1
Commit Graph

60 Commits

Author SHA1 Message Date
KAMEZAWA Hiroyuki
bb872f787a [PATCH] unify pfn_to_page: cris pfn_to_page
cris can use generic funcs.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:45 -08:00
Akinobu Mita
e9f26df172 [PATCH] bitops: cris: use generic bitops
- remove __{,test_and_}{set,clear,change}_bit() and test_bit()
- remove generic_fls()
- remove generic_fls64()
- remove generic_hweight{32,16,8}()
- remove find_{next,first}{,_zero}_bit()
- remove ext2_{set,clear,test,find_first_zero,find_next_zero}_bit()
- remove minix_{test,set,test_and_clear,test,find_first_zero}_bit()
- remove sched_find_first_bit()

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Acked-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:12 -08:00
Akinobu Mita
67b0ad574b [PATCH] bitops: use non atomic operations for minix_*_bit() and ext2_*_bit()
Bitmap functions for the minix filesystem and the ext2 filesystem except
ext2_set_bit_atomic() and ext2_clear_bit_atomic() do not require the atomic
guarantees.

But these are defined by using atomic bit operations on several architectures.
 (cris, frv, h8300, ia64, m32r, m68k, m68knommu, mips, s390, sh, sh64, sparc,
sparc64, v850, and xtensa)

This patch switches to non atomic bit operation.

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:10 -08:00
Akinobu Mita
72b61a3cfd [PATCH] bitops: cris: remove unnecessary local_irq_restore()
remove unnecessary local_irq_restore() after cris_atomic_restore() in
test_and_set_bit().

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:10 -08:00
Davide Libenzi
f348d70a32 [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications
Implement the half-closed devices notifiation, by adding a new POLLRDHUP
(and its alias EPOLLRDHUP) bit to the existing poll/select sets.  Since the
existing POLLHUP handling, that does not report correctly half-closed
devices, was feared to be changed, this implementation leaves the current
POLLHUP reporting unchanged and simply add a new bit that is set in the few
places where it makes sense.  The same thing was discussed and conceptually
agreed quite some time ago:

http://lkml.org/lkml/2003/7/12/116

Since this new event bit is added to the existing Linux poll infrastruture,
even the existing poll/select system calls will be able to use it.  As far
as the existing POLLHUP handling, the patch leaves it as is.  The
pollrdhup-2.6.16.rc5-0.10.diff defines the POLLRDHUP for all the existing
archs and sets the bit in the six relevant files.  The other attached diff
is the simple change required to sys/epoll.h to add the EPOLLRDHUP
definition.

There is "a stupid program" to test POLLRDHUP delivery here:

 http://www.xmailserver.org/pollrdhup-test.c

It tests poll(2), but since the delivery is same epoll(2) will work equally.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:56 -08:00
Adrian Bunk
cdb0452789 [PATCH] kill include/linux/platform.h, default_idle() cleanup
include/linux/platform.h contained nothing that was actually used except
the default_idle() prototype, and is therefore removed by this patch.

This patch does the following with the platform specific default_idle()
functions on different architectures:
- remove the unused function:
  - parisc
  - sparc64
- make the needlessly global function static:
  - arm
  - h8300
  - m68k
  - m68knommu
  - s390
  - v850
  - x86_64
- add a prototype in asm/system.h:
  - cris
  - i386
  - ia64

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Patrick Mochel <mochel@digitalimplant.org>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:21 -08:00
Michael S. Tsirkin
5f6164f309 [PATCH] add asm-generic/mman.h
Make new MADV_REMOVE, MADV_DONTFORK, MADV_DOFORK consistent across all
arches.  The idea is to make it possible to use them portably even before
distros include them in libc headers.

Move common flags to asm-generic/mman.h

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-15 15:32:22 -08:00
Michael S. Tsirkin
f822566165 [PATCH] madvise MADV_DONTFORK/MADV_DOFORK
Currently, copy-on-write may change the physical address of a page even if the
user requested that the page is pinned in memory (either by mlock or by
get_user_pages).  This happens if the process forks meanwhile, and the parent
writes to that page.  As a result, the page is orphaned: in case of
get_user_pages, the application will never see any data hardware DMA's into
this page after the COW.  In case of mlock'd memory, the parent is not getting
the realtime/security benefits of mlock.

In particular, this affects the Infiniband modules which do DMA from and into
user pages all the time.

This patch adds madvise options to control whether memory range is inherited
across fork.  Useful e.g.  for when hardware is doing DMA from/into these
pages.  Could also be useful to an application wanting to speed up its forks
by cutting large areas out of consideration.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:34 -08:00
Alexey Dobriyan
bcc68b8616 [PATCH] include/asm-*/bitops.h: fix more "~0UL >> size" typos
"[PATCH] m68knommu: fix find_next_zero_bit in bitops.h" fixed a typo in
m68knommu implementation of find_next_zero_bit().

grep(1) shows that cris, frv, h8300, v850 are also affected.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:02 -08:00
Al Viro
f5a61d0c13 [PATCH] death of get_thread_info/put_thread_info
{get,put}_thread_info() were introduced in 2.5.4 and never
had been called by anything in the tree.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:59 -08:00
Al Viro
cfa0f29b6d [PATCH] cris: fix KSTK_EIP
cris KSTK_EIP looked for pt_regs at the right offset but from the wrong
place - forgotten ->thread_info

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:58 -08:00
Al Viro
95ca0dc603 [PATCH] cris: task_pt_regs()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:58 -08:00
Brian Gerst
af4cd3fe4c [PATCH] Generic ioctl.h
Most arches copied the i386 ioctl.h.  Combine them into a generic header.

Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:34 -08:00
Arjan van de Ven
2acbb8c657 [PATCH] mutex subsystem, add default include/asm-*/mutex.h files
add the per-arch mutex.h files for the remaining architectures.

We default to asm-generic/mutex-dec.h, because that performs
quite well on most arches. Arches that do not have atomic
decrement/increment instructions should switch to mutex-xchg.h
instead. Arches can also provide their own implementation for
the mutex fastpath primitives.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:19 -08:00
Ingo Molnar
ffbf670f5c [PATCH] mutex subsystem, add atomic_xchg() to all arches
add atomic_xchg() to all the architectures. Needed by the new mutex code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
2006-01-09 15:59:17 -08:00
Jeff Dike
f8aaeacec1 [PATCH] consolidate asm/futex.h
Most of the architectures have the same asm/futex.h.  This consolidates them
into asm-generic, with the arches including it from their own asm/futex.h.

In the case of UML, this reverts the old broken futex.h and goes back to using
the same one as almost everyone else.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Ravikiran G Thirumalai
1fd73c6b67 [PATCH] Kill L1_CACHE_SHIFT_MAX
Kill L1_CACHE_SHIFT from all arches.  Since L1_CACHE_SHIFT_MAX is not used
anymore with the introduction of INTERNODE_CACHE, kill L1_CACHE_SHIFT_MAX.

Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Christoph Lameter
d3cb487149 [PATCH] atomic_long_t & include/asm-generic/atomic.h V2
Several counters already have the need to use 64 atomic variables on 64 bit
platforms (see mm_counter_t in sched.h).  We have to do ugly ifdefs to fall
back to 32 bit atomic on 32 bit platforms.

The VM statistics patch that I am working on will also make more extensive
use of atomic64.

This patch introduces a new type atomic_long_t by providing definitions in
asm-generic/atomic.h that works similar to the c "long" type.  Its 32 bits
on 32 bit platforms and 64 bits on 64 bit platforms.

Also cleans up the determination of the mm_counter_t in sched.h.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:29 -08:00
Badari Pulavarty
f6b3ec238d [PATCH] madvise(MADV_REMOVE): remove pages from tmpfs shm backing store
Here is the patch to implement madvise(MADV_REMOVE) - which frees up a
given range of pages & its associated backing store.  Current
implementation supports only shmfs/tmpfs and other filesystems return
-ENOSYS.

"Some app allocates large tmpfs files, then when some task quits and some
client disconnect, some memory can be released.  However the only way to
release tmpfs-swap is to MADV_REMOVE". - Andrea Arcangeli

Databases want to use this feature to drop a section of their bufferpool
(shared memory segments) - without writing back to disk/swap space.

This feature is also useful for supporting hot-plug memory on UML.

Concerns raised by Andrew Morton:

- "We have no plan for holepunching!  If we _do_ have such a plan (or
  might in the future) then what would the API look like?  I think
  sys_holepunch(fd, start, len), so we should start out with that."

- Using madvise is very weird, because people will ask "why do I need to
  mmap my file before I can stick a hole in it?"

- None of the other madvise operations call into the filesystem in this
  manner.  A broad question is: is this capability an MM operation or a
  filesytem operation?  truncate, for example, is a filesystem operation
  which sometimes has MM side-effects.  madvise is an mm operation and with
  this patch, it gains FS side-effects, only they're really, really
  significant ones."

Comments:

- Andrea suggested the fs operation too but then it's more efficient to
  have it as a mm operation with fs side effects, because they don't
  immediatly know fd and physical offset of the range.  It's possible to
  fixup in userland and to use the fs operation but it's more expensive,
  the vmas are already in the kernel and we can use them.

Short term plan &  Future Direction:

- We seem to need this interface only for shmfs/tmpfs files in the short
  term.  We have to add hooks into the filesystem for correctness and
  completeness.  This is what this patch does.

- In the future, plan is to support both fs and mmap apis also.  This
  also involves (other) filesystem specific functions to be implemented.

- Current patch doesn't support VM_NONLINEAR - which can be addressed in
  the future.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrea Arcangeli <andrea@suse.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Stephen Hemminger
3821af2fe1 [FLS64]: generic version
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03 13:11:06 -08:00
Nick Piggin
8426e1f6af [PATCH] atomic: inc_not_zero
Introduce an atomic_inc_not_zero operation.  Make this a special case of
atomic_add_unless because lockless pagecache actually wants
atomic_inc_not_negativeone due to its offset refcount.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:16 -08:00
Nick Piggin
4a6dae6d38 [PATCH] atomic: cmpxchg
Introduce an atomic_cmpxchg operation.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:16 -08:00
Tim Schmielau
8c65b4a604 [PATCH] fix remaining missing includes
Fix more include file problems that surfaced since I submitted the previous
fix-missing-includes.patch.  This should now allow not to include sched.h
from module.h, which is done by a followup patch.

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:41 -08:00
Adrian Bunk
d9b5444eeb [PATCH] cris: "extern inline" -> "static inline"
"extern inline" doesn't make much sense.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:30 -08:00
Arthur Othieno
5f9c3cbcd5 [PATCH] cris: printk() duplicate declaration
printk() already declared in include/linux/kernel.h so squish the
duplication.  Besides, no printk() usage here.  Bye bye.

Signed-off-by: Arthur Othieno <a.othieno@bluewin.ch>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:30 -08:00
Arthur Othieno
727a53bd53 [PATCH] semaphore: Remove __MUTEX_INITIALIZER()
__MUTEX_INITIALIZER() has no users, and equates to the more commonly used
DECLARE_MUTEX(), thus making it pretty much redundant.  Remove it for good.

Signed-off-by: Arthur Othieno <a.othieno@bluewin.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:27 -08:00
Christoph Hellwig
dfb7dac3af [PATCH] unify sys_ptrace prototype
Make sure we always return, as all syscalls should.  Also move the common
prototype to <linux/syscalls.h>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:20 -08:00
Al Viro
43b7eae1f5 [PATCH] gfp_t: dma-mapping (cris)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:48 -07:00
Paolo 'Blaisorblade' Giarrusso
676067cfea [PATCH] Remove unused var from asm/futex.h
As recently done by Russell King for ARM, commit
4732efbeb9 introduces a generic asm/futex.h copied
along most arches, which includes a "-ENOSYS support" to be changed if needed.
However, it includes an unused var (taken from the "real" version) which GCC
warns about.

Remove it from all arches having that file version (i.e. same GIT id).
$ git-diff-tree -r HEAD
and
$ git-ls-tree  -r HEAD include/|grep 9feff4ce14

may be more interesting than looking at the patch itself, to make sure I've
just copied the arm header to all other archs having the original dummy version
of this file.

Cc: Jakub Jelinek <jakub@redhat.com>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:29 -07:00
Stephen Rothwell
8d286aa5ea [PATCH] Clean up struct flock64 definitions
This patch gathers all the struct flock64 definitions (and the operations),
puts them under !CONFIG_64BIT and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
5ac353f9ba [PATCH] Clean up struct flock definitions
This patch just gathers together all the struct flock definitions except
xtensa into asm-generic/fcntl.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
1abf62afb6 [PATCH] Clean up the fcntl operations
This patch puts the most popular of each fcntl operation/flag into
asm-generic/fcntl.h and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
e64ca97fd8 [PATCH] Clean up the open flags
This patch puts the most popular of each open flag into asm-generic/fcntl.h
and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
9317259ead [PATCH] Create asm-generic/fcntl.h
This set of patches creates asm-generic/fcntl.h and consolidates as much as
possible from the asm-*/fcntl.h files into it.

This patch just gathers all the identical bits of the asm-*/fcntl.h files into
asm-generic/fcntl.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:37 -07:00
Jesper Juhl
97de50c0ad [PATCH] remove verify_area(): remove verify_area() from various uaccess.h headers
Remove the deprecated (and unused) verify_area() from various uaccess.h
headers.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:35 -07:00
Karsten Wiese
f26fdd5992 [PATCH] CHECK_IRQ_PER_CPU() to avoid dead code in __do_IRQ()
IRQ_PER_CPU is not used by all architectures.  This patch introduces the
macros ARCH_HAS_IRQ_PER_CPU and CHECK_IRQ_PER_CPU() to avoid the generation
of dead code in __do_IRQ().

ARCH_HAS_IRQ_PER_CPU is defined by architectures using IRQ_PER_CPU in their
include/asm_ARCH/irq.h file.

Through grepping the tree I found the following architectures currently use
IRQ_PER_CPU:

        cris, ia64, ppc, ppc64 and parisc.

Signed-off-by: Karsten Wiese <annabellesgarden@yahoo.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:29 -07:00
H. J. Lu
36d57ac4a8 [PATCH] auxiliary vector cleanups
The size of auxiliary vector is fixed at 42 in linux/sched.h.  But it isn't
very obvious when looking at linux/elf.h.  This patch adds AT_VECTOR_SIZE
so that we can change it if necessary when a new vector is added.

Because of include file ordering problems, doing this necessitated the
extraction of the AT_* symbols into a standalone header file.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:21 -07:00
Jakub Jelinek
4732efbeb9 [PATCH] FUTEX_WAKE_OP: pthread_cond_signal() speedup
ATM pthread_cond_signal is unnecessarily slow, because it wakes one waiter
(which at least on UP usually means an immediate context switch to one of
the waiter threads).  This waiter wakes up and after a few instructions it
attempts to acquire the cv internal lock, but that lock is still held by
the thread calling pthread_cond_signal.  So it goes to sleep and eventually
the signalling thread is scheduled in, unlocks the internal lock and wakes
the waiter again.

Now, before 2003-09-21 NPTL was using FUTEX_REQUEUE in pthread_cond_signal
to avoid this performance issue, but it was removed when locks were
redesigned to the 3 state scheme (unlocked, locked uncontended, locked
contended).

Following scenario shows why simply using FUTEX_REQUEUE in
pthread_cond_signal together with using lll_mutex_unlock_force in place of
lll_mutex_unlock is not enough and probably why it has been disabled at
that time:

The number is value in cv->__data.__lock.
        thr1            thr2            thr3
0       pthread_cond_wait
1       lll_mutex_lock (cv->__data.__lock)
0       lll_mutex_unlock (cv->__data.__lock)
0       lll_futex_wait (&cv->__data.__futex, futexval)
0                       pthread_cond_signal
1                       lll_mutex_lock (cv->__data.__lock)
1                                       pthread_cond_signal
2                                       lll_mutex_lock (cv->__data.__lock)
2                                         lll_futex_wait (&cv->__data.__lock, 2)
2                       lll_futex_requeue (&cv->__data.__futex, 0, 1, &cv->__data.__lock)
                          # FUTEX_REQUEUE, not FUTEX_CMP_REQUEUE
2                       lll_mutex_unlock_force (cv->__data.__lock)
0                         cv->__data.__lock = 0
0                         lll_futex_wake (&cv->__data.__lock, 1)
1       lll_mutex_lock (cv->__data.__lock)
0       lll_mutex_unlock (cv->__data.__lock)
          # Here, lll_mutex_unlock doesn't know there are threads waiting
          # on the internal cv's lock

Now, I believe it is possible to use FUTEX_REQUEUE in pthread_cond_signal,
but it will cost us not one, but 2 extra syscalls and, what's worse, one of
these extra syscalls will be done for every single waiting loop in
pthread_cond_*wait.

We would need to use lll_mutex_unlock_force in pthread_cond_signal after
requeue and lll_mutex_cond_lock in pthread_cond_*wait after lll_futex_wait.

Another alternative is to do the unlocking pthread_cond_signal needs to do
(the lock can't be unlocked before lll_futex_wake, as that is racy) in the
kernel.

I have implemented both variants, futex-requeue-glibc.patch is the first
one and futex-wake_op{,-glibc}.patch is the unlocking inside of the kernel.
 The kernel interface allows userland to specify how exactly an unlocking
operation should look like (some atomic arithmetic operation with optional
constant argument and comparison of the previous futex value with another
constant).

It has been implemented just for ppc*, x86_64 and i?86, for other
architectures I'm including just a stub header which can be used as a
starting point by maintainers to write support for their arches and ATM
will just return -ENOSYS for FUTEX_WAKE_OP.  The requeue patch has been
(lightly) tested just on x86_64, the wake_op patch on ppc64 kernel running
32-bit and 64-bit NPTL and x86_64 kernel running 32-bit and 64-bit NPTL.

With the following benchmark on UP x86-64 I get:

for i in nptl-orig nptl-requeue nptl-wake_op; do echo time elf/ld.so --library-path .:$i /tmp/bench; \
for j in 1 2; do echo ( time elf/ld.so --library-path .:$i /tmp/bench ) 2>&1; done; done
time elf/ld.so --library-path .:nptl-orig /tmp/bench
real 0m0.655s user 0m0.253s sys 0m0.403s
real 0m0.657s user 0m0.269s sys 0m0.388s
time elf/ld.so --library-path .:nptl-requeue /tmp/bench
real 0m0.496s user 0m0.225s sys 0m0.271s
real 0m0.531s user 0m0.242s sys 0m0.288s
time elf/ld.so --library-path .:nptl-wake_op /tmp/bench
real 0m0.380s user 0m0.176s sys 0m0.204s
real 0m0.382s user 0m0.175s sys 0m0.207s

The benchmark is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00001.txt
Older futex-requeue-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00002.txt
Older futex-wake_op-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00003.txt
Will post a new version (just x86-64 fixes so that the patch
applies against pthread_cond_signal.S) to libc-hacker ml soon.

Attached is the kernel FUTEX_WAKE_OP patch as well as a simple-minded
testcase that will not test the atomicity of the operation, but at least
check if the threads that should have been woken up are woken up and
whether the arithmetic operation in the kernel gave the expected results.

Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Jamie Lokier <jamie@shareable.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:17 -07:00
Kyle Moffett
fa5b08d5f8 [PATCH] sab: consolidate kmem_bufctl_t
This is used only in slab.c and each architecture gets to define whcih
underlying type is to be used.

Seems a bit silly - move it to slab.c and use the same type for all
architectures: unsigned int.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:48 -07:00
Stephen Rothwell
fd4fd5aac1 [PATCH] mm: consolidate get_order
Someone mentioned that almost all the architectures used basically the same
implementation of get_order.  This patch consolidates them into
asm-generic/page.h and includes that in the appropriate places.  The
exceptions are ia64 and ppc which have their own (presumably optimised)
versions.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:39 -07:00
Patrick McHardy
b0573dea1f [NET]: Introduce SO_{SND,RCV}BUFFORCE socket options
Allows overriding of sysctl_{wmem,rmrm}_max

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:31:35 -07:00
Mikael Starvik
51533b615e [PATCH] CRIS update: new subarchitecture v32
New CRIS sub architecture named v32.

From: Dave Jones <davej@redhat.com>

	Fix swapped kmalloc args

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:01 -07:00
Mikael Starvik
5d01e6ce78 [PATCH] CRIS update: updates for 2.6.12
Patches to make CRIS work with 2.6.12.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:01 -07:00
Mikael Starvik
dcf1310b72 [PATCH] CRIS update: synchronous serial port driver
Include file for synchronous serial port driver.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:01 -07:00
Mikael Starvik
8d20a541b0 [PATCH] CRIS update: SMP
Patches to support SMP.

* Each CPU has its own current_pgd.
* flush_tlb_range is implemented as flush_tlb_mm.
* Atomic operations implemented with spinlocks.
* Semaphores implemented with spinlocks.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:01 -07:00
Mikael Starvik
21783c9746 [PATCH] CRIS update: profiler
System-level profiler.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:00 -07:00
Mikael Starvik
59c61138a5 [PATCH] CRIS update: pci
Patches to make it possible to add PCI support.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:00 -07:00
Mikael Starvik
4f18cfbf09 [PATCH] CRIS update: mm
Memory management patches.

* SMP support.
* Non-executable stack (on v32).
* 4-level page tables.
* Added simple Thread Local Storage support.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:00 -07:00
Mikael Starvik
7cf32cad15 [PATCH] CRIS update: misc patches
* Start threads with IRQs enabled.
* Move symbol exports to arch specific file.
* Prepare for real command line in the future.
* Handle csum for partition that crosses flash boundary.
* Set utsname.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:00 -07:00
Mikael Starvik
2e0cea1dec [PATCH] CRIS update: IRQ
Use the generic IRQ framework

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:00 -07:00