xemu-project/xemu
1
0
Fork 0
mirror of https://github.com/xemu-project/xemu.git synced 2024-12-24 04:46:05 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
8e8555a38d
xemu/block/block-copy.c
Paolo Bonzini 4951967d84 ratelimit: protect with a mutex 
Right now, rate limiting is protected by the AioContext mutex, which is
taken for example both by the block jobs and by qmp_block_job_set_speed
(via find_block_job).

We would like to remove the dependency of block layer code on the
AioContext mutex, since most drivers and the core I/O code are already
not relying on it.  However, there is no existing lock that can easily
be taken by both ratelimit_set_speed and ratelimit_calculate_delay,
especially because the latter might run in coroutine context (and
therefore under a CoMutex) but the former will not.

Since concurrent calls to ratelimit_calculate_delay are not possible,
one idea could be to use a seqlock to get a snapshot of slice_ns and
slice_quota.  But for now keep it simple, and just add a mutex to the
RateLimit struct; block jobs are generally not performance critical to
the point of optimizing the clock cycles spent in synchronization.

This also requires the introduction of init/destroy functions, so
add them to the two users of ratelimit.h.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-04 14:15:35 +02:00

842 lines
24 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* block_copy API
*
* Copyright (C) 2013 Proxmox Server Solutions
* Copyright (c) 2019 Virtuozzo International GmbH.
*
* Authors:
* Dietmar Maurer (dietmar@proxmox.com)
* Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "trace.h"
#include "qapi/error.h"
#include "block/block-copy.h"
#include "sysemu/block-backend.h"
#include "qemu/units.h"
#include "qemu/coroutine.h"
#include "block/aio_task.h"
#define BLOCK_COPY_MAX_COPY_RANGE (16 * MiB)
#define BLOCK_COPY_MAX_BUFFER (1 * MiB)
#define BLOCK_COPY_MAX_MEM (128 * MiB)
#define BLOCK_COPY_MAX_WORKERS 64
#define BLOCK_COPY_SLICE_TIME 100000000ULL /* ns */
static coroutine_fn int block_copy_task_entry(AioTask *task);
typedef struct BlockCopyCallState {
/* IN parameters. Initialized in block_copy_async() and never changed. */
BlockCopyState *s;
int64_t offset;
int64_t bytes;
int max_workers;
int64_t max_chunk;
bool ignore_ratelimit;
BlockCopyAsyncCallbackFunc cb;
void *cb_opaque;
/* Coroutine where async block-copy is running */
Coroutine *co;
/* To reference all call states from BlockCopyState */
QLIST_ENTRY(BlockCopyCallState) list;
/* State */
int ret;
bool finished;
QemuCoSleepState *sleep_state;
bool cancelled;
/* OUT parameters */
bool error_is_read;
} BlockCopyCallState;
typedef struct BlockCopyTask {
AioTask task;
BlockCopyState *s;
BlockCopyCallState *call_state;
int64_t offset;
int64_t bytes;
bool zeroes;
QLIST_ENTRY(BlockCopyTask) list;
CoQueue wait_queue; /* coroutines blocked on this task */
} BlockCopyTask;
static int64_t task_end(BlockCopyTask *task)
{
return task->offset + task->bytes;
}
typedef struct BlockCopyState {
/*
* BdrvChild objects are not owned or managed by block-copy. They are
* provided by block-copy user and user is responsible for appropriate
* permissions on these children.
*/
BdrvChild *source;
BdrvChild *target;
BdrvDirtyBitmap *copy_bitmap;
int64_t in_flight_bytes;
int64_t cluster_size;
bool use_copy_range;
int64_t copy_size;
uint64_t len;
QLIST_HEAD(, BlockCopyTask) tasks; /* All tasks from all block-copy calls */
QLIST_HEAD(, BlockCopyCallState) calls;
BdrvRequestFlags write_flags;
/*
* skip_unallocated:
*
* Used by sync=top jobs, which first scan the source node for unallocated
* areas and clear them in the copy_bitmap. During this process, the bitmap
* is thus not fully initialized: It may still have bits set for areas that
* are unallocated and should actually not be copied.
*
* This is indicated by skip_unallocated.
*
* In this case, block_copy() will query the source’s allocation status,
* skip unallocated regions, clear them in the copy_bitmap, and invoke
* block_copy_reset_unallocated() every time it does.
*/
bool skip_unallocated;
ProgressMeter *progress;
SharedResource *mem;
uint64_t speed;
RateLimit rate_limit;
} BlockCopyState;
static BlockCopyTask *find_conflicting_task(BlockCopyState *s,
int64_t offset, int64_t bytes)
{
BlockCopyTask *t;
QLIST_FOREACH(t, &s->tasks, list) {
if (offset + bytes > t->offset && offset < t->offset + t->bytes) {
return t;
}
}
return NULL;
}
/*
* If there are no intersecting tasks return false. Otherwise, wait for the
* first found intersecting tasks to finish and return true.
*/
static bool coroutine_fn block_copy_wait_one(BlockCopyState *s, int64_t offset,
int64_t bytes)
{
BlockCopyTask *task = find_conflicting_task(s, offset, bytes);
if (!task) {
return false;
}
qemu_co_queue_wait(&task->wait_queue, NULL);
return true;
}
/*
* Search for the first dirty area in offset/bytes range and create task at
* the beginning of it.
*/
static BlockCopyTask *block_copy_task_create(BlockCopyState *s,
BlockCopyCallState *call_state,
int64_t offset, int64_t bytes)
{
BlockCopyTask *task;
int64_t max_chunk = MIN_NON_ZERO(s->copy_size, call_state->max_chunk);
if (!bdrv_dirty_bitmap_next_dirty_area(s->copy_bitmap,
offset, offset + bytes,
max_chunk, &offset, &bytes))
{
return NULL;
}
assert(QEMU_IS_ALIGNED(offset, s->cluster_size));
bytes = QEMU_ALIGN_UP(bytes, s->cluster_size);
/* region is dirty, so no existent tasks possible in it */
assert(!find_conflicting_task(s, offset, bytes));
bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, bytes);
s->in_flight_bytes += bytes;
task = g_new(BlockCopyTask, 1);
*task = (BlockCopyTask) {
.task.func = block_copy_task_entry,
.s = s,
.call_state = call_state,
.offset = offset,
.bytes = bytes,
};
qemu_co_queue_init(&task->wait_queue);
QLIST_INSERT_HEAD(&s->tasks, task, list);
return task;
}
/*
* block_copy_task_shrink
*
* Drop the tail of the task to be handled later. Set dirty bits back and
* wake up all tasks waiting for us (may be some of them are not intersecting
* with shrunk task)
*/
static void coroutine_fn block_copy_task_shrink(BlockCopyTask *task,
int64_t new_bytes)
{
if (new_bytes == task->bytes) {
return;
}
assert(new_bytes > 0 && new_bytes < task->bytes);
task->s->in_flight_bytes -= task->bytes - new_bytes;
bdrv_set_dirty_bitmap(task->s->copy_bitmap,
task->offset + new_bytes, task->bytes - new_bytes);
task->bytes = new_bytes;
qemu_co_queue_restart_all(&task->wait_queue);
}
static void coroutine_fn block_copy_task_end(BlockCopyTask *task, int ret)
{
task->s->in_flight_bytes -= task->bytes;
if (ret < 0) {
bdrv_set_dirty_bitmap(task->s->copy_bitmap, task->offset, task->bytes);
}
QLIST_REMOVE(task, list);
qemu_co_queue_restart_all(&task->wait_queue);
}
void block_copy_state_free(BlockCopyState *s)
{
if (!s) {
return;
}
ratelimit_destroy(&s->rate_limit);
bdrv_release_dirty_bitmap(s->copy_bitmap);
shres_destroy(s->mem);
g_free(s);
}
static uint32_t block_copy_max_transfer(BdrvChild *source, BdrvChild *target)
{
return MIN_NON_ZERO(INT_MAX,
MIN_NON_ZERO(source->bs->bl.max_transfer,
target->bs->bl.max_transfer));
}
BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
int64_t cluster_size, bool use_copy_range,
BdrvRequestFlags write_flags, Error **errp)
{
BlockCopyState *s;
BdrvDirtyBitmap *copy_bitmap;
copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
errp);
if (!copy_bitmap) {
return NULL;
}
bdrv_disable_dirty_bitmap(copy_bitmap);
s = g_new(BlockCopyState, 1);
*s = (BlockCopyState) {
.source = source,
.target = target,
.copy_bitmap = copy_bitmap,
.cluster_size = cluster_size,
.len = bdrv_dirty_bitmap_size(copy_bitmap),
.write_flags = write_flags,
.mem = shres_create(BLOCK_COPY_MAX_MEM),
};
if (block_copy_max_transfer(source, target) < cluster_size) {
/*
* copy_range does not respect max_transfer. We don't want to bother
* with requests smaller than block-copy cluster size, so fallback to
* buffered copying (read and write respect max_transfer on their
* behalf).
*/
s->use_copy_range = false;
s->copy_size = cluster_size;
} else if (write_flags & BDRV_REQ_WRITE_COMPRESSED) {
/* Compression supports only cluster-size writes and no copy-range. */
s->use_copy_range = false;
s->copy_size = cluster_size;
} else {
/*
* We enable copy-range, but keep small copy_size, until first
* successful copy_range (look at block_copy_do_copy).
*/
s->use_copy_range = use_copy_range;
s->copy_size = MAX(s->cluster_size, BLOCK_COPY_MAX_BUFFER);
}
ratelimit_init(&s->rate_limit);
QLIST_INIT(&s->tasks);
QLIST_INIT(&s->calls);
return s;
}
void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm)
{
s->progress = pm;
}
/*
* Takes ownership of @task
*
* If pool is NULL directly run the task, otherwise schedule it into the pool.
*
* Returns: task.func return code if pool is NULL
* otherwise -ECANCELED if pool status is bad
* otherwise 0 (successfully scheduled)
*/
static coroutine_fn int block_copy_task_run(AioTaskPool *pool,
BlockCopyTask *task)
{
if (!pool) {
int ret = task->task.func(&task->task);
g_free(task);
return ret;
}
aio_task_pool_wait_slot(pool);
if (aio_task_pool_status(pool) < 0) {
co_put_to_shres(task->s->mem, task->bytes);
block_copy_task_end(task, -ECANCELED);
g_free(task);
return -ECANCELED;
}
aio_task_pool_start_task(pool, &task->task);
return 0;
}
/*
* block_copy_do_copy
*
* Do copy of cluster-aligned chunk. Requested region is allowed to exceed
* s->len only to cover last cluster when s->len is not aligned to clusters.
*
* No sync here: nor bitmap neighter intersecting requests handling, only copy.
*
* Returns 0 on success.
*/
static int coroutine_fn block_copy_do_copy(BlockCopyState *s,
int64_t offset, int64_t bytes,
bool zeroes, bool *error_is_read)
{
int ret;
int64_t nbytes = MIN(offset + bytes, s->len) - offset;
void *bounce_buffer = NULL;
assert(offset >= 0 && bytes > 0 && INT64_MAX - offset >= bytes);
assert(QEMU_IS_ALIGNED(offset, s->cluster_size));
assert(QEMU_IS_ALIGNED(bytes, s->cluster_size));
assert(offset < s->len);
assert(offset + bytes <= s->len ||
offset + bytes == QEMU_ALIGN_UP(s->len, s->cluster_size));
assert(nbytes < INT_MAX);
if (zeroes) {
ret = bdrv_co_pwrite_zeroes(s->target, offset, nbytes, s->write_flags &
~BDRV_REQ_WRITE_COMPRESSED);
if (ret < 0) {
trace_block_copy_write_zeroes_fail(s, offset, ret);
*error_is_read = false;
}
return ret;
}
if (s->use_copy_range) {
ret = bdrv_co_copy_range(s->source, offset, s->target, offset, nbytes,
0, s->write_flags);
if (ret < 0) {
trace_block_copy_copy_range_fail(s, offset, ret);
s->use_copy_range = false;
s->copy_size = MAX(s->cluster_size, BLOCK_COPY_MAX_BUFFER);
/* Fallback to read+write with allocated buffer */
} else {
if (s->use_copy_range) {
/*
* Successful copy-range. Now increase copy_size. copy_range
* does not respect max_transfer (it's a TODO), so we factor
* that in here.
*
* Note: we double-check s->use_copy_range for the case when
* parallel block-copy request unsets it during previous
* bdrv_co_copy_range call.
*/
s->copy_size =
MIN(MAX(s->cluster_size, BLOCK_COPY_MAX_COPY_RANGE),
QEMU_ALIGN_DOWN(block_copy_max_transfer(s->source,
s->target),
s->cluster_size));
}
goto out;
}
}
/*
* In case of failed copy_range request above, we may proceed with buffered
* request larger than BLOCK_COPY_MAX_BUFFER. Still, further requests will
* be properly limited, so don't care too much. Moreover the most likely
* case (copy_range is unsupported for the configuration, so the very first
* copy_range request fails) is handled by setting large copy_size only
* after first successful copy_range.
*/
bounce_buffer = qemu_blockalign(s->source->bs, nbytes);
ret = bdrv_co_pread(s->source, offset, nbytes, bounce_buffer, 0);
if (ret < 0) {
trace_block_copy_read_fail(s, offset, ret);
*error_is_read = true;
goto out;
}
ret = bdrv_co_pwrite(s->target, offset, nbytes, bounce_buffer,
s->write_flags);
if (ret < 0) {
trace_block_copy_write_fail(s, offset, ret);
*error_is_read = false;
goto out;
}
out:
qemu_vfree(bounce_buffer);
return ret;
}
static coroutine_fn int block_copy_task_entry(AioTask *task)
{
BlockCopyTask *t = container_of(task, BlockCopyTask, task);
bool error_is_read = false;
int ret;
ret = block_copy_do_copy(t->s, t->offset, t->bytes, t->zeroes,
&error_is_read);
if (ret < 0 && !t->call_state->ret) {
t->call_state->ret = ret;
t->call_state->error_is_read = error_is_read;
} else {
progress_work_done(t->s->progress, t->bytes);
}
co_put_to_shres(t->s->mem, t->bytes);
block_copy_task_end(t, ret);
return ret;
}
static int block_copy_block_status(BlockCopyState *s, int64_t offset,
int64_t bytes, int64_t *pnum)
{
int64_t num;
BlockDriverState *base;
int ret;
if (s->skip_unallocated) {
base = bdrv_backing_chain_next(s->source->bs);
} else {
base = NULL;
}
ret = bdrv_block_status_above(s->source->bs, base, offset, bytes, &num,
NULL, NULL);
if (ret < 0 || num < s->cluster_size) {
/*
* On error or if failed to obtain large enough chunk just fallback to
* copy one cluster.
*/
num = s->cluster_size;
ret = BDRV_BLOCK_ALLOCATED | BDRV_BLOCK_DATA;
} else if (offset + num == s->len) {
num = QEMU_ALIGN_UP(num, s->cluster_size);
} else {
num = QEMU_ALIGN_DOWN(num, s->cluster_size);
}
*pnum = num;
return ret;
}
/*
* Check if the cluster starting at offset is allocated or not.
* return via pnum the number of contiguous clusters sharing this allocation.
*/
static int block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset,
int64_t *pnum)
{
BlockDriverState *bs = s->source->bs;
int64_t count, total_count = 0;
int64_t bytes = s->len - offset;
int ret;
assert(QEMU_IS_ALIGNED(offset, s->cluster_size));
while (true) {
ret = bdrv_is_allocated(bs, offset, bytes, &count);
if (ret < 0) {
return ret;
}
total_count += count;
if (ret || count == 0) {
/*
* ret: partial segment(s) are considered allocated.
* otherwise: unallocated tail is treated as an entire segment.
*/
*pnum = DIV_ROUND_UP(total_count, s->cluster_size);
return ret;
}
/* Unallocated segment(s) with uncertain following segment(s) */
if (total_count >= s->cluster_size) {
*pnum = total_count / s->cluster_size;
return 0;
}
offset += count;
bytes -= count;
}
}
/*
* Reset bits in copy_bitmap starting at offset if they represent unallocated
* data in the image. May reset subsequent contiguous bits.
* @return 0 when the cluster at @offset was unallocated,
* 1 otherwise, and -ret on error.
*/
int64_t block_copy_reset_unallocated(BlockCopyState *s,
int64_t offset, int64_t *count)
{
int ret;
int64_t clusters, bytes;
ret = block_copy_is_cluster_allocated(s, offset, &clusters);
if (ret < 0) {
return ret;
}
bytes = clusters * s->cluster_size;
if (!ret) {
bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, bytes);
progress_set_remaining(s->progress,
bdrv_get_dirty_count(s->copy_bitmap) +
s->in_flight_bytes);
}
*count = bytes;
return ret;
}
/*
* block_copy_dirty_clusters
*
* Copy dirty clusters in @offset/@bytes range.
* Returns 1 if dirty clusters found and successfully copied, 0 if no dirty
* clusters found and -errno on failure.
*/
static int coroutine_fn
block_copy_dirty_clusters(BlockCopyCallState *call_state)
{
BlockCopyState *s = call_state->s;
int64_t offset = call_state->offset;
int64_t bytes = call_state->bytes;
int ret = 0;
bool found_dirty = false;
int64_t end = offset + bytes;
AioTaskPool *aio = NULL;
/*
* block_copy() user is responsible for keeping source and target in same
* aio context
*/
assert(bdrv_get_aio_context(s->source->bs) ==
bdrv_get_aio_context(s->target->bs));
assert(QEMU_IS_ALIGNED(offset, s->cluster_size));
assert(QEMU_IS_ALIGNED(bytes, s->cluster_size));
while (bytes && aio_task_pool_status(aio) == 0 && !call_state->cancelled) {
BlockCopyTask *task;
int64_t status_bytes;
task = block_copy_task_create(s, call_state, offset, bytes);
if (!task) {
/* No more dirty bits in the bitmap */
trace_block_copy_skip_range(s, offset, bytes);
break;
}
if (task->offset > offset) {
trace_block_copy_skip_range(s, offset, task->offset - offset);
}
found_dirty = true;
ret = block_copy_block_status(s, task->offset, task->bytes,
&status_bytes);
assert(ret >= 0); /* never fail */
if (status_bytes < task->bytes) {
block_copy_task_shrink(task, status_bytes);
}
if (s->skip_unallocated && !(ret & BDRV_BLOCK_ALLOCATED)) {
block_copy_task_end(task, 0);
progress_set_remaining(s->progress,
bdrv_get_dirty_count(s->copy_bitmap) +
s->in_flight_bytes);
trace_block_copy_skip_range(s, task->offset, task->bytes);
offset = task_end(task);
bytes = end - offset;
g_free(task);
continue;
}
task->zeroes = ret & BDRV_BLOCK_ZERO;
if (s->speed) {
if (!call_state->ignore_ratelimit) {
uint64_t ns = ratelimit_calculate_delay(&s->rate_limit, 0);
if (ns > 0) {
block_copy_task_end(task, -EAGAIN);
g_free(task);
qemu_co_sleep_ns_wakeable(QEMU_CLOCK_REALTIME, ns,
&call_state->sleep_state);
continue;
}
}
ratelimit_calculate_delay(&s->rate_limit, task->bytes);
}
trace_block_copy_process(s, task->offset);
co_get_from_shres(s->mem, task->bytes);
offset = task_end(task);
bytes = end - offset;
if (!aio && bytes) {
aio = aio_task_pool_new(call_state->max_workers);
}
ret = block_copy_task_run(aio, task);
if (ret < 0) {
goto out;
}
}
out:
if (aio) {
aio_task_pool_wait_all(aio);
/*
* We are not really interested in -ECANCELED returned from
* block_copy_task_run. If it fails, it means some task already failed
* for real reason, let's return first failure.
* Still, assert that we don't rewrite failure by success.
*
* Note: ret may be positive here because of block-status result.
*/
assert(ret >= 0 || aio_task_pool_status(aio) < 0);
ret = aio_task_pool_status(aio);
aio_task_pool_free(aio);
}
return ret < 0 ? ret : found_dirty;
}
void block_copy_kick(BlockCopyCallState *call_state)
{
if (call_state->sleep_state) {
qemu_co_sleep_wake(call_state->sleep_state);
}
}
/*
* block_copy_common
*
* Copy requested region, accordingly to dirty bitmap.
* Collaborate with parallel block_copy requests: if they succeed it will help
* us. If they fail, we will retry not-copied regions. So, if we return error,
* it means that some I/O operation failed in context of _this_ block_copy call,
* not some parallel operation.
*/
static int coroutine_fn block_copy_common(BlockCopyCallState *call_state)
{
int ret;
QLIST_INSERT_HEAD(&call_state->s->calls, call_state, list);
do {
ret = block_copy_dirty_clusters(call_state);
if (ret == 0 && !call_state->cancelled) {
ret = block_copy_wait_one(call_state->s, call_state->offset,
call_state->bytes);
}
/*
* We retry in two cases:
* 1. Some progress done
* Something was copied, which means that there were yield points
* and some new dirty bits may have appeared (due to failed parallel
* block-copy requests).
* 2. We have waited for some intersecting block-copy request
* It may have failed and produced new dirty bits.
*/
} while (ret > 0 && !call_state->cancelled);
call_state->finished = true;
if (call_state->cb) {
call_state->cb(call_state->cb_opaque);
}
QLIST_REMOVE(call_state, list);
return ret;
}
int coroutine_fn block_copy(BlockCopyState *s, int64_t start, int64_t bytes,
bool ignore_ratelimit)
{
BlockCopyCallState call_state = {
.s = s,
.offset = start,
.bytes = bytes,
.ignore_ratelimit = ignore_ratelimit,
.max_workers = BLOCK_COPY_MAX_WORKERS,
};
return block_copy_common(&call_state);
}
static void coroutine_fn block_copy_async_co_entry(void *opaque)
{
block_copy_common(opaque);
}
BlockCopyCallState *block_copy_async(BlockCopyState *s,
int64_t offset, int64_t bytes,
int max_workers, int64_t max_chunk,
BlockCopyAsyncCallbackFunc cb,
void *cb_opaque)
{
BlockCopyCallState *call_state = g_new(BlockCopyCallState, 1);
*call_state = (BlockCopyCallState) {
.s = s,
.offset = offset,
.bytes = bytes,
.max_workers = max_workers,
.max_chunk = max_chunk,
.cb = cb,
.cb_opaque = cb_opaque,
.co = qemu_coroutine_create(block_copy_async_co_entry, call_state),
};
qemu_coroutine_enter(call_state->co);
return call_state;
}
void block_copy_call_free(BlockCopyCallState *call_state)
{
if (!call_state) {
return;
}
assert(call_state->finished);
g_free(call_state);
}
bool block_copy_call_finished(BlockCopyCallState *call_state)
{
return call_state->finished;
}
bool block_copy_call_succeeded(BlockCopyCallState *call_state)
{
return call_state->finished && !call_state->cancelled &&
call_state->ret == 0;
}
bool block_copy_call_failed(BlockCopyCallState *call_state)
{
return call_state->finished && !call_state->cancelled &&
call_state->ret < 0;
}
bool block_copy_call_cancelled(BlockCopyCallState *call_state)
{
return call_state->cancelled;
}
int block_copy_call_status(BlockCopyCallState *call_state, bool *error_is_read)
{
assert(call_state->finished);
if (error_is_read) {
*error_is_read = call_state->error_is_read;
}
return call_state->ret;
}
void block_copy_call_cancel(BlockCopyCallState *call_state)
{
call_state->cancelled = true;
block_copy_kick(call_state);
}
BdrvDirtyBitmap *block_copy_dirty_bitmap(BlockCopyState *s)
{
return s->copy_bitmap;
}
void block_copy_set_skip_unallocated(BlockCopyState *s, bool skip)
{
s->skip_unallocated = skip;
}
void block_copy_set_speed(BlockCopyState *s, uint64_t speed)
{
s->speed = speed;
if (speed > 0) {
ratelimit_set_speed(&s->rate_limit, speed, BLOCK_COPY_SLICE_TIME);
}
/*
* Note: it's good to kick all call states from here, but it should be done
* only from a coroutine, to not crash if s->calls list changed while
* entering one call. So for now, the only user of this function kicks its
* only one call_state by hand.
*/
}
Reference in New Issue View Git Blame Copy Permalink