aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlberto Garcia <berto@igalia.com>2015-11-04 15:15:36 +0200
committerKevin Wolf <kwolf@redhat.com>2015-11-11 16:25:47 +0100
commita0d64a61db602696f4f1895a890c65eda5b3b618 (patch)
treea448fb1c4f0a3b60b0fb09f0bd81beab9ef748db
parent5ac724184c286b367525035eabf4b8bb4a386c54 (diff)
downloadqemu-arm-a0d64a61db602696f4f1895a890c65eda5b3b618.tar.gz
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 <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r--block.c6
-rw-r--r--block/qapi.c2
-rw-r--r--blockdev.c4
-rw-r--r--include/block/block_int.h5
4 files changed, 10 insertions, 7 deletions
diff --git a/block.c b/block.c
index 34935015dd..cffac75016 100644
--- a/block.c
+++ b/block.c
@@ -1907,7 +1907,7 @@ void bdrv_close(BlockDriverState *bs)
}
/* Disable I/O limits and drain all pending throttled requests */
- if (bs->io_limits_enabled) {
+ if (bs->throttle_state) {
bdrv_io_limits_disable(bs);
}
@@ -3712,7 +3712,7 @@ void bdrv_detach_aio_context(BlockDriverState *bs)
baf->detach_aio_context(baf->opaque);
}
- if (bs->io_limits_enabled) {
+ if (bs->throttle_state) {
throttle_timers_detach_aio_context(&bs->throttle_timers);
}
if (bs->drv->bdrv_detach_aio_context) {
@@ -3748,7 +3748,7 @@ 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) {
+ if (bs->throttle_state) {
throttle_timers_attach_aio_context(&bs->throttle_timers, new_context);
}
diff --git a/block/qapi.c b/block/qapi.c
index ec0f5139e2..89d4274177 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -64,7 +64,7 @@ BlockDeviceInfo *bdrv_block_device_info(BlockDriverState *bs, Error **errp)
info->backing_file_depth = bdrv_get_backing_file_depth(bs);
info->detect_zeroes = bs->detect_zeroes;
- if (bs->io_limits_enabled) {
+ if (bs->throttle_state) {
ThrottleConfig cfg;
throttle_group_get_config(bs, &cfg);
diff --git a/blockdev.c b/blockdev.c
index 7645d491cb..3598b01419 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2361,14 +2361,14 @@ void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd,
if (throttle_enabled(&cfg)) {
/* Enable I/O limits if they're not enabled yet, otherwise
* just update the throttling group. */
- if (!bs->io_limits_enabled) {
+ if (!bs->throttle_state) {
bdrv_io_limits_enable(bs, has_group ? group : device);
} else if (has_group) {
bdrv_io_limits_update_group(bs, group);
}
/* Set the new throttling configuration */
bdrv_set_io_limits(bs, &cfg);
- } else if (bs->io_limits_enabled) {
+ } else if (bs->throttle_state) {
/* If all throttling settings are set to 0, disable I/O limits */
bdrv_io_limits_disable(bs);
}
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.