The rcu_all_qs() and rcu_note_context_switch() do a series of checks,
taking various actions to supply RCU with quiescent states, depending
on the outcomes of the various checks. This is a bit much for scheduling
fastpaths, so this commit creates a separate ->rcu_urgent_qs field in
the rcu_dynticks structure that acts as a global guard for these checks.
Thus, in the common case, rcu_all_qs() and rcu_note_context_switch()
check the ->rcu_urgent_qs field, find it false, and simply return.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
The rcu_momentary_dyntick_idle() function scans the RCU flavors, checking
that one of them still needs a quiescent state before doing an expensive
atomic operation on the ->dynticks counter. However, this check reduces
overhead only after a rare race condition, and increases complexity. This
commit therefore removes the scan and the mechanism enabling the scan.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcu_qs_ctr variable is yet another isolated per-CPU variable,
so this commit pulls it into the pre-existing rcu_dynticks per-CPU
structure.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcu_sched_qs_mask variable is yet another isolated per-CPU variable,
so this commit pulls it into the pre-existing rcu_dynticks per-CPU
structure.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current use of "RCU_TRACE(statement);" can cause odd bugs, especially
where "statement" is a local-variable declaration, as it can leave a
misplaced ";" in the source code. This commit therefore converts these
to "RCU_TRACE(statement;)", which avoids the misplaced ";".
Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current use of "RCU_TRACE(statement);" can cause odd bugs, especially
where "statement" is a local-variable declaration, as it can leave a
misplaced ";" in the source code. This commit therefore converts these
to "RCU_TRACE(statement;)", which avoids the misplaced ";".
Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current use of "RCU_TRACE(statement);" can cause odd bugs, especially
where "statement" is a local-variable declaration, as it can leave a
misplaced ";" in the source code. This commit therefore converts these
to "RCU_TRACE(statement;)", which avoids the misplaced ";".
Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Users of SRCU are obliged to complete all grace-period activity before
invoking cleanup_srcu_struct(). This means that all calls to either
synchronize_srcu() or synchronize_srcu_expedited() must have returned,
and all calls to call_srcu() must have returned, and the last call to
call_srcu() must have been followed by a call to srcu_barrier().
Furthermore, the caller must have done something to prevent any
further calls to synchronize_srcu(), synchronize_srcu_expedited(),
and call_srcu().
Therefore, if there has ever been an invocation of call_srcu() on
the srcu_struct in question, the sequence of events must be as
follows:
1. Prevent any further calls to call_srcu().
2. Wait for any pre-existing call_srcu() invocations to return.
3. Invoke srcu_barrier().
4. It is now safe to invoke cleanup_srcu_struct().
On the other hand, if there has ever been a call to synchronize_srcu()
or synchronize_srcu_expedited(), the sequence of events must be as
follows:
1. Prevent any further calls to synchronize_srcu() or
synchronize_srcu_expedited().
2. Wait for any pre-existing synchronize_srcu() or
synchronize_srcu_expedited() invocations to return.
3. It is now safe to invoke cleanup_srcu_struct().
If there have been calls to all both types of functions (call_srcu()
and either of synchronize_srcu() and synchronize_srcu_expedited()), then
the caller must do the first three steps of the call_srcu() procedure
above and the first two steps of the synchronize_s*() procedure above,
and only then invoke cleanup_srcu_struct().
Note that cleanup_srcu_struct() does some probabilistic checks
for the caller failing to follow these procedures, in which case
cleanup_srcu_struct() does WARN_ON() and avoids freeing the per-CPU
structures associated with the specified srcu_struct structure.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Temporary got a Lifebook E547 into my hands and noticed the touchpad
only works after running:
echo "1" > /sys/devices/platform/i8042/serio2/crc_enabled
Add it to the list of machines that need this workaround.
Cc: stable@vger.kernel.org
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Reviewed-by: Ulrik De Bie <ulrik.debie-os@e2big.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
When switching rotary controlelr from plain IRQ number to IRQ resource, I
messed up the syntax.
Fixes: d422be5f62 ("Input: eeti_ts - expect platform code to set ... ")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Do not recommend people write to Dominic, rather everyone should be using
linux-input mailing list.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The srcu_reschedule() function invokes rcu_batch_empty() on each of
the four rcu_batch structures in the srcu_struct in question twice.
Given that this check will also be needed in cleanup_srcu_struct(), this
commit consolidates these four checks into a new rcu_all_batches_empty()
function.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The definition of smp_mb__after_unlock_lock() is currently smp_mb()
for CONFIG_PPC and a no-op otherwise. It would be better to instead
provide an architecture-selectable Kconfig option, and select the
strength of smp_mb__after_unlock_lock() based on that option. This
commit therefore creates ARCH_WEAK_RELEASE_ACQUIRE, has PPC select it,
and bases the definition of smp_mb__after_unlock_lock() on this new
ARCH_WEAK_RELEASE_ACQUIRE Kconfig option.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Boqun Feng <boqun.feng@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <linuxppc-dev@lists.ozlabs.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Currently, IPIs are used to force other CPUs to invalidate their TLBs
in response to a kernel virtual-memory mapping change. This works, but
degrades both battery lifetime (for idle CPUs) and real-time response
(for nohz_full CPUs), and in addition results in unnecessary IPIs due to
the fact that CPUs executing in usermode are unaffected by stale kernel
mappings. It would be better to cause a CPU executing in usermode to
wait until it is entering kernel mode to do the flush, first to avoid
interrupting usemode tasks and second to handle multiple flush requests
with a single flush in the case of a long-running user task.
This commit therefore reserves a bit at the bottom of the ->dynticks
counter, which is checked upon exit from extended quiescent states.
If it is set, it is cleared and then a new rcu_eqs_special_exit() macro is
invoked, which, if not supplied, is an empty single-pass do-while loop.
If this bottom bit is set on -entry- to an extended quiescent state,
then a WARN_ON_ONCE() triggers.
This bottom bit may be set using a new rcu_eqs_special_set() function,
which returns true if the bit was set, or false if the CPU turned
out to not be in an extended quiescent state. Please note that this
function refuses to set the bit for a non-nohz_full CPU when that CPU
is executing in usermode because usermode execution is tracked by RCU
as a dyntick-idle extended quiescent state only for nohz_full CPUs.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The dw_mmio driver disables the block clock before unregistering
the host. The code unregistering the host may access the SPI block
registers. If register access happens with block clock disabled,
this may lead to a bus hang. Disable the clock after unregistering
the host to prevent such situation.
This bug was observed on Altera Cyclone V SoC.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Benjamin Herrenschmidt says:
====================
ftgmac100: Rework batch 5 - Features
This is the third spin of the fifth and last batch of
updates to the ftgmac100 driver.
This contains a few additional "features" such as:
- Support for ethtool n-way reset
- Multicast filtering & promisc support
- Vlan offload
- netpoll
And a couple of misc bits. This also adds the device-tree binding
documentation.
v2. - Addresses review comments and adds a new patch fixing a
theorical ordering issue in my new NAPI poll implementation
- Add a bug fix (Patch 8/9) for a potential ordering issue
in the new NAPI poll code.
v3. - Rebase on net-next (fix conflict with an unrelated #include
change series)
- Update DT bindings better describing accepted phy-mode values
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to ensure the loads from the descriptor are done after the
MMIO store clearing the interrupts has completed, otherwise we
might still miss work.
A read back from the MMIO register will "push" the posted store and
ioread32 has a barrier on weakly aordered architectures that will
order subsequent accesses.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This uses the standard phy-mode property
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just call the interrupt handler with interrupts locally disabled
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The chip supports HW vlan tag insertion and extraction. Add support
for it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the ndo_set_rx_mode() callback to configure the
multicast filters, promisc and allmulti options.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hopefully my understanding of how the hardware works is correct,
as the documentation isn't completely clear. So far I have seen
no obvious issue. Pause seem to also work with NC-SI.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
A non-wired up implementation accidentally made its way in
a previous patch (Make ring sizes configurable via ethtool).
This removes it and wires up the generic phy_ethtool_nway_reset
instead.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is relatively esoteric, and knowing that we don't have it makes life
easier in some cases rather than just an eventual -EINVAL from
pci_mmap_page_range().
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We can declare it <linux/pci.h> even on platforms where it isn't going to
be defined. There's no need to have it littered through the various
<asm/pci.h> files.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Most of the almost-identical versions of pci_mmap_page_range() silently
ignore the 'write_combine' argument and give uncached mappings.
Yet we allow the PCIIOC_WRITE_COMBINE ioctl in /proc/bus/pci, expose the
'resourceX_wc' file in sysfs, and allow an attempted mapping to apparently
succeed.
To fix this, introduce a macro arch_can_pci_mmap_wc() which indicates
whether the platform can do a write-combining mapping. On x86 this ends up
being pat_enabled(), while the few other platforms that support it can just
set it to a literal '1'.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The /proc/bus/pci mmap interface allows the user to specify whether they
want WC or not. Don't let them do so on non-prefetchable BARs.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Don't match MMIO maps with I/O BARs and vice versa.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Correct some minor errors in the register defaults.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Brian Austin <brian.austin@cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The generic SPI code calculates how long the issued transfer would take
and adds 100ms in addition to the timeout as tolerance. On my 500 MHz
Lantiq Mips SoC I am getting timeouts from the SPI like this when the
system boots up:
m25p80 spi32766.4: SPI transfer timed out
blk_update_request: I/O error, dev mtdblock3, sector 2
SQUASHFS error: squashfs_read_data failed to read block 0x6e
After increasing the tolerance for the timeout to 200ms I haven't seen
these SPI transfer time outs any more.
The Lantiq SPI driver in use here has an extra work queue in between,
which gets triggered when the controller send the last word and the
hardware FIFOs used for reading and writing are only 8 words long.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The workqueue may still be running when the devres callbacks start
firing to deallocate an acpi_nfit_desc instance. Stop and flush the
workqueue before letting any other devres de-allocations proceed.
Reported-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Markus Elfring says:
====================
Ethernet-Marvell: Fine-tuning for several function implementations
Several update suggestions were taken into account
from static source code analysis.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
A string which did not contain a data format specification should be put
into a sequence. Thus use the corresponding function "seq_puts".
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The script "checkpatch.pl" pointed information out like the following.
Comparison to NULL could be written "!skge->mem".
Thus fix the affected source code place.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
A string which did not contain a data format specification should be put
into a sequence. Thus use the corresponding function "seq_puts".
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The script “checkpatch.pl” pointed information out like the following.
Comparison to NULL could be written …
Thus fix the affected source code places.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Multiplications for the size determination of memory allocations
indicated that array data structures should be processed.
Thus use the corresponding function "kcalloc".
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The script "checkpatch.pl" pointed information out like the following.
Comparison to NULL could be written "txq->descs".
Thus fix the affected source code place.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adjust jump labels according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adjust jump labels according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adjust jump labels according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adjust jump labels according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the word "failed" in the string for three function calls.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adjust jump labels according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The script "checkpatch.pl" pointed out that labels should not be indented.
Thus delete two horizontal tabs before the jump label "err_drop_frame"
in the function "mvpp2_rx".
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the specification of two data structures by pointer dereferences
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the specification of data structures by references to
a local variable as the parameter for the operator "sizeof"
to make the corresponding size determination a bit safer.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
