From a0d64a61db602696f4f1895a890c65eda5b3b618 Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Wed, 4 Nov 2015 15:15:36 +0200 Subject: throttle: Use bs->throttle_state instead of bs->io_limits_enabled There are two ways to check for I/O limits in a BlockDriverState: - bs->throttle_state: if this pointer is not NULL, it means that this BDS is member of a throttling group, its ThrottleTimers structure has been initialized and its I/O limits are ready to be applied. - bs->io_limits_enabled: if true it means that the throttle_state pointer is valid _and_ the limits are currently enabled. The latter is used in several places to check whether a BDS has I/O limits configured, but what it really checks is whether requests are being throttled or not. For example, io_limits_enabled can be temporarily set to false in cases like bdrv_read_unthrottled() without otherwise touching the throtting configuration of that BDS. This patch replaces bs->io_limits_enabled with bs->throttle_state in all cases where what we really want to check is the existence of I/O limits, not whether they are currently enabled or not. Signed-off-by: Alberto Garcia Signed-off-by: Kevin Wolf --- include/block/block_int.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/block/block_int.h') diff --git a/include/block/block_int.h b/include/block/block_int.h index 6a3f64da12..603145a21d 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -390,7 +390,10 @@ struct BlockDriverState { /* number of in-flight serialising requests */ unsigned int serialising_in_flight; - /* I/O throttling */ + /* I/O throttling. + * throttle_state tells us if this BDS has I/O limits configured. + * io_limits_enabled tells us if they are currently being + * enforced, but it can be temporarily set to false */ CoQueue throttled_reqs[2]; bool io_limits_enabled; /* The following fields are protected by the ThrottleGroup lock. -- cgit v1.2.3