[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v3 5/5] block-coroutine-wrapper: use qemu_get_current_aio_context
From: |
Stefan Hajnoczi |
Subject: |
[PATCH v3 5/5] block-coroutine-wrapper: use qemu_get_current_aio_context() |
Date: |
Tue, 12 Sep 2023 19:10:37 -0400 |
Use qemu_get_current_aio_context() in mixed wrappers and coroutine
wrappers so that code runs in the caller's AioContext instead of moving
to the BlockDriverState's AioContext. This change is necessary for the
multi-queue block layer where any thread can call into the block layer.
Most wrappers are IO_CODE where it's safe to use the current AioContext
nowadays. BlockDrivers and the core block layer use their own locks and
no longer depend on the AioContext lock for thread-safety.
The bdrv_create() wrapper invokes GLOBAL_STATE code. Using the current
AioContext is safe because this code is only called with the BQL held
from the main loop thread.
The output of qemu-iotests 051 is sensitive to event loop activity.
Update the output because the monitor BH runs at a different time,
causing prompts to be printed differently in the output.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
scripts/block-coroutine-wrapper.py | 6 ++----
tests/qemu-iotests/051.pc.out | 4 ++--
2 files changed, 4 insertions(+), 6 deletions(-)
diff --git a/scripts/block-coroutine-wrapper.py
b/scripts/block-coroutine-wrapper.py
index d4a183db61..f93fe154c3 100644
--- a/scripts/block-coroutine-wrapper.py
+++ b/scripts/block-coroutine-wrapper.py
@@ -88,8 +88,6 @@ def __init__(self, wrapper_type: str, return_type: str, name:
str,
raise ValueError(f"no_co function can't be rdlock:
{self.name}")
self.target_name = f'{subsystem}_{subname}'
- self.ctx = self.gen_ctx()
-
self.get_result = 's->ret = '
self.ret = 'return s.ret;'
self.co_ret = 'return '
@@ -162,7 +160,7 @@ def create_mixed_wrapper(func: FuncDecl) -> str:
{func.co_ret}{name}({ func.gen_list('{name}') });
}} else {{
{struct_name} s = {{
- .poll_state.ctx = {func.ctx},
+ .poll_state.ctx = qemu_get_current_aio_context(),
.poll_state.in_progress = true,
{ func.gen_block(' .{name} = {name},') }
@@ -186,7 +184,7 @@ def create_co_wrapper(func: FuncDecl) -> str:
{func.return_type} {func.name}({ func.gen_list('{decl}') })
{{
{struct_name} s = {{
- .poll_state.ctx = {func.ctx},
+ .poll_state.ctx = qemu_get_current_aio_context(),
.poll_state.in_progress = true,
{ func.gen_block(' .{name} = {name},') }
diff --git a/tests/qemu-iotests/051.pc.out b/tests/qemu-iotests/051.pc.out
index 4d4af5a486..650cfed8e2 100644
--- a/tests/qemu-iotests/051.pc.out
+++ b/tests/qemu-iotests/051.pc.out
@@ -177,11 +177,11 @@ QEMU_PROG: -device virtio-blk-pci,drive=disk,share-rw=on:
Cannot change iothread
Testing: -drive file=TEST_DIR/t.qcow2,if=none,node-name=disk -object
iothread,id=thread0 -device virtio-scsi,iothread=thread0,id=virtio-scsi0
-device scsi-hd,bus=virtio-scsi0.0,drive=disk,share-rw=on -device
lsi53c895a,id=lsi0 -device scsi-hd,bus=lsi0.0,drive=disk,share-rw=on
QEMU X.Y.Z monitor - type 'help' for more information
-(qemu) QEMU_PROG: -device scsi-hd,bus=lsi0.0,drive=disk,share-rw=on: HBA does
not support iothreads
+QEMU_PROG: -device scsi-hd,bus=lsi0.0,drive=disk,share-rw=on: HBA does not
support iothreads
Testing: -drive file=TEST_DIR/t.qcow2,if=none,node-name=disk -object
iothread,id=thread0 -device virtio-scsi,iothread=thread0,id=virtio-scsi0
-device scsi-hd,bus=virtio-scsi0.0,drive=disk,share-rw=on -device
virtio-scsi,id=virtio-scsi1 -device
scsi-hd,bus=virtio-scsi1.0,drive=disk,share-rw=on
QEMU X.Y.Z monitor - type 'help' for more information
-(qemu) QEMU_PROG: -device scsi-hd,bus=virtio-scsi1.0,drive=disk,share-rw=on:
Cannot change iothread of active block backend
+QEMU_PROG: -device scsi-hd,bus=virtio-scsi1.0,drive=disk,share-rw=on: Cannot
change iothread of active block backend
Testing: -drive file=TEST_DIR/t.qcow2,if=none,node-name=disk -object
iothread,id=thread0 -device virtio-scsi,iothread=thread0,id=virtio-scsi0
-device scsi-hd,bus=virtio-scsi0.0,drive=disk,share-rw=on -device
virtio-blk-pci,drive=disk,iothread=thread0,share-rw=on
QEMU X.Y.Z monitor - type 'help' for more information
--
2.41.0
- [PATCH v3 1/5] block: remove AIOCBInfo->get_aio_context(), (continued)
- [PATCH v3 1/5] block: remove AIOCBInfo->get_aio_context(), Stefan Hajnoczi, 2023/09/12
- [PATCH v3 2/5] test-bdrv-drain: avoid race with BH in IOThread drain test, Stefan Hajnoczi, 2023/09/12
- [PATCH v3 3/5] block-backend: process I/O in the current AioContext, Stefan Hajnoczi, 2023/09/12
- [PATCH v3 4/5] block-backend: process zoned requests in the current AioContext, Stefan Hajnoczi, 2023/09/12
- [PATCH v3 5/5] block-coroutine-wrapper: use qemu_get_current_aio_context(),
Stefan Hajnoczi <=
- Re: [PATCH v3 0/5] block-backend: process I/O in the current AioContext, Kevin Wolf, 2023/09/15