On 08/06/2017 14:52, Stefan Hajnoczi wrote:
> On Wed, May 31, 2017 at 11:43:19AM +0200, Paolo Bonzini wrote:
>> This part takes care of drivers and devices, making sure that they can
>> accept concurrent I/O from multiple AioContext. Only RFC for now because it
>> depends on Kevin's QED conversion to coroutines, which is still in flux.
>>
>> The following drivers are thread-safe without using any QemuMutex/CoMutex:
>> crypto, gluster, null, rbd, win32-aio.
>>
>> The following drivers already use mutexes for everything except possibly
>> snapshots, which do not (yet?) need protection: bochs, cloop, dmg, qcow,
>> parallels, vhdx, vmdk, curl, iscsi, nfs.
>>
>> The following drivers already use mutexes for _almost_ everything: vpc
>> (missing get_block_status), vdi (missing bitmap access), vvfat (missing
>> commit), nbd (s->in_flight not protected), qcow2 (must call CoQueue APIs
>> under CoMutex). They are fixed by patches 1-6.
>>
>> The following drivers must be changed to use CoMutex to protect internal
>> data: qed (patches 7-9), sheepdog (patch 10).
>>
>> The following driver must be changed to support I/O from any AioContext:
>> ssh. It is fixed by patch 11.
>>
>> Paolo
>>
>> Paolo Bonzini (11):
>> qcow2: call CoQueue APIs under CoMutex
>> coroutine-lock: add qemu_co_rwlock_downgrade and qemu_co_rwlock_upgrade
>> vdi: make it thread-safe
>> vpc: make it thread-safe
>> vvfat: make it thread-safe
>> nbd: make it thread-safe
>> qed: move tail of qed_aio_write_main to qed_aio_write_{cow,alloc}
>> block: invoke .bdrv_drain callback in coroutine context and from AioContext
>> qed: protect table cache with CoMutex
>> sheepdog: add queue_lock
>> ssh: support I/O from any AioContext
>>
>> block/io.c | 42 +++++++---
>> block/nbd-client.c | 30 +++----
>> block/qcow2.c | 4 +-
>> block/qed-cluster.c | 4 +-
>> block/qed-l2-cache.c | 6 ++
>> block/qed-table.c | 24 ++++--
>> block/qed.c | 195 +++++++++++++++++++++++++++------------------
>> block/qed.h | 11 ++-
>> block/sheepdog.c | 21 ++++-
>> block/ssh.c | 24 ++++--
>> block/vdi.c | 48 +++++------
>> block/vpc.c | 20 ++---
>> block/vvfat.c | 8 +-
>> include/block/block_int.h | 2 +-
>> include/qemu/coroutine.h | 19 +++++
>> util/qemu-coroutine-lock.c | 35 ++++++++
>> 16 files changed, 326 insertions(+), 167 deletions(-)
>>
>> --
>> 2.13.0
>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Thanks, I'll repost once QED is converted to coroutines, and send part 3
when I have some time.
Paolo