linux-stable.git/arch/xtensa/include/asm, branch v4.8

Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-07-25T19:41:29+00:00

Pull locking updates from Ingo Molnar:
 "The locking tree was busier in this cycle than the usual pattern - a
  couple of major projects happened to coincide.

  The main changes are:

   - implement the atomic_fetch_{add,sub,and,or,xor}() API natively
     across all SMP architectures (Peter Zijlstra)

   - add atomic_fetch_{inc/dec}() as well, using the generic primitives
     (Davidlohr Bueso)

   - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
     Waiman Long)

   - optimize smp_cond_load_acquire() on arm64 and implement LSE based
     atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
     on arm64 (Will Deacon)

   - introduce smp_acquire__after_ctrl_dep() and fix various barrier
     mis-uses and bugs (Peter Zijlstra)

   - after discovering ancient spin_unlock_wait() barrier bugs in its
     implementation and usage, strengthen its semantics and update/fix
     usage sites (Peter Zijlstra)

   - optimize mutex_trylock() fastpath (Peter Zijlstra)

   - ... misc fixes and cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
  locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
  locking/static_keys: Fix non static symbol Sparse warning
  locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
  locking/atomic, arch/tile: Fix tilepro build
  locking/atomic, arch/m68k: Remove comment
  locking/atomic, arch/arc: Fix build
  locking/Documentation: Clarify limited control-dependency scope
  locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
  locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
  locking/atomic, arch/mips: Convert to _relaxed atomics
  locking/atomic, arch/alpha: Convert to _relaxed atomics
  locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
  locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
  locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
  locking/atomic: Fix atomic64_relaxed() bits
  locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  ...

tree wide: get rid of __GFP_REPEAT for order-0 allocations part I

2016-06-25T00:23:52+00:00

This is the third version of the patchset previously sent [1].  I have
basically only rebased it on top of 4.7-rc1 tree and dropped "dm: get
rid of superfluous gfp flags" which went through dm tree.  I am sending
it now because it is tree wide and chances for conflicts are reduced
considerably when we want to target rc2.  I plan to send the next step
and rename the flag and move to a better semantic later during this
release cycle so we will have a new semantic ready for 4.8 merge window
hopefully.

Motivation:

While working on something unrelated I've checked the current usage of
__GFP_REPEAT in the tree.  It seems that a majority of the usage is and
always has been bogus because __GFP_REPEAT has always been about costly
high order allocations while we are using it for order-0 or very small
orders very often.  It seems that a big pile of them is just a
copy&paste when a code has been adopted from one arch to another.

I think it makes some sense to get rid of them because they are just
making the semantic more unclear.  Please note that GFP_REPEAT is
documented as

* __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt

* _might_ fail.  This depends upon the particular VM implementation.
  while !costly requests have basically nofail semantic.  So one could
  reasonably expect that order-0 request with __GFP_REPEAT will not loop
  for ever.  This is not implemented right now though.

I would like to move on with __GFP_REPEAT and define a better semantic
for it.

  $ git grep __GFP_REPEAT origin/master | wc -l
  111
  $ git grep __GFP_REPEAT | wc -l
  36

So we are down to the third after this patch series.  The remaining
places really seem to be relying on __GFP_REPEAT due to large allocation
requests.  This still needs some double checking which I will do later
after all the simple ones are sorted out.

I am touching a lot of arch specific code here and I hope I got it right
but as a matter of fact I even didn't compile test for some archs as I
do not have cross compiler for them.  Patches should be quite trivial to
review for stupid compile mistakes though.  The tricky parts are usually
hidden by macro definitions and thats where I would appreciate help from
arch maintainers.

[1] http://lkml.kernel.org/r/1461849846-27209-1-git-send-email-mhocko@kernel.org

This patch (of 19):

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.  Yet we
have the full kernel tree with its usage for apparently order-0
allocations.  This is really confusing because __GFP_REPEAT is
explicitly documented to allow allocation failures which is a weaker
semantic than the current order-0 has (basically nofail).

Let's simply drop __GFP_REPEAT from those places.  This would allow to
identify place which really need allocator to retry harder and formulate
a more specific semantic for what the flag is supposed to do actually.

Link: http://lkml.kernel.org/r/1464599699-30131-2-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Cc: "David S. Miller" 
Cc: "H. Peter Anvin" 
Cc: "James E.J. Bottomley" 
Cc: "Theodore Ts'o" 
Cc: Andy Lutomirski 
Cc: Benjamin Herrenschmidt 
Cc: Catalin Marinas 
Cc: Chen Liqin 
Cc: Chris Metcalf  [for tile]
Cc: Guan Xuetao 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Ingo Molnar 
Cc: Jan Kara 
Cc: John Crispin 
Cc: Lennox Wu 
Cc: Ley Foon Tan 
Cc: Martin Schwidefsky 
Cc: Matt Fleming 
Cc: Ralf Baechle 
Cc: Rich Felker 
Cc: Russell King 
Cc: Thomas Gleixner 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

locking/atomic: Remove linux/atomic.h:atomic_fetch_or()

2016-06-16T08:48:32+00:00

Since all architectures have this implemented now natively, remove this
dead code.

Signed-off-by: Peter Zijlstra (Intel) 
Cc: Andrew Morton 
Cc: Linus Torvalds 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()

2016-06-16T08:48:31+00:00

Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).

Signed-off-by: Peter Zijlstra (Intel) 
Cc: Andrew Morton 
Cc: Chris Zankel 
Cc: Linus Torvalds 
Cc: Max Filippov 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Ingo Molnar

locking/spinlock, arch: Update and fix spin_unlock_wait() implementations

2016-06-14T09:55:15+00:00

This patch updates/fixes all spin_unlock_wait() implementations.

The update is in semantics; where it previously was only a control
dependency, we now upgrade to a full load-acquire to match the
store-release from the spin_unlock() we waited on. This ensures that
when spin_unlock_wait() returns, we're guaranteed to observe the full
critical section we waited on.

This fixes a number of spin_unlock_wait() users that (not
unreasonably) rely on this.

I also fixed a number of ticket lock versions to only wait on the
current lock holder, instead of for a full unlock, as this is
sufficient.

Furthermore; again for ticket locks; I added an smp_rmb() in between
the initial ticket load and the spin loop testing the current value
because I could not convince myself the address dependency is
sufficient, esp. if the loads are of different sizes.

I'm more than happy to remove this smp_rmb() again if people are
certain the address dependency does indeed work as expected.

Note: PPC32 will be fixed independently

Signed-off-by: Peter Zijlstra (Intel) 
Cc: Andrew Morton 
Cc: Linus Torvalds 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: chris@zankel.net
Cc: cmetcalf@mellanox.com
Cc: davem@davemloft.net
Cc: dhowells@redhat.com
Cc: james.hogan@imgtec.com
Cc: jejb@parisc-linux.org
Cc: linux@armlinux.org.uk
Cc: mpe@ellerman.id.au
Cc: ralf@linux-mips.org
Cc: realmz6@gmail.com
Cc: rkuo@codeaurora.org
Cc: rth@twiddle.net
Cc: schwidefsky@de.ibm.com
Cc: tony.luck@intel.com
Cc: vgupta@synopsys.com
Cc: ysato@users.sourceforge.jp
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

locking/rwsem, xtensa: Drop superfluous arch specific implementation

2016-04-13T08:42:18+00:00

Since "locking, rwsem: drop explicit memory barriers" the arch specific
code is basically same as the the generic one so we can drop the
superfluous code.

Suggested-by: Davidlohr Bueso 
Signed-off-by: Michal Hocko 
Acked-by: Max Filippov 
Cc: Andrew Morton 
Cc: Chris Zankel 
Cc: David S. Miller 
Cc: Linus Torvalds 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Signed-off-by: Davidlohr Bueso 
Cc: Signed-off-by: Jason Low 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1460041951-22347-4-git-send-email-mhocko@kernel.org
Signed-off-by: Ingo Molnar

locking/rwsem: Drop explicit memory barriers

2016-04-13T08:42:18+00:00

sh and xtensa seem to be the only architectures which use explicit
memory barriers for rw_semaphore operations even though they are not
really needed because there is the full memory barrier is always implied
by atomic_{inc,dec,add,sub}_return() resp. cmpxchg(). Remove them.

Signed-off-by: Michal Hocko 
Cc: Andrew Morton 
Cc: Chris Zankel 
Cc: David S. Miller 
Cc: Linus Torvalds 
Cc: Max Filippov 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Signed-off-by: Davidlohr Bueso 
Cc: Signed-off-by: Jason Low 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1460041951-22347-3-git-send-email-mhocko@kernel.org
Signed-off-by: Ingo Molnar

Merge tag 'xtensa-next-20160320' of git://github.com/czankel/xtensa-linux

2016-03-20T19:22:07+00:00

Pull Xtensa updates from Chris Zankel:
 "Xtensa improvements for 4.6:

   - control whether perf IRQ is treated as NMI from Kconfig
   - implement ioremap for regions outside KIO segment
   - fix ISS serial port behaviour when EOF is reached
   - fix preemption in {clear,copy}_user_highpage
   - fix endianness issues for XTFPGA devices, big-endian cores are now
     fully functional
   - clean up debug infrastructure and add support for hardware
     breakpoints and watchpoints
   - add processor configurations for Three Core HiFi-2 MX and HiFi3
     cpus"

* tag 'xtensa-next-20160320' of git://github.com/czankel/xtensa-linux:
  xtensa: add test_kc705_hifi variant
  xtensa: add Three Core HiFi-2 MX Variant.
  xtensa: support hardware breakpoints/watchpoints
  xtensa: use context structure for debug exceptions
  xtensa: remove remaining non-functional KGDB bits
  xtensa: clear all DBREAKC registers on start
  xtensa: xtfpga: fix earlycon endianness
  xtensa: xtfpga: fix i2c controller register width and endianness
  xtensa: xtfpga: fix ethernet controller endianness
  xtensa: xtfpga: fix serial port register width and endianness
  xtensa: define CONFIG_CPU_{BIG,LITTLE}_ENDIAN
  xtensa: fix preemption in {clear,copy}_user_highpage
  xtensa: ISS: don't hang if stdin EOF is reached
  xtensa: support ioremap for memory outside KIO region
  xtensa: use XTENSA_INT_LEVEL macro in asm/timex.h
  xtensa: make fake NMI configurable

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2016-03-19T17:05:34+00:00

Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...

Merge tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

2016-03-18T04:05:32+00:00

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for kernel v4.6.  There is quite a
  lot of interesting stuff going on.

  The patches to other subsystems and arch-wide are ACKed as far as
  possible, though I consider things like per-arch  as
  essentially a part of the GPIO subsystem so it should not be needed.

  Core changes:

   - The gpio_chip is now a *real device*.  Until now the gpio chips
     were just piggybacking the parent device or (gasp) floating in
     space outside of the device model.

     We now finally make GPIO chips devices.  The gpio_chip will create
     a gpio_device which contains a struct device, and this gpio_device
     struct is kept private.  Anything that needs to be kept private
     from the rest of the kernel will gradually be moved over to the
     gpio_device.

   - As a result of making the gpio_device a real device, we have added
     resource management, so devm_gpiochip_add_data() will cut down on
     overhead and reduce code lines.  A huge slew of patches convert
     almost all drivers in the subsystem to use this.

   - Building on making the GPIO a real device, we add the first step of
     a new userspace ABI: the GPIO character device.  We take small
     steps here, so we first add a pure *information* ABI and the tool
     "lsgpio" that will list all GPIO devices on the system and all
     lines on these devices.

     We can now discover GPIOs properly from userspace.  We still have
     not come up with a way to actually *use* GPIOs from userspace.

   - To encourage people to use the character device for the future, we
     have it always-enabled when using GPIO.  The old sysfs ABI is still
     opt-in (and can be used in parallel), but is marked as deprecated.

     We will keep it around for the foreseeable future, but it will not
     be extended to cover ever more use cases.

  Cleanup:

   - Bjorn Helgaas removed a whole slew of per-architecture 
     includes.

     This dates back to when GPIO was an opt-in feature and no shared
     library even existed: just a header file with proper prototypes was
     provided and all semantics were up to the arch to implement.  These
     patches make the GPIO chip even more a proper device and cleans out
     leftovers of the old in-kernel API here and there.

     Still some cruft is left but it's very little now.

   - There is still some clamping of return values for .get() going on,
     but we now return sane values in the vast majority of drivers and
     the errorpath is sanitized.  Some patches for powerpc, blackfin and
     unicore still drop in.

   - We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
     implementations to use gpiochip_add_data() and cut down on code
     lines.

   - MPC8xxx is converted to use the generic GPIO helpers.

   - ATH79 is converted to use the generic GPIO helpers.

  New drivers:

   - WinSystems WS16C48

   - Acces 104-DIO-48E

   - F81866 (a F7188x variant)

   - Qoric (a MPC8xxx variant)

   - TS-4800

   - SPI serializers (pisosr): simple 74xx shift registers connected to
     SPI to obtain a dirt-cheap output-only GPIO expander.

   - Texas Instruments TPIC2810

   - Texas Instruments TPS65218

   - Texas Instruments TPS65912

   - X-Gene (ARM64) standby GPIO controller"

* tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (194 commits)
  Revert "Share upstreaming patches"
  gpio: mcp23s08: Fix clearing of interrupt.
  gpiolib: Fix comment referring to gpio_*() in gpiod_*()
  gpio: pca953x: Fix pca953x_gpio_set_multiple() on 64-bit
  gpio: xgene: Fix kconfig for standby GIPO contoller
  gpio: Add generic serializer DT binding
  gpio: uapi: use 0xB4 as ioctl() major
  gpio: tps65912: fix bad merge
  Revert "gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free"
  gpio: omap: drop dev field from gpio_bank structure
  gpio: mpc8xxx: Slightly update the code for better readability
  gpio: mpc8xxx: Remove *read_reg and *write_reg from struct mpc8xxx_gpio_chip
  gpio: mpc8xxx: Fixup setting gpio direction output
  gpio: mcp23s08: Add support for mcp23s18
  dt-bindings: gpio: altera: Fix altr,interrupt-type property
  gpio: add driver for MEN 16Z127 GPIO controller
  gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free
  gpio: timberdale: Switch to devm_ioremap_resource()
  gpio: ts4800: Add IMX51 dependency
  gpiolib: rewrite gpiodev_add_to_list
  ...