#include "block/blockjob_int.h"
#include "block/block_int.h"
#include "sysemu/block-backend.h"
+#include "qapi/error.h"
+#include "qapi/qapi-events-block-core.h"
#include "qapi/qmp/qerror.h"
-#include "qapi/qmp/qjson.h"
#include "qemu/coroutine.h"
#include "qemu/id.h"
-#include "qmp-commands.h"
#include "qemu/timer.h"
-#include "qapi-event.h"
+
+/* Right now, this mutex is only needed to synchronize accesses to job->busy
+ * and job->sleep_timer, such as concurrent calls to block_job_do_yield and
+ * block_job_enter. */
+static QemuMutex block_job_mutex;
+
+static void block_job_lock(void)
+{
+ qemu_mutex_lock(&block_job_mutex);
+}
+
+static void block_job_unlock(void)
+{
+ qemu_mutex_unlock(&block_job_mutex);
+}
+
+static void __attribute__((__constructor__)) block_job_init(void)
+{
+ qemu_mutex_init(&block_job_mutex);
+}
static void block_job_event_cancelled(BlockJob *job);
static void block_job_event_completed(BlockJob *job, const char *msg);
+static void block_job_enter_cond(BlockJob *job, bool(*fn)(BlockJob *job));
/* Transactional group of block jobs */
struct BlockJobTxn {
blk_unref(job->blk);
error_free(job->blocker);
g_free(job->id);
+ assert(!timer_pending(&job->sleep_timer));
g_free(job);
}
}
job->id);
}
-static const BdrvChildRole child_job = {
- .get_parent_desc = child_job_get_parent_desc,
- .stay_at_node = true,
-};
-
-static void block_job_drained_begin(void *opaque)
+static void child_job_drained_begin(BdrvChild *c)
{
- BlockJob *job = opaque;
+ BlockJob *job = c->opaque;
block_job_pause(job);
}
-static void block_job_drained_end(void *opaque)
+static void child_job_drained_end(BdrvChild *c)
{
- BlockJob *job = opaque;
+ BlockJob *job = c->opaque;
block_job_resume(job);
}
-static const BlockDevOps block_job_dev_ops = {
- .drained_begin = block_job_drained_begin,
- .drained_end = block_job_drained_end,
+static const BdrvChildRole child_job = {
+ .get_parent_desc = child_job_get_parent_desc,
+ .drained_begin = child_job_drained_begin,
+ .drained_end = child_job_drained_end,
+ .stay_at_node = true,
};
void block_job_remove_all_bdrv(BlockJob *job)
job->driver->start(job);
}
+static void block_job_sleep_timer_cb(void *opaque)
+{
+ BlockJob *job = opaque;
+
+ block_job_enter(job);
+}
+
void block_job_start(BlockJob *job)
{
assert(job && !block_job_started(job) && job->paused &&
}
}
+/* Assumes the block_job_mutex is held */
+static bool block_job_timer_pending(BlockJob *job)
+{
+ return timer_pending(&job->sleep_timer);
+}
+
void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
{
Error *local_err = NULL;
+ int64_t old_speed = job->speed;
if (!job->driver->set_speed) {
error_setg(errp, QERR_UNSUPPORTED);
}
job->speed = speed;
+ if (speed <= old_speed) {
+ return;
+ }
+
+ /* kick only if a timer is pending */
+ block_job_enter_cond(job, block_job_timer_pending);
}
void block_job_complete(BlockJob *job, Error **errp)
info->type = g_strdup(BlockJobType_str(job->driver->job_type));
info->device = g_strdup(job->id);
info->len = job->len;
- info->busy = job->busy;
+ info->busy = atomic_read(&job->busy);
info->paused = job->pause_count > 0;
info->offset = job->offset;
info->speed = job->speed;
job->paused = true;
job->pause_count = 1;
job->refcnt = 1;
+ aio_timer_init(qemu_get_aio_context(), &job->sleep_timer,
+ QEMU_CLOCK_REALTIME, SCALE_NS,
+ block_job_sleep_timer_cb, job);
error_setg(&job->blocker, "block device is in use by block job: %s",
BlockJobType_str(driver->job_type));
block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
bs->job = job;
- blk_set_dev_ops(blk, &block_job_dev_ops, job);
bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
QLIST_INSERT_HEAD(&block_jobs, job, job_list);
AioContext *aio_context = blk_get_aio_context(job->blk);
aio_context_acquire(aio_context);
+ block_job_ref(job);
block_job_pause(job);
aio_context_release(aio_context);
}
return job->pause_count > 0;
}
+/* Yield, and schedule a timer to reenter the coroutine after @ns nanoseconds.
+ * Reentering the job coroutine with block_job_enter() before the timer has
+ * expired is allowed and cancels the timer.
+ *
+ * If @ns is (uint64_t) -1, no timer is scheduled and block_job_enter() must be
+ * called explicitly. */
+static void block_job_do_yield(BlockJob *job, uint64_t ns)
+{
+ block_job_lock();
+ if (ns != -1) {
+ timer_mod(&job->sleep_timer, ns);
+ }
+ job->busy = false;
+ block_job_unlock();
+ qemu_coroutine_yield();
+
+ /* Set by block_job_enter before re-entering the coroutine. */
+ assert(job->busy);
+}
+
void coroutine_fn block_job_pause_point(BlockJob *job)
{
assert(job && block_job_started(job));
if (block_job_should_pause(job) && !block_job_is_cancelled(job)) {
job->paused = true;
- job->busy = false;
- qemu_coroutine_yield(); /* wait for block_job_resume() */
- job->busy = true;
+ block_job_do_yield(job, -1);
job->paused = false;
}
void block_job_resume_all(void)
{
- BlockJob *job = NULL;
- while ((job = block_job_next(job))) {
+ BlockJob *job, *next;
+
+ QLIST_FOREACH_SAFE(job, &block_jobs, job_list, next) {
AioContext *aio_context = blk_get_aio_context(job->blk);
aio_context_acquire(aio_context);
block_job_resume(job);
+ block_job_unref(job);
aio_context_release(aio_context);
}
}
-void block_job_enter(BlockJob *job)
+/*
+ * Conditionally enter a block_job pending a call to fn() while
+ * under the block_job_lock critical section.
+ */
+static void block_job_enter_cond(BlockJob *job, bool(*fn)(BlockJob *job))
{
if (!block_job_started(job)) {
return;
return;
}
- if (!job->busy) {
- bdrv_coroutine_enter(blk_bs(job->blk), job->co);
+ block_job_lock();
+ if (job->busy) {
+ block_job_unlock();
+ return;
+ }
+
+ if (fn && !fn(job)) {
+ block_job_unlock();
+ return;
}
+
+ assert(!job->deferred_to_main_loop);
+ timer_del(&job->sleep_timer);
+ job->busy = true;
+ block_job_unlock();
+ aio_co_wake(job->co);
+}
+
+void block_job_enter(BlockJob *job)
+{
+ block_job_enter_cond(job, NULL);
}
bool block_job_is_cancelled(BlockJob *job)
return job->cancelled;
}
-void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
+void block_job_sleep_ns(BlockJob *job, int64_t ns)
{
assert(job->busy);
return;
}
- /* We need to leave job->busy set here, because when we have
- * put a coroutine to 'sleep', we have scheduled it to run in
- * the future. We cannot enter that same coroutine again before
- * it wakes and runs, otherwise we risk double-entry or entry after
- * completion. */
if (!block_job_should_pause(job)) {
- co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns);
+ block_job_do_yield(job, qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + ns);
}
block_job_pause_point(job);
return;
}
- job->busy = false;
if (!block_job_should_pause(job)) {
- qemu_coroutine_yield();
+ block_job_do_yield(job, -1);
}
- job->busy = true;
block_job_pause_point(job);
}
projects / qemu.git / blobdiff