throttle: add throttle_detach/attach_aio_context()

Block I/O throttling uses timers and currently always adds them to the
main loop.  Throttling will break if bdrv_set_aio_context() is used to
move a BlockDriverState to a different AioContext.

This patch adds throttle_detach/attach_aio_context() interfaces so the
throttling timers and uses them to move timers to the new AioContext.
Note that bdrv_set_aio_context() already drains all requests so we're
sure no throttled requests are pending.

The test cases need to be updated since the throttle_init() interface
has changed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
This commit is contained in:
Stefan Hajnoczi 2014-05-14 16:22:45 +02:00
parent c9f87b20b9
commit 13af91ebf0
4 changed files with 60 additions and 9 deletions

View file

@ -179,6 +179,7 @@ void bdrv_io_limits_enable(BlockDriverState *bs)
{
assert(!bs->io_limits_enabled);
throttle_init(&bs->throttle_state,
bdrv_get_aio_context(bs),
QEMU_CLOCK_VIRTUAL,
bdrv_throttle_read_timer_cb,
bdrv_throttle_write_timer_cb,
@ -5671,6 +5672,9 @@ void bdrv_detach_aio_context(BlockDriverState *bs)
return;
}
if (bs->io_limits_enabled) {
throttle_detach_aio_context(&bs->throttle_state);
}
if (bs->drv->bdrv_detach_aio_context) {
bs->drv->bdrv_detach_aio_context(bs);
}
@ -5702,6 +5706,9 @@ void bdrv_attach_aio_context(BlockDriverState *bs,
if (bs->drv->bdrv_attach_aio_context) {
bs->drv->bdrv_attach_aio_context(bs, new_context);
}
if (bs->io_limits_enabled) {
throttle_attach_aio_context(&bs->throttle_state, new_context);
}
}
void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context)