1. 26 Mar, 2006 5 commits
  2. 25 Mar, 2006 1 commit
    • Davide Libenzi's avatar
      [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications · f348d70a
      Davide Libenzi authored
      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: default avatarDavide Libenzi <[email protected]>
      Cc: "David S. Miller" <[email protected]emloft.net>
      Cc: Michael Kerrisk <[email protected]>
      Signed-off-by: default avatarAndrew Morton <[email protected]>
      Signed-off-by: default avatarLinus Torvalds <[email protected]>
      f348d70a
  3. 24 Mar, 2006 1 commit
  4. 15 Feb, 2006 2 commits
  5. 01 Feb, 2006 6 commits
  6. 17 Jan, 2006 6 commits
  7. 12 Jan, 2006 4 commits
  8. 10 Jan, 2006 1 commit
  9. 09 Jan, 2006 4 commits
  10. 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 <[email protected]>
      Signed-off-by: default avatarAndrew Morton <[email protected]>
      Signed-off-by: default avatarLinus Torvalds <[email protected]>
      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 <[email protected]>
      Cc: Hugh Dickins <[email protected]>
      Cc: Andrea Arcangeli <[email protected]>
      Cc: Michael Kerrisk <[email protected]>
      Cc: Ulrich Drepper <[email protected]>
      Signed-off-by: default avatarAndrew Morton <[email protected]>
      Signed-off-by: default avatarLinus Torvalds <[email protected]>
      f6b3ec23
  11. 03 Jan, 2006 1 commit
  12. 14 Nov, 2005 2 commits
  13. 09 Nov, 2005 1 commit
  14. 07 Nov, 2005 3 commits
  15. 31 Oct, 2005 1 commit