Am 31.10.2012 16:34, schrieb Stefan Hajnoczi: > AIO control blocks are frequently acquired and released because each aio > request involves at least one AIOCB. Therefore, we pool them to avoid heap > allocation overhead. > > The problem with the freelist approach in AIOPool is thread-safety. If > we want BlockDriverStates to associate with AioContexts that execute in > multiple threads, then a global freelist becomes a problem. > > This patch drops the freelist and instead uses g_slice_alloc() which is > tuned for per-thread fixed-size object pools. qemu_aio_get() and > qemu_aio_release() are now thread-safe. > > Note that the change from g_malloc0() to g_slice_alloc() should be safe > since the freelist reuse case doesn't zero the AIOCB either. > > v2: > * Split into 3 patches (I still took the liberty of combining the AIOPool -> > AIOCBInfo rename with constification because I didn't want to touch all > those files twice) [Paolo] > > Stefan Hajnoczi (3): > aio: switch aiocb_size type int -> size_t > aio: use g_slice_alloc() for AIOCB pooling > aio: rename AIOPool to AIOCBInfo > > block.c | 31 ++++++++++++------------------- > block/blkdebug.c | 4 ++-- > block/blkverify.c | 4 ++-- > block/curl.c | 4 ++-- > block/gluster.c | 6 +++--- > block/iscsi.c | 12 ++++++------ > block/linux-aio.c | 4 ++-- > block/qed.c | 4 ++-- > block/rbd.c | 4 ++-- > block/sheepdog.c | 4 ++-- > block/win32-aio.c | 4 ++-- > dma-helpers.c | 4 ++-- > hw/ide/core.c | 4 ++-- > qemu-aio.h | 12 +++++------- > thread-pool.c | 4 ++-- > 15 files changed, 48 insertions(+), 57 deletions(-)
Thanks, applied all to the block branch. Kevin
