[lkml]   [2011]   [Jul]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    Subject[GIT PULL] Lockless SLUB slowpaths for v3.1-rc1
    Hi Linus,

    This pull request has patches to make SLUB slowpaths lockless like we
    already did for the fastpaths. They have been sitting in linux-next for a
    while now and should be fine. David Rientjes reports improved performance:

    I ran slub/lockless through some stress testing and it seems to be quite
    stable on my testing cluster. There is about a 2.3% performance
    improvement with the lockless slowpath on the netperf benchmark with
    various thread counts on my 16-core 64GB Opterons, so I'd recommend it to
    be merged into 3.1.

    One possible gotcha, though, is that page struct gets bigger on x86_64. Hugh
    Dickins writes:

    By the way, if you're thinking of lining up a pull request to Linus
    for 3.1, please make it very clear in that request that these changes
    enlarge the x86_64 struct page from 56 to 64 bytes, for slub alone.

    I remain very uneasy about that (love the cache alignment but...),
    the commit comment is rather vague about it, and I'm not sure that
    anyone else has noticed yet (akpm?).

    Given that Linus wouldn't let Kosaki add 4 bytes to the 32-bit
    vm_area_struct in 3.0, telling him about this upfront does not
    improve your chances that he will pull ;) but does protect you
    from his wrath when he'd later find it sneaked in.

    We haven't come up with a solution to keep struct page size the same but
    I think it's a reasonable trade-off.


    The following changes since commit 95b6886526bb510b8370b625a49bc0ab3b8ff10f:
    Linus Torvalds (1):
    Merge branch 'for-linus' of git://

    are available in the git repository at:

    ssh:// slub/lockless

    Christoph Lameter (20):
    slub: Push irq disable into allocate_slab()
    slub: Do not use frozen page flag but a bit in the page counters
    slub: Move page->frozen handling near where the page->freelist handling occurs
    mm: Rearrange struct page
    slub: Add cmpxchg_double_slab()
    slub: explicit list_lock taking
    slub: Pass kmem_cache struct to lock and freeze slab
    slub: Rework allocator fastpaths
    slub: Invert locking and avoid slab lock
    slub: Disable interrupts in free_debug processing
    slub: Avoid disabling interrupts in free slowpath
    slub: Get rid of the another_slab label
    slub: Add statistics for the case that the current slab does not match the node
    slub: fast release on full slab
    slub: Not necessary to check for empty slab on load_freelist
    slub: slabinfo update for cmpxchg handling
    SLUB: Fix build breakage in linux/mm_types.h
    Avoid duplicate _count variables in page_struct
    slub: disable interrupts in cmpxchg_double_slab when falling back to pagelock
    slub: When allocating a new slab also prep the first object

    Pekka Enberg (2):
    Merge remote branch 'tip/x86/atomic' into slub/lockless
    Revert "SLUB: Fix build breakage in linux/mm_types.h"

    arch/x86/Kconfig.cpu | 3 +
    arch/x86/include/asm/cmpxchg_32.h | 48 +++
    arch/x86/include/asm/cmpxchg_64.h | 45 +++
    arch/x86/include/asm/cpufeature.h | 2 +
    include/linux/mm_types.h | 89 +++--
    include/linux/page-flags.h | 5 -
    include/linux/slub_def.h | 3 +
    mm/slub.c | 764 +++++++++++++++++++++++++------------
    tools/slub/slabinfo.c | 59 ++-
    9 files changed, 714 insertions(+), 304 deletions(-)

     \ /
      Last update: 2011-07-29 00:51    [W:0.022 / U:193.488 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site