[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-block] [PATCH 0/3] coroutine: avoid co_queue_wakeup recursion
From: |
Stefan Hajnoczi |
Subject: |
Re: [Qemu-block] [PATCH 0/3] coroutine: avoid co_queue_wakeup recursion |
Date: |
Tue, 27 Mar 2018 13:11:12 +0100 |
User-agent: |
Mutt/1.9.2 (2017-12-15) |
On Thu, Mar 22, 2018 at 03:28:31PM +0000, Stefan Hajnoczi wrote:
> co_queue_wakeup is currently implemented in a recursive fashion. Pathological
> patterns of aio_co_enter() between coroutines can cause stack exhaustion.
>
> This patch series implements co_queue_wakeup iteratively and avoids stack
> exhaustion.
>
> This issue was originally reported with qemu-img convert but I don't have a
> good reproducer. See Patch 3 for a test-aio test case instead.
>
> Stefan Hajnoczi (3):
> queue: add QSIMPLEQ_PREPEND()
> coroutine: avoid co_queue_wakeup recursion
> coroutine: add test-aio coroutine queue chaining test case
>
> include/qemu/coroutine_int.h | 1 -
> include/qemu/queue.h | 8 ++++
> block/io.c | 3 +-
> tests/test-aio.c | 65 ++++++++++++++++++++-----
> util/qemu-coroutine-lock.c | 34 -------------
> util/qemu-coroutine.c | 110
> +++++++++++++++++++++++--------------------
> 6 files changed, 120 insertions(+), 101 deletions(-)
>
> --
> 2.14.3
>
Thanks, applied to my block tree:
https://github.com/stefanha/qemu/commits/block
Stefan
signature.asc
Description: PGP signature