diff options
author | Daniel P. Berrange <berrange@redhat.com> | 2015-09-01 14:48:02 +0100 |
---|---|---|
committer | Daniel P. Berrange <berrange@redhat.com> | 2015-10-20 14:59:04 +0100 |
commit | 10817bf09d5f8cb22711fb0ee8d8da49f6f05f89 (patch) | |
tree | 735f6b70cedecd57843b9108cb68e2359e147e0c /qemu-coroutine.c | |
parent | 57cb38b3833c5215131b983f181b26d6ba9b8d35 (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.c | 146 |
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); -} |