1. 09 Jan, 2006 4 commits
  2. 06 Jan, 2006 2 commits
    • Christoph Lameter's avatar
      [PATCH] atomic_long_t & include/asm-generic/atomic.h V2 · d3cb4871
      Christoph Lameter authored
      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: default avatarChristoph Lameter <clameter@sgi.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      d3cb4871
    • Badari Pulavarty's avatar
      [PATCH] madvise(MADV_REMOVE): remove pages from tmpfs shm backing store · f6b3ec23
      Badari Pulavarty authored
      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: default avatarBadari 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: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      f6b3ec23
  3. 03 Jan, 2006 1 commit
  4. 15 Dec, 2005 2 commits
  5. 14 Nov, 2005 2 commits
  6. 07 Nov, 2005 5 commits
  7. 31 Oct, 2005 3 commits
  8. 28 Oct, 2005 1 commit
  9. 05 Oct, 2005 1 commit
  10. 04 Oct, 2005 1 commit
  11. 29 Sep, 2005 1 commit
  12. 21 Sep, 2005 1 commit
    • Paolo 'Blaisorblade' Giarrusso's avatar
      [PATCH] Remove unused var from asm/futex.h · 676067cf
      Paolo 'Blaisorblade' Giarrusso authored
      As recently done by Russell King for ARM, commit
      4732efbe 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 9feff4ce1424bc390608326240be369eb13aa648
      
      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: default avatarPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      676067cf
  13. 10 Sep, 2005 1 commit
    • Ingo Molnar's avatar
      [PATCH] spinlock consolidation · fb1c8f93
      Ingo Molnar authored
      This patch (written by me and also containing many suggestions of Arjan van
      de Ven) does a major cleanup of the spinlock code.  It does the following
      things:
      
       - consolidates and enhances the spinlock/rwlock debugging code
      
       - simplifies the asm/spinlock.h files
      
       - encapsulates the raw spinlock type and moves generic spinlock
         features (such as ->break_lock) into the generic code.
      
       - cleans up the spinlock code hierarchy to get rid of the spaghetti.
      
      Most notably there's now only a single variant of the debugging code,
      located in lib/spinlock_debug.c.  (previously we had one SMP debugging
      variant per architecture, plus a separate generic one for UP builds)
      
      Also, i've enhanced the rwlock debugging facility, it will now track
      write-owners.  There is new spinlock-owner/CPU-tracking on SMP builds too.
      All locks have lockup detection now, which will work for both soft and hard
      spin/rwlock lockups.
      
      The arch-level include files now only contain the minimally necessary
      subset of the spinlock code - all the rest that can be generalized now
      lives in the generic headers:
      
       include/asm-i386/spinlock_types.h       |   16
       include/asm-x86_64/spinlock_types.h     |   16
      
      I have also split up the various spinlock variants into separate files,
      making it easier to see which does what. The new layout is:
      
         SMP                         |  UP
         ----------------------------|-----------------------------------
         asm/spinlock_types_smp.h    |  linux/spinlock_types_up.h
         linux/spinlock_types.h      |  linux/spinlock_types.h
         asm/spinlock_smp.h          |  linux/spinlock_up.h
         linux/spinlock_api_smp.h    |  linux/spinlock_api_up.h
         linux/spinlock.h            |  linux/spinlock.h
      
      /*
       * here's the role of the various spinlock/rwlock related include files:
       *
       * on SMP builds:
       *
       *  asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
       *                        initializers
       *
       *  linux/spinlock_types.h:
       *                        defines the generic type and initializers
       *
       *  asm/spinlock.h:       contains the __raw_spin_*()/etc. lowlevel
       *                        implementations, mostly inline assembly code
       *
       *   (also included on UP-debug builds:)
       *
       *  linux/spinlock_api_smp.h:
       *                        contains the prototypes for the _spin_*() APIs.
       *
       *  linux/spinlock.h:     builds the final spin_*() APIs.
       *
       * on UP builds:
       *
       *  linux/spinlock_type_up.h:
       *                        contains the generic, simplified UP spinlock type.
       *                        (which is an empty structure on non-debug builds)
       *
       *  linux/spinlock_types.h:
       *                        defines the generic type and initializers
       *
       *  linux/spinlock_up.h:
       *                        contains the __raw_spin_*()/etc. version of UP
       *                        builds. (which are NOPs on non-debug, non-preempt
       *                        builds)
       *
       *   (included on UP-non-debug builds:)
       *
       *  linux/spinlock_api_up.h:
       *                        builds the _spin_*() APIs.
       *
       *  linux/spinlock.h:     builds the final spin_*() APIs.
       */
      
      All SMP and UP architectures are converted by this patch.
      
      arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
      crosscompilers.  m32r, mips, sh, sparc, have not been tested yet, but should
      be mostly fine.
      
      From: Grant Grundler <grundler@parisc-linux.org>
      
        Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
        Builds 32-bit SMP kernel (not booted or tested).  I did not try to build
        non-SMP kernels.  That should be trivial to fix up later if necessary.
      
        I converted bit ops atomic_hash lock to raw_spinlock_t.  Doing so avoids
        some ugly nesting of linux/*.h and asm/*.h files.  Those particular locks
        are well tested and contained entirely inside arch specific code.  I do NOT
        expect any new issues to arise with them.
      
       If someone does ever need to use debug/metrics with them, then they will
        need to unravel this hairball between spinlocks, atomic ops, and bit ops
        that exist only because parisc has exactly one atomic instruction: LDCW
        (load and clear word).
      
      From: "Luck, Tony" <tony.luck@intel.com>
      
         ia64 fix
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarArjan van de Ven <arjanv@infradead.org>
      Signed-off-by: default avatarGrant Grundler <grundler@parisc-linux.org>
      Cc: Matthew Wilcox <willy@debian.org>
      Signed-off-by: default avatarHirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: default avatarMikael Pettersson <mikpe@csd.uu.se>
      Signed-off-by: default avatarBenoit Boissinot <benoit.boissinot@ens-lyon.org>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      fb1c8f93
  14. 09 Sep, 2005 1 commit
  15. 07 Sep, 2005 9 commits
    • Stephen Rothwell's avatar
      [PATCH] Clean up struct flock64 definitions · 8d286aa5
      Stephen Rothwell authored
      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: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      8d286aa5
    • Stephen Rothwell's avatar
      [PATCH] Clean up struct flock definitions · 5ac353f9
      Stephen Rothwell authored
      This patch just gathers together all the struct flock definitions except
      xtensa into asm-generic/fcntl.h.
      Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5ac353f9
    • Stephen Rothwell's avatar
      [PATCH] Clean up the fcntl operations · 1abf62af
      Stephen Rothwell authored
      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: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      1abf62af
    • Stephen Rothwell's avatar
      [PATCH] Clean up the open flags · e64ca97f
      Stephen Rothwell authored
      This patch puts the most popular of each open flag into asm-generic/fcntl.h
      and cleans up the arch files.
      Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      e64ca97f
    • Stephen Rothwell's avatar
      [PATCH] Create asm-generic/fcntl.h · 9317259e
      Stephen Rothwell authored
      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: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarYoichi Yuasa <yuasa@hh.iij4u.or.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      9317259e
    • Jesper Juhl's avatar
      [PATCH] remove verify_area(): remove verify_area() from various uaccess.h headers · 97de50c0
      Jesper Juhl authored
      Remove the deprecated (and unused) verify_area() from various uaccess.h
      headers.
      Signed-off-by: default avatarJesper Juhl <jesper.juhl@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      97de50c0
    • Christoph Hellwig's avatar
      [PATCH] remove asm-*/hdreg.h · c8d12741
      Christoph Hellwig authored
      unused and useless..
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      c8d12741
    • H. J. Lu's avatar
      [PATCH] auxiliary vector cleanups · 36d57ac4
      H. J. Lu authored
      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: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      36d57ac4
    • Jakub Jelinek's avatar
      [PATCH] FUTEX_WAKE_OP: pthread_cond_signal() speedup · 4732efbe
      Jakub Jelinek authored
      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: default avatarIngo 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: default avatarYoichi Yuasa <yuasa@hh.iij4u.or.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      4732efbe
  16. 05 Sep, 2005 2 commits
  17. 02 Sep, 2005 1 commit
  18. 29 Aug, 2005 2 commits