3.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (36 commits)
USB: serial: cp210x: Fixed usb_control_msg timeout values
USB: ehci-tegra: don't call set_irq_flags(IRQF_VALID)
USB: yurex: Fix missing URB_NO_TRANSFER_DMA_MAP flag in urb
USB: yurex: Remove allocation of coherent buffer for setup-packet buffer
drivers/usb/misc/usbtest.c: add kfrees
USB: ehci-fsl: Fix kernel crash on mpc5121e
uwb: fix error handling
uwb: fix use of del_timer_sync() in interrupt
EHCI: always clear the STS_FLR status bit
EHCI: fix criterion for resuming the root hub
USB: sierra: avoid QMI/wwan interface on MC77xx
usb: usbtest: avoid integer overflow in alloc_sglist()
usb: usbtest: avoid integer overflow in test_ctrl_queue()
USB: fix deadlock in bConfigurationValue attribute method
usb: gadget: eliminate NULL pointer dereference (bugfix)
usb: gadget: uvc: Remove non-required locking from 'uvc_queue_next_buffer' routine
usb: gadget: rndis: fix Missing req->context assignment
usb: musb: omap: fix the error check for pm_runtime_get_sync
usb: gadget: udc-core: fix asymmetric calls in remove_driver
usb: musb: omap: fix crash when musb glue (omap) gets initialized
...
Pull nfsd bugfixes from J. Bruce Fields:
"One bugfix, and one minor header fix from Jeff Layton while we're
here"
* 'for-3.4' of git://linux-nfs.org/~bfields/linux:
nfsd: include cld.h in the headers_install target
nfsd: don't fail unchecked creates of non-special files
Pull KVM updates from Marcelo Tosatti.
* git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: lock slots_lock around device assignment
KVM: VMX: Fix kvm_set_shared_msr() called in preemptible context
KVM: unmap pages from the iommu when slots are removed
KVM: PMU emulation: GLOBAL_CTRL MSR should be enabled on reset
Pull fuse updates from Miklos Szeredi.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: use flexible array in fuse.h
fuse: allow nanosecond granularity
fuse: O_DIRECT support for files
fuse: fix nlink after unlink
The combination of commit 1b1247dd75
"mfd: Add support for RICOH PMIC RC5T583"
and commit 6ffc327021
"regulator: Add support for RICOH PMIC RC5T583 regulator"
are causing the i386 allmodconfig builds to fail with this:
ERROR: "rc5t583_update" [drivers/regulator/rc5t583-regulator.ko] undefined!
ERROR: "rc5t583_set_bits" [drivers/regulator/rc5t583-regulator.ko] undefined!
ERROR: "rc5t583_clear_bits" [drivers/regulator/rc5t583-regulator.ko] undefined!
ERROR: "rc5t583_read" [drivers/regulator/rc5t583-regulator.ko] undefined!
and this:
ERROR: "rc5t583_ext_power_req_config" [drivers/regulator/rc5t583-regulator.ko] undefined!
For the 1st four, make the simple ops static inline, instead of
polluting the namespace with trivial exports. For the last one,
add an EXPORT_SYMBOL.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The cld.h file contains the definition of the upcall format to talk
with nfsdcld. When I added the file though, I neglected to add it
to the headers-y target, so make headers_install wasn't installing it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
usb: fixes for v3.4-rc cycle
Here are the fixes I have queued for v3.4-rc cycle so far.
It includes fixes on many of the gadget drivers and a few
of the UDC controller drivers.
For musb we have a fix for a kernel oops when unloading
omap2430.ko glue layer, proper error checking for pm_runtime_*,
fix for the ULPI transfer block, and a bug fix in musb_cleanup_urb
routine.
For s3c-hsotg we have mostly FIFO-related fixes (proper TX FIFO
allocation, TX FIFO corruption fix in DMA mode) but also a couple
of minor fixes (fixing maximum packet size for ep0 and fix for
big transfers with DMA).
For the dwc3 driver we have a memory leak fix, a very important
fix for USB30CV with SetFeature tests and the hability to handle
ep0 requests bigger than wMaxPacketSize.
On top of that there's a bunch of gadget driver minor fixes adding
proper section annotations, and fixing up the sysfs interface for
doing device-initiated connect/disconnect and so on.
All patches have been pending on the mailing list for quite a while
and look good for your for-linus branch.
Complete the separation of the twl6040 from the twl core since
it is a separate chip, not part of the twl6030 PMIC.
Make the needed Kconfig changes for the depending drivers at the
same time to avoid breaking the kernel build (vibra, ASoC components).
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonicro.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The ux500 default config enables the db5500 and the db8500.
The incoming cpuidle driver uses the 'prcmu_enable_wakeups'
and the 'prcmu_set_power_state' functions but these ones
are defined but not implemented for the db5500, leading to
an unresolved symbol error at link time. In order to compile,
we have to disable the db5500 support which is not acceptable
for the default config.
I noticed there are also some other functions which are
defined but not implemented.
This patch fix this by removing the functions definitions
and move out of the config section the empty functions which
are normally used when the DB550 config is disabled.
Only the functions which are not implemented are concerned
by this modification.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Pull ARM fixes from Russell King:
"Nothing too disasterous, the biggest thing being the removal of the
regulator support for vcore in the AMBA driver; only one SoC was using
this and it got broken during the last merge window, which then
started causing problems for other people. Mutual agreement was
reached for it to be removed."
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7386/1: jump_label: fixup for rename to static_key
ARM: 7384/1: ThumbEE: Disable userspace TEEHBR access for !CONFIG_ARM_THUMBEE
ARM: 7382/1: mm: truncate memory banks to fit in 4GB space for classic MMU
ARM: 7359/2: smp_twd: Only wait for reprogramming on active cpus
ARM: 7383/1: nommu: populate vectors page from paging_init
ARM: 7381/1: nommu: fix typo in mm/Kconfig
ARM: 7380/1: DT: do not add a zero-sized memory property
ARM: 7379/1: DT: fix atags_to_fdt() second call site
ARM: 7366/3: amba: Remove AMBA level regulator support
ARM: 7377/1: vic: re-read status register before dispatching each IRQ handler
ARM: 7368/1: fault.c: correct how the tsk->[maj|min]_flt gets incremented
GCC's NULL is actually __null, which allows detecting some questionable
NULL usage and warn about it. Moreover each platform/compiler should
have its own stddef.h anyway (which is different from linux/stddef.h).
So there's no good reason to leak kernel's NULL to userspace and
override what the compiler provides.
Signed-off-by: Luboš Luňák <l.lunak@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull block core bits from Jens Axboe:
"It's a nice and quiet round this time, since most of the tricky stuff
has been pushed to 3.5 to give it more time to mature. After a few
hectic block IO core changes for 3.3 and 3.2, I'm quite happy with a
slow round.
Really minor stuff in here, the only real functional change is making
the auto-unplug threshold a per-queue entity. The threshold is set so
that it's low enough that we don't hold off IO for too long, but still
big enough to get a nice benefit from the batched insert (and hence
queue lock cost reduction). For raid configurations, this currently
breaks down."
* 'for-3.4/core' of git://git.kernel.dk/linux-block:
block: make auto block plug flush threshold per-disk based
Documentation: Add sysfs ABI change for cfq's target latency.
block: Make cfq_target_latency tunable through sysfs.
block: use lockdep_assert_held for queue locking
block: blk_alloc_queue_node(): use caller's GFP flags instead of GFP_KERNEL
Pull SPI bug fixes from Grant Likely:
"Miscellaneous driver bug fixes. No major changes in this branch."
* tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6:
spi/imx: prevent NULL pointer dereference in spi_imx_probe()
spi/imx: mark base member in spi_imx_data as __iomem
spi/mpc83xx: fix NULL pdata dereference bug
spi/davinci: Fix DMA API usage in davinci
spi/pL022: include types.h to remove compilation warnings
The AMBA bus regulator support is being used to model on/off switches
for power domains which isn't terribly idiomatic for modern kernels with
the generic power domain code and creates integration problems on platforms
which don't use regulators for their power domains as it's hard to tell
the difference between a regulator that is needed but failed to be provided
and one that isn't supposed to be there (though DT does make that easier).
Platforms that wish to use the regulator API to manage their power domains
can indirect via the power domain interface.
This feature is only used with the vape supply of the db8500 PRCMU
driver which supplies the UARTs and MMC controllers, none of which have
support for managing vcore at runtime in mainline (only pl022 SPI
controller does). Update that supply to have an always_on constraint
until the power domain support for the system is updated so that it is
enabled for these users, this is likely to have no impact on practical
systems as probably at least one of these devices will be active and
cause AMBA to hold the supply on anyway.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Using IS_ENABLED() within C (vs. within CPP #if statements) in its
current form requires us to actually define every possible bool/tristate
Kconfig option twice (__enabled_* and __enabled_*_MODULE variants).
This results in a huge autoconf.h file, on the order of 16k lines for a
x86_64 defconfig.
Fixing IS_ENABLED to be able to work on the smaller subset of just
things that we really have defined is step one to fixing this. Which
means it has to not choke when fed non-enabled options, such as:
include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef]
The original prototype of how to implement a C and preprocessor
compatible way of doing this came from the Google+ user "comex ." in
response to Linus' crowdsourcing challenge for a possible improvement on
his earlier C specific solution:
#define config_enabled(x) (__stringify(x)[0] == '1')
In this implementation, I've chosen variable names that hopefully make
how it works more understandable.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull USB fixes from Greg KH:
"Here are a number of fixes for the USB core and drivers for 3.4-rc2
Lots of tiny xhci fixes here, a few usb-serial driver fixes and new
device ids, and a smattering of other minor fixes in different USB
drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'usb-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (30 commits)
USB: update usbtmc api documentation
xHCI: Correct the #define XHCI_LEGACY_DISABLE_SMI
xHCI: use gfp flags from caller instead of GFP_ATOMIC
xHCI: add XHCI_RESET_ON_RESUME quirk for VIA xHCI host
USB: fix bug of device descriptor got from superspeed device
xhci: Fix register save/restore order.
xhci: Restore event ring dequeue pointer on resume.
xhci: Don't write zeroed pointers to xHC registers.
xhci: Warn when hosts don't halt.
xhci: don't re-enable IE constantly
usb: xhci: fix section mismatch in linux-next
xHCI: correct to print the true HSEE of USBCMD
USB: serial: fix race between probe and open
UHCI: hub_status_data should indicate if ports are resuming
EHCI: keep track of ports being resumed and indicate in hub_status_data
USB: fix race between root-hub suspend and remote wakeup
USB: sierra: add support for Sierra Wireless MC7710
USB: ftdi_sio: fix race condition in TIOCMIWAIT, and abort of TIOCMIWAIT when the device is removed
USB: ftdi_sio: fix status line change handling for TIOCMIWAIT and TIOCGICOUNT
USB: don't ignore suspend errors for root hubs
...
Pull tty and serial fixes from Greg KH:
"Here are some tty and serial fixes for 3.4-rc2.
Most important here is the pl011 fix, which has been reported by about
100 different people, which means more people use it than I expected
:)
There are also some 8250 driver reverts due to some problems reported
by them. And other minor fixes as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'tty-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
pch_uart: Add Kontron COMe-mTT10 uart clock quirk
pch_uart: Fix MSI setting issue
serial/8250_pci: add a "force background timer" flag and use it for the "kt" serial port
Revert "serial/8250_pci: setup-quirk workaround for the kt serial controller"
Revert "serial/8250_pci: init-quirk msi support for kt serial controller"
tty/serial/omap: console can only be built-in
serial: samsung: fix omission initialize ulcon in reset port fn()
printk(): add KERN_CONT where needed in hpet and vt code
tty/serial: atmel_serial: fix RS485 half-duplex problem
tty: serial: altera_uart: Check for NULL platform_data in probe.
isdn/gigaset: use gig_dbg() for debugging output
omap-serial: Fix the error handling in the omap_serial probe
serial: PL011: move interrupt clearing
Pull networking fixes from David Miller:
1) Fix bluetooth userland regression reported by Keith Packard, from
Gustavo Padovan.
2) Revert ath9k PS idle change, from Sujith Manoharan.
3) Correct default TCP memory limits (again), from Eric Dumazet.
4) Fix tcp_rcv_rtt_update() accidental use of unscaled RTT, from Neal
Cardwell.
5) We made a facility for layers like wireless to say how much tailroom
they need in the SKB for link layer stuff such as wireless
encryption etc., but TCP works hard to fill every SKB out to the end
defeating this specification.
This leads to every TCP packet getting reallocated by the wireless
code in order to have the right amount of tailroom available.
Fix TCP to only fill SKBs out to the real amount of data area it
asked for during the allocation, this way it won't eat into the
slack added for the device's tailroom needs.
Reported by Marc Merlin and fixed by Eric Dumazet.
6) Leaks, endian bugs, and new device IDs in bluetooth from Santosh
Nayak, João Paulo Rechi Vita, Cho, Yu-Chen, Andrei Emeltchenko,
AceLan Kao, and Andrei Emeltchenko.
7) OOPS on tty_close fix in bluetooth's hci_ldisc from Johan Hovold.
8) netfilter erroneously scales TCP window twice, fix from Changli Gao.
9) Memleak fix in wext-core from Julia Lawall.
10) Consistently handle invalid TCP packets in ipv4 vs. ipv6 conntrack,
from Jozsef Kadlecsik.
11) Validate IP header length properly in netfilter conntrack's
ipv4_get_l4proto().
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (39 commits)
NFC: Fix the LLCP Tx fragmentation loop
rtlwifi: Add missing DMA buffer unmapping for PCI drivers
rtlwifi: Preallocate USB read buffers and eliminate kalloc in read routine
tcp: avoid order-1 allocations on wifi and tx path
net: allow pskb_expand_head() to get maximum tailroom
bridge: Do not send queries on multicast group leaves
MAINTAINERS: Mark NATSEMI driver as orphan'd.
tcp: fix tcp_rcv_rtt_update() use of an unscaled RTT sample
tcp: restore correct limit
Revert "ath9k: fix going to full-sleep on PS idle"
rt2x00: Fix rfkill_polling register function.
bcma: fix build error on MIPS; implicit pcibios_enable_device
netfilter: nf_conntrack: fix incorrect logic in nf_conntrack_init_net
netfilter: nf_ct_ipv4: packets with wrong ihl are invalid
netfilter: nf_ct_ipv4: handle invalid IPv4 and IPv6 packets consistently
net/wireless/wext-core.c: add missing kfree
rtlwifi: Fix oops on rate-control failure
mac80211: Convert WARN_ON to WARN_ON_ONCE
rtlwifi: rtl8192de: Fix firmware initialization
nl80211: ensure interface is up in various APIs
...
Pull drm fixes from Dave Airlie:
"Mostly exynos and intel.
Intel has 3 regression fixers (more info in intel merge commit), along
with some other make hw work fixes, exynos has some cleanups and an
ioctl fix.
A couple of radeon fixes, couple of build fixes, and a savage
userspace interface possible overflow fix."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (23 commits)
drm/exynos: fixed exynos broken ioctl
drm/i915: clear fencing tracking state when retiring requests
drm/exynos: fix to pointer manager member of struct exynos_drm_subdrv
drm/exynos: fix struct for operation callback functions to driver name
drm/exynos: use define instead of default_win member in struct mixer_context
drm/exynos: rename s/HDMI_OVERLAY_NUMBER/MIXER_WIN_NR
drm/exynos: remove unused codes in hdmi and mixer
drm/exynos: remove unnecessary type conversion of hdmi and mixer
drm/i915: make rc6 module parameter read-only
drm/i915: implement ColorBlt w/a
drm/i915/ringbuffer: Exclude last 2 cachlines of ring on 845g
Revert "drm/i915: reenable gmbus on gen3+ again"
drm/radeon: only add the mm i2c bus if the hw_i2c module param is set
vgaarb.h: fix build warnings
drm/i915: properly compute dp dithering for user-created modes
drm/radeon/kms: fix DVO setup on some r4xx chips
drm/savage: fix integer overflows in savage_bci_cmdbuf()
drm/radeon: replace udelay with mdelay for long timeouts
drm/i915: Finish any pending operations on the framebuffer before disabling
drm/i915: Removed IVB forced enable of sprite dest key.
...
Pull irqdomain bug fixes from Grant Likely:
"This branch fixes a bug in irq_create_mapping() where an error return
from irq_alloc_desc_from() gets ignored.
It also removes irq_virq_count to fix a bug on powerpc where the
irqdomain code does not find irqs allocated above the CONFIG_NR_IRQS
boundary.
The remaining patches get rid of an completely pointless export and
fix some minor bugs in the irqdomain debug output."
* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6:
irq_domain: Move irq_virq_count into NOMAP revmap
irqdomain: Fix debugfs formatting
irq_domain: correct the debugfs file name
irq: Kill pointless irqd_to_hw export
irq/irq_domain: Quit ignoring error returns from irq_alloc_desc_from().
Use the ISO C standard compliant form instead of the gcc extension in the
interface definition.
Reported-by: Shachar Sharon <ssnail@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
This patch replaces the old global setting of irq_virq_count that is only
used by the NOMAP mapping and instead uses a revmap_data property so that
the maximum NOMAP allocation can be set per NOMAP irq_domain.
There is exactly one user of irq_virq_count in-tree right now: PS3.
Also, irq_virq_count is only useful for the NOMAP mapping. So,
instead of having a single global irq_virq_count values, this change
drops it entirely and added a max_irq argument to irq_domain_add_nomap().
That makes it a property of an individual nomap irq domain instead of
a global system settting.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
We've been adding new mappings, but not destroying old mappings.
This can lead to a page leak as pages are pinned using
get_user_pages, but only unpinned with put_page if they still
exist in the memslots list on vm shutdown. A memslot that is
destroyed while an iommu domain is enabled for the guest will
therefore result in an elevated page reference count that is
never cleared.
Additionally, without this fix, the iommu is only programmed
with the first translation for a gpa. This can result in
peer-to-peer errors if a mapping is destroyed and replaced by a
new mapping at the same gpa as the iommu will still be pointing
to the original, pinned memory address.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Marc Merlin reported many order-1 allocations failures in TX path on its
wireless setup, that dont make any sense with MTU=1500 network, and non
SG capable hardware.
After investigation, it turns out TCP uses sk_stream_alloc_skb() and
used as a convention skb_tailroom(skb) to know how many bytes of data
payload could be put in this skb (for non SG capable devices)
Note : these skb used kmalloc-4096 (MTU=1500 + MAX_HEADER +
sizeof(struct skb_shared_info) being above 2048)
Later, mac80211 layer need to add some bytes at the tail of skb
(IEEE80211_ENCRYPT_TAILROOM = 18 bytes) and since no more tailroom is
available has to call pskb_expand_head() and request order-1
allocations.
This patch changes sk_stream_alloc_skb() so that only
sk->sk_prot->max_header bytes of headroom are reserved, and use a new
skb field, avail_size to hold the data payload limit.
This way, order-0 allocations done by TCP stack can leave more than 2 KB
of tailroom and no more allocation is performed in mac80211 layer (or
any layer needing some tailroom)
avail_size is unioned with mark/dropcount, since mark will be set later
in IP stack for output packets. Therefore, skb size is unchanged.
Reported-by: Marc MERLIN <marc@merlins.org>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix build warnings by providing a struct stub since no fields of
the struct are used:
include/linux/vgaarb.h:66:9: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:66:9: warning: its scope is only this definition or declaration, which is probably not what you want
include/linux/vgaarb.h:99:34: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:109:6: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:121:8: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:140:37: warning: 'struct pci_dev' declared inside parameter list
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Macros in <linux/pinctrl/machine.h> call ARRAY_SIZE(), the definition of
which eventually calls BUILD_BUG_ON_ZERO(), which is defined in
<linux/bug.h>. Include that so that every .c file using the pinctrl macros
doesn't have to do that itself.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The pinctrl_register_mappings is defined in core.c, so change the dependent
macro from CONFIG_MUX to CONFIG_PINCTRL.
The compile error message is:
drivers/pinctrl/core.c:886: error: redefinition of 'pinctrl_register_mappings'
include/linux/pinctrl/machine.h:160: note: previous definition of 'pinctrl_register_mappings' was here
make[2]: *** [drivers/pinctrl/core.o] Error 1
make[1]: *** [drivers/pinctrl] Error 2
make: *** [drivers] Error 2
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It makes no sense to export this trivial function. Make it a static inline
instead.
This patch also drops virq_to_hw from arch/c6x since it is unused by that
architecture.
v2: Move irq_hw_number_t into types.h to fix ARM build failure
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull dmaengine fixes from Dan Williams:
1/ regression fix for Xen as it now trips over a broken assumption
about the dma address size on 32-bit builds
2/ new quirk for netdma to ignore dma channels that cannot meet
netdma alignment requirements
3/ fixes for two long standing issues in ioatdma (ring size overflow)
and iop-adma (potential stack corruption)
* tag 'dmaengine-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
netdma: adding alignment check for NETDMA ops
ioatdma: DMA copy alignment needed to address IOAT DMA silicon errata
ioat: ring size variables need to be 32bit to avoid overflow
iop-adma: Corrected array overflow in RAID6 Xscale(R) test.
ioat: fix size of 'completion' for Xen
