linux/include/asm-sparc64
Ingo Molnar e9056f13bf [PATCH] lightweight robust futexes: arch defaults
This patchset provides a new (written from scratch) implementation of robust
futexes, called "lightweight robust futexes".  We believe this new
implementation is faster and simpler than the vma-based robust futex solutions
presented before, and we'd like this patchset to be adopted in the upstream
kernel.  This is version 1 of the patchset.

  Background
  ----------

What are robust futexes?  To answer that, we first need to understand what
futexes are: normal futexes are special types of locks that in the
noncontended case can be acquired/released from userspace without having to
enter the kernel.

A futex is in essence a user-space address, e.g.  a 32-bit lock variable
field.  If userspace notices contention (the lock is already owned and someone
else wants to grab it too) then the lock is marked with a value that says
"there's a waiter pending", and the sys_futex(FUTEX_WAIT) syscall is used to
wait for the other guy to release it.  The kernel creates a 'futex queue'
internally, so that it can later on match up the waiter with the waker -
without them having to know about each other.  When the owner thread releases
the futex, it notices (via the variable value) that there were waiter(s)
pending, and does the sys_futex(FUTEX_WAKE) syscall to wake them up.  Once all
waiters have taken and released the lock, the futex is again back to
'uncontended' state, and there's no in-kernel state associated with it.  The
kernel completely forgets that there ever was a futex at that address.  This
method makes futexes very lightweight and scalable.

"Robustness" is about dealing with crashes while holding a lock: if a process
exits prematurely while holding a pthread_mutex_t lock that is also shared
with some other process (e.g.  yum segfaults while holding a pthread_mutex_t,
or yum is kill -9-ed), then waiters for that lock need to be notified that the
last owner of the lock exited in some irregular way.

To solve such types of problems, "robust mutex" userspace APIs were created:
pthread_mutex_lock() returns an error value if the owner exits prematurely -
and the new owner can decide whether the data protected by the lock can be
recovered safely.

There is a big conceptual problem with futex based mutexes though: it is the
kernel that destroys the owner task (e.g.  due to a SEGFAULT), but the kernel
cannot help with the cleanup: if there is no 'futex queue' (and in most cases
there is none, futexes being fast lightweight locks) then the kernel has no
information to clean up after the held lock!  Userspace has no chance to clean
up after the lock either - userspace is the one that crashes, so it has no
opportunity to clean up.  Catch-22.

In practice, when e.g.  yum is kill -9-ed (or segfaults), a system reboot is
needed to release that futex based lock.  This is one of the leading
bugreports against yum.

To solve this problem, 'Robust Futex' patches were created and presented on
lkml: the one written by Todd Kneisel and David Singleton is the most advanced
at the moment.  These patches all tried to extend the futex abstraction by
registering futex-based locks in the kernel - and thus give the kernel a
chance to clean up.

E.g.  in David Singleton's robust-futex-6.patch, there are 3 new syscall
variants to sys_futex(): FUTEX_REGISTER, FUTEX_DEREGISTER and FUTEX_RECOVER.
The kernel attaches such robust futexes to vmas (via
vma->vm_file->f_mapping->robust_head), and at do_exit() time, all vmas are
searched to see whether they have a robust_head set.

Lots of work went into the vma-based robust-futex patch, and recently it has
improved significantly, but unfortunately it still has two fundamental
problems left:

 - they have quite complex locking and race scenarios.  The vma-based
   patches had been pending for years, but they are still not completely
   reliable.

 - they have to scan _every_ vma at sys_exit() time, per thread!

The second disadvantage is a real killer: pthread_exit() takes around 1
microsecond on Linux, but with thousands (or tens of thousands) of vmas every
pthread_exit() takes a millisecond or more, also totally destroying the CPU's
L1 and L2 caches!

This is very much noticeable even for normal process sys_exit_group() calls:
the kernel has to do the vma scanning unconditionally!  (this is because the
kernel has no knowledge about how many robust futexes there are to be cleaned
up, because a robust futex might have been registered in another task, and the
futex variable might have been simply mmap()-ed into this process's address
space).

This huge overhead forced the creation of CONFIG_FUTEX_ROBUST, but worse than
that: the overhead makes robust futexes impractical for any type of generic
Linux distribution.

So it became clear to us, something had to be done.  Last week, when Thomas
Gleixner tried to fix up the vma-based robust futex patch in the -rt tree, he
found a handful of new races and we were talking about it and were analyzing
the situation.  At that point a fundamentally different solution occured to
me.  This patchset (written in the past couple of days) implements that new
solution.  Be warned though - the patchset does things we normally dont do in
Linux, so some might find the approach disturbing.  Parental advice
recommended ;-)

  New approach to robust futexes
  ------------------------------

At the heart of this new approach there is a per-thread private list of robust
locks that userspace is holding (maintained by glibc) - which userspace list
is registered with the kernel via a new syscall [this registration happens at
most once per thread lifetime].  At do_exit() time, the kernel checks this
user-space list: are there any robust futex locks to be cleaned up?

In the common case, at do_exit() time, there is no list registered, so the
cost of robust futexes is just a simple current->robust_list != NULL
comparison.  If the thread has registered a list, then normally the list is
empty.  If the thread/process crashed or terminated in some incorrect way then
the list might be non-empty: in this case the kernel carefully walks the list
[not trusting it], and marks all locks that are owned by this thread with the
FUTEX_OWNER_DEAD bit, and wakes up one waiter (if any).

The list is guaranteed to be private and per-thread, so it's lockless.  There
is one race possible though: since adding to and removing from the list is
done after the futex is acquired by glibc, there is a few instructions window
for the thread (or process) to die there, leaving the futex hung.  To protect
against this possibility, userspace (glibc) also maintains a simple per-thread
'list_op_pending' field, to allow the kernel to clean up if the thread dies
after acquiring the lock, but just before it could have added itself to the
list.  Glibc sets this list_op_pending field before it tries to acquire the
futex, and clears it after the list-add (or list-remove) has finished.

That's all that is needed - all the rest of robust-futex cleanup is done in
userspace [just like with the previous patches].

Ulrich Drepper has implemented the necessary glibc support for this new
mechanism, which fully enables robust mutexes.  (Ulrich plans to commit these
changes to glibc-HEAD later today.)

Key differences of this userspace-list based approach, compared to the vma
based method:

 - it's much, much faster: at thread exit time, there's no need to loop
   over every vma (!), which the VM-based method has to do.  Only a very
   simple 'is the list empty' op is done.

 - no VM changes are needed - 'struct address_space' is left alone.

 - no registration of individual locks is needed: robust mutexes dont need
   any extra per-lock syscalls.  Robust mutexes thus become a very lightweight
   primitive - so they dont force the application designer to do a hard choice
   between performance and robustness - robust mutexes are just as fast.

 - no per-lock kernel allocation happens.

 - no resource limits are needed.

 - no kernel-space recovery call (FUTEX_RECOVER) is needed.

 - the implementation and the locking is "obvious", and there are no
   interactions with the VM.

  Performance
  -----------

I have benchmarked the time needed for the kernel to process a list of 1
million (!) held locks, using the new method [on a 2GHz CPU]:

 - with FUTEX_WAIT set [contended mutex]: 130 msecs
 - without FUTEX_WAIT set [uncontended mutex]: 30 msecs

I have also measured an approach where glibc does the lock notification [which
it currently does for !pshared robust mutexes], and that took 256 msecs -
clearly slower, due to the 1 million FUTEX_WAKE syscalls userspace had to do.

(1 million held locks are unheard of - we expect at most a handful of locks to
be held at a time.  Nevertheless it's nice to know that this approach scales
nicely.)

  Implementation details
  ----------------------

The patch adds two new syscalls: one to register the userspace list, and one
to query the registered list pointer:

 asmlinkage long
 sys_set_robust_list(struct robust_list_head __user *head,
                     size_t len);

 asmlinkage long
 sys_get_robust_list(int pid, struct robust_list_head __user **head_ptr,
                     size_t __user *len_ptr);

List registration is very fast: the pointer is simply stored in
current->robust_list.  [Note that in the future, if robust futexes become
widespread, we could extend sys_clone() to register a robust-list head for new
threads, without the need of another syscall.]

So there is virtually zero overhead for tasks not using robust futexes, and
even for robust futex users, there is only one extra syscall per thread
lifetime, and the cleanup operation, if it happens, is fast and
straightforward.  The kernel doesnt have any internal distinction between
robust and normal futexes.

If a futex is found to be held at exit time, the kernel sets the highest bit
of the futex word:

	#define FUTEX_OWNER_DIED        0x40000000

and wakes up the next futex waiter (if any). User-space does the rest of
the cleanup.

Otherwise, robust futexes are acquired by glibc by putting the TID into the
futex field atomically.  Waiters set the FUTEX_WAITERS bit:

	#define FUTEX_WAITERS           0x80000000

and the remaining bits are for the TID.

  Testing, architecture support
  -----------------------------

I've tested the new syscalls on x86 and x86_64, and have made sure the parsing
of the userspace list is robust [ ;-) ] even if the list is deliberately
corrupted.

i386 and x86_64 syscalls are wired up at the moment, and Ulrich has tested the
new glibc code (on x86_64 and i386), and it works for his robust-mutex
testcases.

All other architectures should build just fine too - but they wont have the
new syscalls yet.

Architectures need to implement the new futex_atomic_cmpxchg_inuser() inline
function before writing up the syscalls (that function returns -ENOSYS right
now).

This patch:

Add placeholder futex_atomic_cmpxchg_inuser() implementations to every
architecture that supports futexes.  It returns -ENOSYS.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Acked-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:49 -08:00
..
a.out.h [SPARC64]: Increase top of 32-bit process stack. 2006-03-20 01:16:36 -08:00
agp.h [PATCH] AGP fix for Xen VMM 2005-06-07 12:35:43 -07:00
apb.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
asi.h [SPARC64]: Sun4v specific ASI defines. 2006-03-20 01:11:43 -08:00
atomic.h [PATCH] atomic: add_unless cmpxchg optimise 2006-03-23 07:38:17 -08:00
auxio.h [SPARC64]: Get rid of fast IRQ feature. 2005-06-27 17:04:45 -07:00
auxvec.h [PATCH] auxiliary vector cleanups 2005-09-07 16:57:21 -07:00
bbc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
bitops.h [PATCH] bitops: sparc64: use generic bitops 2006-03-26 08:57:14 -08:00
bpp.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
bsderrno.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
bug.h [PATCH] remove all kernel BUGs 2005-05-01 08:59:01 -07:00
bugs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
byteorder.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cache.h [PATCH] Move read_mostly definition to asm/cache.h 2006-03-23 07:38:10 -08:00
cacheflush.h [SPARC64]: Add CONFIG_DEBUG_PAGEALLOC support. 2005-09-25 16:46:57 -07:00
chafsr.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
checksum.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
chmctrl.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cmt.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
compat.h [PATCH] compat: be more consistent about [ug]id_t 2005-09-07 16:57:19 -07:00
const.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cpudata.h [SPARC64]: Add a secondary TSB for hugepage mappings. 2006-03-22 01:15:14 -08:00
cputime.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
current.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dcr.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dcu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
delay.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
display7seg.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
div64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dma-mapping.h [PATCH] gfp_t: dma-mapping (simple cases) 2005-10-28 08:16:49 -07:00
dma.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ebus.h [SPARC]: More abstractions and cleanups of dma handling in cs4231. 2005-11-07 14:09:19 -08:00
elf.h [SPARC64]: Add HWCAP_SPARC_BLKINIT elf capability flag for Niagara. 2006-03-20 01:13:26 -08:00
emergency-restart.h [PATCH] Add emergency_restart() 2005-07-26 14:35:41 -07:00
envctrl.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
errno.h [PATCH] add EOWNERDEAD and ENOTRECOVERABLE version 2 2005-05-01 08:59:06 -07:00
estate.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fbio.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fcntl.h [PATCH] Clean up struct flock definitions 2005-09-07 16:57:38 -07:00
fhc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
floppy.h [SPARC64]: Get rid of fast IRQ feature. 2005-06-27 17:04:45 -07:00
fpumacro.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
futex.h [PATCH] lightweight robust futexes: arch defaults 2006-03-27 08:44:49 -08:00
hardirq.h [SPARC64]: Eliminate irq_cpustat_t. 2005-08-29 22:46:43 -07:00
head.h [SPARC64]: Add GET_GL_GLOBAL() macro for SUN4V. 2006-03-20 01:13:18 -08:00
hw_irq.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
hypervisor.h [SPARC64]: Fix bugs in SUN4V cpu mondo dispatch. 2006-03-20 01:14:09 -08:00
ide.h [SPARC64]: Move DCACHE_ALIASING_POSSIBLE define to asm/page.h 2005-09-19 20:11:57 -07:00
idprom.h [SPARC]: Clean up idprom header files. 2006-03-20 01:12:08 -08:00
intr_queue.h [SPARC64]: Sun4v interrupt queue register definitions. 2006-03-20 01:11:44 -08:00
io.h [SPARC64]: Use 'unsigned long' for port argument to I/O string ops. 2005-08-31 15:01:33 -07:00
ioctl.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ioctls.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
iommu.h [SPARC64]: Fix streaming buffer flushing on PCI and SBUS. 2005-05-31 16:57:59 -07:00
ipc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ipcbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
irq.h [SPARC64]: Fix uniprocessor IRQ targetting on SUN4V. 2006-03-20 01:13:24 -08:00
isa.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
kdebug.h [PATCH] RCU: clean up a few remaining synchronize_kernel() calls 2005-06-25 16:24:38 -07:00
kmap_types.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
kprobes.h [PATCH] kprobes: fix build breakage 2006-01-10 08:01:40 -08:00
linkage.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
local.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
lsu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mc146818rtc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mman.h [PATCH] add asm-generic/mman.h 2006-02-15 15:32:22 -08:00
mmu_context.h [SPARC64]: Add a secondary TSB for hugepage mappings. 2006-03-22 01:15:14 -08:00
mmu.h [SPARC64]: Add a secondary TSB for hugepage mappings. 2006-03-22 01:15:14 -08:00
module.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mostek.h [PATCH] mostek bogus sparse annotations fixed 2005-04-24 12:28:36 -07:00
msgbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mutex.h [PATCH] mutex subsystem, add default include/asm-*/mutex.h files 2006-01-09 15:59:19 -08:00
namei.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ns87303.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
numnodes.h [SPARC64]: Move over to sparsemem. 2006-03-20 01:14:22 -08:00
openprom.h [SPARC64]: Rewrite convoluted physical memory probing. 2005-09-29 17:58:26 -07:00
openpromio.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
oplib.h [SPARC64]: Fix system type in /proc/cpuinfo and remove bogus OBP check. 2006-03-20 01:14:25 -08:00
page.h [PATCH] unify pfn_to_page: generic functions 2006-03-27 08:44:44 -08:00
param.h [SPARC64]: Support CONFIG_HZ 2005-07-08 15:21:51 -07:00
parport.h [SPARC64]: Fix enable_dma() in asm-sparc64/parport.h 2005-07-06 15:41:54 -07:00
pbm.h [SPARC64]: More SUN4V PCI controller work. 2006-03-20 01:12:11 -08:00
pci.h [SPARC64]: Beginnings of SUN4V PCI controller support. 2006-03-20 01:12:10 -08:00
pconf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
percpu.h [PATCH] more for_each_cpu() conversions 2006-03-23 07:38:17 -08:00
perfctr.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pgalloc.h [SPARC64]: Kill pgtable quicklists and use SLAB. 2006-03-20 01:11:14 -08:00
pgtable.h [SPARC64]: Add a secondary TSB for hugepage mappings. 2006-03-22 01:15:14 -08:00
pil.h [SPARC64]: Fix new context version SMP handling. 2006-03-20 01:14:21 -08:00
poll.h [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications 2006-03-25 08:22:56 -08:00
posix_types.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
processor.h [SPARC64]: Top-down address space allocation for 32-bit tasks. 2006-03-20 01:16:35 -08:00
psrcompat.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pstate.h [SPARC64]: Fixup TSTATE layout diagram in asm/pstate.h 2006-03-20 01:13:02 -08:00
ptrace.h [PATCH] consolidate sys_ptrace() 2005-11-07 07:53:42 -08:00
reg.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
resource.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
rtc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
rwsem-const.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
rwsem.h [PATCH] add sem_is_read/write_locked() 2005-10-29 21:40:35 -07:00
sbus.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
scatterlist.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
scratchpad.h [SPARC64]: Sun4v scratchpad register layout. 2006-03-20 01:11:44 -08:00
seccomp.h [SPARC64]: Add missing asm-sparc64/seccomp.h file. 2005-07-11 13:44:56 -07:00
sections.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
semaphore.h [PATCH] semaphore: Remove __MUTEX_INITIALIZER() 2005-10-30 17:37:27 -08:00
sembuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
setup.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sfafsr.h [SPARC64]: Revamp Spitfire error trap handling. 2005-08-29 12:45:11 -07:00
sfp-machine.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
shmbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
shmparam.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigcontext.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
siginfo.h [PATCH] consolidate SIGEV_PAD_SIZE 2005-05-01 08:59:08 -07:00
signal.h [SPARC64]: Add support for IRQ pre-handlers. 2005-07-04 13:24:38 -07:00
smp.h [SPARC64]: Add SMT scheduling support for Niagara. 2006-03-20 01:14:24 -08:00
socket.h [NET]: Introduce SO_{SND,RCV}BUFFORCE socket options 2005-08-29 15:31:35 -07:00
sockios.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
solerrno.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sparsemem.h [SPARC64]: Move over to sparsemem. 2006-03-20 01:14:22 -08:00
spinlock_types.h [PATCH] spinlock consolidation 2005-09-10 10:06:21 -07:00
spinlock.h [SPARC64]: Implement __raw_read_trylock() 2006-01-23 21:03:56 -08:00
spitfire.h [SPARC64]: Add 'hypervisor' to ultra_tlb_type enumeration. 2006-03-20 01:11:39 -08:00
starfire.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
stat.h [PATCH] sparc64: Fix stat 2005-04-18 15:13:15 -07:00
statfs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
string.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sunbpp.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
svr4.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
system.h [SPARC64]: Kill all %pstate changes in context switch code. 2006-03-20 01:11:49 -08:00
termbits.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
termios.h [SPARC]: remove duplicate TIOCPKT_ definitions 2005-11-07 14:10:42 -08:00
thread_info.h [SPARC64]: Correctable ECC errors cannot occur at trap level > 0. 2006-03-20 01:11:33 -08:00
timer.h [SPARC64]: Privatize sun5_timer. 2005-07-24 19:36:13 -07:00
timex.h [SPARC64]: Define ARCH_HAS_READ_CURRENT_TIMER. 2006-03-20 01:13:29 -08:00
tlb.h [SPARC64] mm: simpler tlb_flush_mmu 2005-11-07 14:12:08 -08:00
tlbflush.h [SPARC64]: Move away from virtual page tables, part 1. 2006-03-20 01:11:13 -08:00
topology.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
tsb.h [SPARC64]: Create a seperate kernel TSB for 4MB/256MB mappings. 2006-03-20 01:13:56 -08:00
ttable.h [SPARC64]: More TLB/TSB handling fixes. 2006-03-20 01:13:34 -08:00
types.h [PATCH] sab: consolidate kmem_bufctl_t 2005-09-05 00:05:48 -07:00
uaccess.h [SPARC64]: __bzero_noasi --> __clear_user 2006-03-20 01:13:28 -08:00
uctx.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
unaligned.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
unistd.h [SPARC]: sys_newfstatat --> sys_fstatat64 2006-02-12 23:30:11 -08:00
upa.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
user.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
utrap.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
vdev.h [SPARC64]: Decode virtual-devices interrupts correctly. 2006-03-20 01:13:05 -08:00
vga.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
visasm.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
watchdog.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
xor.h [SPARC64]: Niagara optimized XOR functions for RAID. 2006-03-20 01:14:03 -08:00