The struct pinctrl_dev's node field is not properly set up, which means
the .prev and .next fields will be NULL. That's not something that the
linked list code can deal with, so extra care must be taken when using
these fields. An example of this is introduced in commit 3429fb3cda
("pinctrl: Fix panic when pinctrl devices with hogs are unregistered")
where list_del() is made conditional on the pinctrl device being part
of the pinctrl device list. This is to ensure that list_del() won't
crash upon encountering a NULL pointer in .prev and/or .next.
After initializing the list head there's no need to jump through these
extra hoops and list_del() will work unconditionally. This is because
the initialized list head points to itself and therefore the .prev and
.next fields can be properly dereferenced.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Commit df61b366af26 ("pinctrl: core: Use delayed work for hogs") caused a
regression at least with sh-pfc that is also a GPIO controller as
noted by Geert Uytterhoeven <geert@linux-m68k.org>.
As the original pinctrl_register() has issues calling pin controller
driver functions early before the controller has finished registering,
we can't just revert commit df61b366af26. That would break the drivers
using GENERIC_PINCTRL_GROUPS or GENERIC_PINMUX_FUNCTIONS.
So let's fix the issue with the following steps as a single patch:
1. Revert the late_init parts of commit df61b366af26.
The late_init clearly won't work and we have to just give up
on fixing pinctrl_register() for GENERIC_PINCTRL_GROUPS and
GENERIC_PINMUX_FUNCTIONS.
2. Split pinctrl_register() into two parts
By splitting pinctrl_register() into pinctrl_init_controller()
and pinctrl_create_and_start() we have better control over when
it's safe to call pinctrl_create().
3. Introduce a new pinctrl_register_and_init() function
As suggested by Linus Walleij <linus.walleij@linaro.org>, we
can just introduce a new function for the controllers that need
pinctrl_create() called later.
4. Convert the four known problem cases to use new function
Let's convert pinctrl-imx, pinctrl-single, sh-pfc and ti-iodelay
to use the new function to fix the issues. The rest of the drivers
can be converted later. Let's also update Documentation/pinctrl.txt
accordingly because of the known issues with pinctrl_register().
Fixes: df61b366af26 ("pinctrl: core: Use delayed work for hogs")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
V3s SoC features only a pin controller (for the lack of CPUs part).
Add a driver for this controller.
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We accidentally deleted two tabs from the first line, but even with that
fixed the conditions were not really kernel style. Put the && at the
end of the line so we can align the condition clauses. Also add spaces
around the "+" operator.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Upon failing kzalloc() will print an error message in the log, so
there's no need for additional printouts. Also standardizes the "!ptr"
vs "ptr == NULL" while I'm touching those lines.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds the pintrol-da850-pupd driver to the module device table so that
udev will automatically bind the driver to the device.
Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This simplifies error handling and allows us to drop error path handlers
completely.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This simplifies error handling and allows us to drop intel_pinctrl_remove()
completely.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
SoC family such as DRA7 family of processors have, in addition
to the regular muxing of pins (as done by pinctrl-single), a separate
hardware module called IODelay which is also expected to be configured.
The "IODelay" module has it's own register space that is independent
of the control module and the padconf register area.
With recent changes to the pinctrl framework, we can now support
this hardware with a reasonably minimal driver by using #pinctrl-cells,
GENERIC_PINCTRL_GROUPS and GENERIC_PINMUX_FUNCTIONS.
It is advocated strongly in TI's official documentation considering
the existing design of the DRA7 family of processors during mux or
IODelay reconfiguration, there is a potential for a significant glitch
which may cause functional impairment to certain hardware. It is
hence recommended to do as little of muxing as absolutely necessary
without I/O isolation (which can only be done in initial stages of
bootloader).
NOTE: with the system wide I/O isolation scheme present in DRA7 SoC
family, it is not reasonable to do stop all I/O operations for every
such pad configuration scheme. So, we will let it glitch when used in
this mode.
Even with the above limitation, certain functionality such as MMC has
mandatory need for IODelay reconfiguration requirements, depending on
speed of transfer. In these cases, with careful examination of usecase
involved, the expected glitch can be controlled such that it does not
impact functionality.
In short, IODelay module support as a padconf driver being introduced
here is not expected to do SoC wide I/O Isolation and is meant for
a limited subset of IODelay configuration requirements that need to
be dynamic and whose glitchy behavior will not cause functionality
failure for that interface.
IMPORTANT NOTE: we take the approach of keeping LOCK_BITs cleared
to 0x0 at all times, even when configuring Manual IO Timing Modes.
This is done by eliminating the LOCK_BIT=1 setting from Step
of the Manual IO timing Mode configuration procedure. This option
leaves the CFG_* registers unprotected from unintended writes to the
CTRL_CORE_PAD_* registers while Manual IO Timing Modes are configured.
This approach is taken to allow for a generic driver to exist in kernel
world that has to be used carefully in required usecases.
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
[tony@atomide.com: updated to use generic pinctrl functions, added
binding documentation, updated comments]
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If the pin controller driver is using devm_kzalloc, there may not be
anything to do for dt_free_map. Let's make it optional to avoid
unncessary boilerplate code.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Now that we have a common pinctrl driver for all the sun5i SoCs, we can
remove the old, separate drivers.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The sun5i SoCs (A10s, A13, GR8) are all based on the same die fit in
different packages. Hence, the pins and functions available are just the
based on the same set, each SoC having a different subset.
Introduce a common pinctrl driver that supports multiple variants to allow
to put as much as we can in common.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Some SoCs are either supposed to be pin compatible (A10 and A20 for
example), or are just repackaged versions of the same die (A10s, A13, GR8).
In those case, having a full blown pinctrl driver just introduces
duplication in both data size and maintainance effort.
Add a variant option to both pins and functions to be able to limit the
pins and functions described only to a subset of the SoC we support with a
given driver.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Commit df61b366af26 ('pinctrl: core: Use delayed work for hogs')
deferred part of the registration for pinctrl devices if the pinctrl
device has hogs. This introduced a window where if the pinctrl device
with hogs was sucessfully registered, but then unregistered again
(which could be caused by parent device being probe deferred) before
the delayed work has chanced to run, then this will cause a kernel
panic to occur because:
1. The 'pctldev->p' has not yet been initialised and when unregistering
the pinctrl device we only check to see if it is an error value, but
now it could also be NULL.
2. The pinctrl device may not have been added to the 'pinctrldev_list'
list and we don't check to see if it was added before removing.
Fix up the above by checking to see if the 'pctldev->p' pointer is an
error value or NULL before putting the pinctrl device and verifying
that the pinctrl device is present in 'pinctrldev_list' before removing.
Fixes: df61b366af26 ('pinctrl: core: Use delayed work for hogs')
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
3bfd44306c ("pinctrl: amd: Add support for additional GPIO")
created the following warning:
drivers/pinctrl/pinctrl-amd.c: In function 'amd_gpio_dbg_show':
drivers/pinctrl/pinctrl-amd.c:210:3: warning: 'pin_num' may be used uninitialized in this function [-Wmaybe-uninitialized]
for (; i < pin_num; i++) {
^
drivers/pinctrl/pinctrl-amd.c:172:21: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized]
unsigned int bank, i, pin_num;
^
Fix this by adding a guarding default case for illegal
bank numbers.
Cc: S-k Shyam-sundar <Shyam-sundar.S-k@amd.com>
Cc: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Now using function_desc structure instead of imx_pmx_func.
Also leveraging generic functions to retrieve functions count/name/groups.
The imx_free_funcs function can be removed since it is now handled by
the core driver during unregister.
Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Now using group_desc structure instead of imx_pin_group.
Also leveraging generic functions to retrieve groups count/name/pins.
The imx_free_pingroups function can be removed since it is now handled by
the core driver during unregister.
Finally the device tree parsing is moved after the pinctrl driver registration
since this latter initializes the radix trees.
Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
These four pins are for SDC4, not SDC1. They are grouped for
SDC4 later in the file so this must be a typo.
Reviewed-by: Björn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We can now drop the driver specific code for managing functions.
Signed-off-by: Tony Lindgren <tony@atomide.com>
[Replaces GENERIC_PINMUX with GENERIC_PINMUX_FUNCTIONS]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We can now drop the driver specific code for managing groups.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We can add generic helpers for function handling for cases where the pin
controller driver does not need to use static arrays.
Signed-off-by: Tony Lindgren <tony@atomide.com>
[Renamed the Kconfig item and moved things around]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Rename the symbol PINCTRL_GENERIC to PINCTRL_GENERIC_GROUPS since
it all pertains to groups. Replace everywhere.
ifdef out the radix tree and the struct when not using the
generic groups.
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We can add generic helpers for pin group handling for cases where the pin
controller driver does not need to use static arrays.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It confused me a bit so it may confuse others. Make it crystal
clear what is going on here for any future readers.
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Having the pin control framework call pin controller functions
before it's probe has finished is not nice as the pin controller
device driver does not yet have struct pinctrl_dev handle.
Let's fix this issue by adding deferred work for late init. This is
needed to be able to add pinctrl generic helper functions that expect
to know struct pinctrl_dev handle. Note that we now need to call
create_pinctrl() directly as we don't want to add the pin controller
to the list of controllers until the hogs are claimed. We also need
to pass the pinctrl_dev to the device tree parser functions as they
otherwise won't find the right controller at this point.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This change is inspired from the pinctrl-single architecture.
The problem with current implementation is that it isn't possible
to add/remove functions and/or groups dynamically. The radix tree
offers an easy way to do so. The intent is to offer a follow-up
patch later that will enable the use of pinctrl nodes in dt-overlays.
Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Otherwise can't dynamically update fields such as ngroups which can
change over time (with a dt-overlay for instance).
Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Trivial fixe to spelling mistake "Ivalid" to "Invalid" in
dev_err error message.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This is a non-functional change, which deletes code duplication in two
of four if-if branches by reordering the checks. Functional identity
of the code change can be shown by running through the whole truth table
of boolean arguments.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch updates my email address as I no longer have access to the old
one.
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add some tab in order to improve indentation.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reference to 'sys2pci_np' should be dropped in all cases here, not only in
error handling path.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This activates strict mode muxing for the STM32 pin controllers,
as these do not allow GPIO and functions to use the same pin
simultaneously.
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
On Marvell mv88f6180 mpp pins range from 0 to 19 as well as from 35 to 44.
This is already fixed in commit: 9573e79230
This is the documentation change for above commit.
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch adds support for new Bank and adds IRQCHIP_SKIP_SET_WAKE flag.
Reviewed-by: S-k, Shyam-sundar <Shyam-sundar.S-k@amd.com>
Signed-off-by: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The patch introducing the g5 pinctrl driver implemented a smattering of
pins to flesh out the implementation of the core and provide bare-bones
support for some OpenPOWER platforms and the AST2500 evaluation board.
Now, update the bindings document to reflect the complete functionality
and implement the necessary pin configuration tables in the driver.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The patch introducing the g4 pinctrl driver implemented a smattering of
pins to flesh out the implementation of the core and provide bare-bones
support for some OpenPOWER platforms. Now, update the bindings document
to reflect the complete functionality and implement the necessary pin
configuration tables in the driver.
Cc: Timothy Pearson <tpearson@raptorengineering.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The System Control Unit IP block in the Aspeed SoCs is typically where
the pinmux configuration is found, but not always. A number of pins
depend on state in one of LPC Host Control (LHC) or SoC Display
Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
means to adjust these as necessary.
We use syscon to cast a regmap over the GFX and LPC blocks, which is
used as an arbitration layer between the relevant driver and the pinctrl
subsystem. The regmaps are then exposed to the SoC-specific pinctrl
drivers by phandles in the devicetree, and are selected during a mux
request by querying a new 'ip' member in struct aspeed_sig_desc.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reference the SoC-specific compatible string in the examples as
required.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
I am getting the following warning when I build kernel 4.9-git on my
PowerBook G4 with a 32-bit PPC processor:
AS arch/powerpc/kernel/misc_32.o
arch/powerpc/kernel/misc_32.S:299:7: warning: "CONFIG_FSL_BOOKE" is not defined [-Wundef]
This problem is evident after commit 989cea5c14 ("kbuild: prevent
lib-ksyms.o rebuilds"); however, this change in kbuild only exposes an
error that has been in the code since 2005 when this source file was
created. That was with commit 9994a33865 ("powerpc: Introduce
entry_{32,64}.S, misc_{32,64}.S, systbl.S").
The offending line does not make a lot of sense. This error does not
seem to cause any errors in the executable, thus I am not recommending
that it be applied to any stable versions.
Thanks to Nicholas Piggin for suggesting this solution.
Fixes: 9994a33865 ("powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S")
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The timer type simplifications caused a new gcc warning:
drivers/base/power/domain.c: In function ‘genpd_runtime_suspend’:
drivers/base/power/domain.c:562:14: warning: ‘time_start’ may be used uninitialized in this function [-Wmaybe-uninitialized]
elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
despite the actual use of "time_start" not having changed in any way.
It appears that simply changing the type of ktime_t from a union to a
plain scalar type made gcc check the use.
The variable wasn't actually used uninitialized, but gcc apparently
failed to notice that the conditional around the use was exactly the
same as the conditional around the initialization of that variable.
Add an unnecessary initialization just to shut up the compiler.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull timer type cleanups from Thomas Gleixner:
"This series does a tree wide cleanup of types related to
timers/timekeeping.
- Get rid of cycles_t and use a plain u64. The type is not really
helpful and caused more confusion than clarity
- Get rid of the ktime union. The union has become useless as we use
the scalar nanoseconds storage unconditionally now. The 32bit
timespec alike storage got removed due to the Y2038 limitations
some time ago.
That leaves the odd union access around for no reason. Clean it up.
Both changes have been done with coccinelle and a small amount of
manual mopping up"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ktime: Get rid of ktime_equal()
ktime: Cleanup ktime_set() usage
ktime: Get rid of the union
clocksource: Use a plain u64 instead of cycle_t
Pull SMP hotplug notifier removal from Thomas Gleixner:
"This is the final cleanup of the hotplug notifier infrastructure. The
series has been reintgrated in the last two days because there came a
new driver using the old infrastructure via the SCSI tree.
Summary:
- convert the last leftover drivers utilizing notifiers
- fixup for a completely broken hotplug user
- prevent setup of already used states
- removal of the notifiers
- treewide cleanup of hotplug state names
- consolidation of state space
There is a sphinx based documentation pending, but that needs review
from the documentation folks"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/armada-xp: Consolidate hotplug state space
irqchip/gic: Consolidate hotplug state space
coresight/etm3/4x: Consolidate hotplug state space
cpu/hotplug: Cleanup state names
cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions
staging/lustre/libcfs: Convert to hotplug state machine
scsi/bnx2i: Convert to hotplug state machine
scsi/bnx2fc: Convert to hotplug state machine
cpu/hotplug: Prevent overwriting of callbacks
x86/msr: Remove bogus cleanup from the error path
bus: arm-ccn: Prevent hotplug callback leak
perf/x86/intel/cstate: Prevent hotplug callback leak
ARM/imx/mmcd: Fix broken cpu hotplug handling
scsi: qedi: Convert to hotplug state machine
Pull turbostat updates from Len Brown.
* 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: remove obsolete -M, -m, -C, -c options
tools/power turbostat: Make extensible via the --add parameter
tools/power turbostat: Denverton uses a 25 MHz crystal, not 19.2 MHz
tools/power turbostat: line up headers when -M is used
tools/power turbostat: fix SKX PKG_CSTATE_LIMIT decoding
tools/power turbostat: Support Knights Mill (KNM)
tools/power turbostat: Display HWP OOB status
tools/power turbostat: fix Denverton BCLK
tools/power turbostat: use intel-family.h model strings
tools/power/turbostat: Add Denverton RAPL support
tools/power/turbostat: Add Denverton support
tools/power/turbostat: split core MSR support into status + limit
tools/power turbostat: fix error case overflow read of slm_freq_table[]
tools/power turbostat: Allocate correct amount of fd and irq entries
tools/power turbostat: switch to tab delimited output
tools/power turbostat: Gracefully handle ACPI S3
tools/power turbostat: tidy up output on Joule counter overflow
Add a new page flag, PageWaiters, to indicate the page waitqueue has
tasks waiting. This can be tested rather than testing waitqueue_active
which requires another cacheline load.
This bit is always set when the page has tasks on page_waitqueue(page),
and is set and cleared under the waitqueue lock. It may be set when
there are no tasks on the waitqueue, which will cause a harmless extra
wakeup check that will clears the bit.
The generic bit-waitqueue infrastructure is no longer used for pages.
Instead, waitqueues are used directly with a custom key type. The
generic code was not flexible enough to have PageWaiters manipulation
under the waitqueue lock (which simplifies concurrency).
This improves the performance of page lock intensive microbenchmarks by
2-3%.
Putting two bits in the same word opens the opportunity to remove the
memory barrier between clearing the lock bit and testing the waiters
bit, after some work on the arch primitives (e.g., ensuring memory
operand widths match and cover both bits).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A page is not added to the swap cache without being swap backed,
so PageSwapBacked mappings can use PG_owner_priv_1 for PageSwapCache.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
No point in going through loops and hoops instead of just comparing the
values.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Thierry Reding