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authorDaniel P. Berrange <berrange@redhat.com>2015-09-01 14:48:02 +0100
committerDaniel P. Berrange <berrange@redhat.com>2015-10-20 14:59:04 +0100
commit10817bf09d5f8cb22711fb0ee8d8da49f6f05f89 (patch)
tree735f6b70cedecd57843b9108cb68e2359e147e0c /qemu-coroutine.c
parent57cb38b3833c5215131b983f181b26d6ba9b8d35 (diff)
coroutine: move into libqemuutil.a library
The coroutine files are currently referenced by the block-obj-y variable. The coroutine functionality though is already used by more than just the block code. eg migration code uses coroutine yield. In the future the I/O channel code will also use the coroutine yield functionality. Since the coroutine code is nicely self-contained it can be easily built as part of the libqemuutil.a library, making it widely available. The headers are also moved into include/qemu, instead of the include/block directory, since they are now part of the util codebase, and the impl was never in the block/ directory either. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Diffstat (limited to 'qemu-coroutine.c')
-rw-r--r--qemu-coroutine.c146
1 files changed, 0 insertions, 146 deletions
diff --git a/qemu-coroutine.c b/qemu-coroutine.c
deleted file mode 100644
index c17a92b107..0000000000
--- a/qemu-coroutine.c
+++ /dev/null
@@ -1,146 +0,0 @@
-/*
- * QEMU coroutines
- *
- * Copyright IBM, Corp. 2011
- *
- * Authors:
- * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
- * Kevin Wolf <kwolf@redhat.com>
- *
- * This work is licensed under the terms of the GNU LGPL, version 2 or later.
- * See the COPYING.LIB file in the top-level directory.
- *
- */
-
-#include "trace.h"
-#include "qemu-common.h"
-#include "qemu/thread.h"
-#include "qemu/atomic.h"
-#include "block/coroutine.h"
-#include "block/coroutine_int.h"
-
-enum {
- POOL_BATCH_SIZE = 64,
-};
-
-/** Free list to speed up creation */
-static QSLIST_HEAD(, Coroutine) release_pool = QSLIST_HEAD_INITIALIZER(pool);
-static unsigned int release_pool_size;
-static __thread QSLIST_HEAD(, Coroutine) alloc_pool = QSLIST_HEAD_INITIALIZER(pool);
-static __thread unsigned int alloc_pool_size;
-static __thread Notifier coroutine_pool_cleanup_notifier;
-
-static void coroutine_pool_cleanup(Notifier *n, void *value)
-{
- Coroutine *co;
- Coroutine *tmp;
-
- QSLIST_FOREACH_SAFE(co, &alloc_pool, pool_next, tmp) {
- QSLIST_REMOVE_HEAD(&alloc_pool, pool_next);
- qemu_coroutine_delete(co);
- }
-}
-
-Coroutine *qemu_coroutine_create(CoroutineEntry *entry)
-{
- Coroutine *co = NULL;
-
- if (CONFIG_COROUTINE_POOL) {
- co = QSLIST_FIRST(&alloc_pool);
- if (!co) {
- if (release_pool_size > POOL_BATCH_SIZE) {
- /* Slow path; a good place to register the destructor, too. */
- if (!coroutine_pool_cleanup_notifier.notify) {
- coroutine_pool_cleanup_notifier.notify = coroutine_pool_cleanup;
- qemu_thread_atexit_add(&coroutine_pool_cleanup_notifier);
- }
-
- /* This is not exact; there could be a little skew between
- * release_pool_size and the actual size of release_pool. But
- * it is just a heuristic, it does not need to be perfect.
- */
- alloc_pool_size = atomic_xchg(&release_pool_size, 0);
- QSLIST_MOVE_ATOMIC(&alloc_pool, &release_pool);
- co = QSLIST_FIRST(&alloc_pool);
- }
- }
- if (co) {
- QSLIST_REMOVE_HEAD(&alloc_pool, pool_next);
- alloc_pool_size--;
- }
- }
-
- if (!co) {
- co = qemu_coroutine_new();
- }
-
- co->entry = entry;
- QTAILQ_INIT(&co->co_queue_wakeup);
- return co;
-}
-
-static void coroutine_delete(Coroutine *co)
-{
- co->caller = NULL;
-
- if (CONFIG_COROUTINE_POOL) {
- if (release_pool_size < POOL_BATCH_SIZE * 2) {
- QSLIST_INSERT_HEAD_ATOMIC(&release_pool, co, pool_next);
- atomic_inc(&release_pool_size);
- return;
- }
- if (alloc_pool_size < POOL_BATCH_SIZE) {
- QSLIST_INSERT_HEAD(&alloc_pool, co, pool_next);
- alloc_pool_size++;
- return;
- }
- }
-
- qemu_coroutine_delete(co);
-}
-
-void qemu_coroutine_enter(Coroutine *co, void *opaque)
-{
- Coroutine *self = qemu_coroutine_self();
- CoroutineAction ret;
-
- trace_qemu_coroutine_enter(self, co, opaque);
-
- if (co->caller) {
- fprintf(stderr, "Co-routine re-entered recursively\n");
- abort();
- }
-
- co->caller = self;
- co->entry_arg = opaque;
- ret = qemu_coroutine_switch(self, co, COROUTINE_ENTER);
-
- qemu_co_queue_run_restart(co);
-
- switch (ret) {
- case COROUTINE_YIELD:
- return;
- case COROUTINE_TERMINATE:
- trace_qemu_coroutine_terminate(co);
- coroutine_delete(co);
- return;
- default:
- abort();
- }
-}
-
-void coroutine_fn qemu_coroutine_yield(void)
-{
- Coroutine *self = qemu_coroutine_self();
- Coroutine *to = self->caller;
-
- trace_qemu_coroutine_yield(self, to);
-
- if (!to) {
- fprintf(stderr, "Co-routine is yielding to no one\n");
- abort();
- }
-
- self->caller = NULL;
- qemu_coroutine_switch(self, to, COROUTINE_YIELD);
-}