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Diffstat (limited to 'util/qemu-co-shared-resource.c')
-rw-r--r--util/qemu-co-shared-resource.c24
1 files changed, 19 insertions, 5 deletions
diff --git a/util/qemu-co-shared-resource.c b/util/qemu-co-shared-resource.c
index 1c83cd9d29..a66cc07e75 100644
--- a/util/qemu-co-shared-resource.c
+++ b/util/qemu-co-shared-resource.c
@@ -28,10 +28,13 @@
#include "qemu/co-shared-resource.h"
struct SharedResource {
- uint64_t total;
- uint64_t available;
+ uint64_t total; /* Set in shres_create() and not changed anymore */
+ /* State fields protected by lock */
+ uint64_t available;
CoQueue queue;
+
+ QemuMutex lock;
};
SharedResource *shres_create(uint64_t total)
@@ -40,6 +43,7 @@ SharedResource *shres_create(uint64_t total)
s->total = s->available = total;
qemu_co_queue_init(&s->queue);
+ qemu_mutex_init(&s->lock);
return s;
}
@@ -47,10 +51,12 @@ SharedResource *shres_create(uint64_t total)
void shres_destroy(SharedResource *s)
{
assert(s->available == s->total);
+ qemu_mutex_destroy(&s->lock);
g_free(s);
}
-bool co_try_get_from_shres(SharedResource *s, uint64_t n)
+/* Called with lock held. */
+static bool co_try_get_from_shres_locked(SharedResource *s, uint64_t n)
{
if (s->available >= n) {
s->available -= n;
@@ -60,16 +66,24 @@ bool co_try_get_from_shres(SharedResource *s, uint64_t n)
return false;
}
+bool co_try_get_from_shres(SharedResource *s, uint64_t n)
+{
+ QEMU_LOCK_GUARD(&s->lock);
+ return co_try_get_from_shres_locked(s, n);
+}
+
void coroutine_fn co_get_from_shres(SharedResource *s, uint64_t n)
{
assert(n <= s->total);
- while (!co_try_get_from_shres(s, n)) {
- qemu_co_queue_wait(&s->queue, NULL);
+ QEMU_LOCK_GUARD(&s->lock);
+ while (!co_try_get_from_shres_locked(s, n)) {
+ qemu_co_queue_wait(&s->queue, &s->lock);
}
}
void coroutine_fn co_put_to_shres(SharedResource *s, uint64_t n)
{
+ QEMU_LOCK_GUARD(&s->lock);
assert(s->total - s->available >= n);
s->available += n;
qemu_co_queue_restart_all(&s->queue);