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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 /coroutine-gthread.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 'coroutine-gthread.c')
-rw-r--r--coroutine-gthread.c198
1 files changed, 0 insertions, 198 deletions
diff --git a/coroutine-gthread.c b/coroutine-gthread.c
deleted file mode 100644
index 6bd6d6b22f..0000000000
--- a/coroutine-gthread.c
+++ /dev/null
@@ -1,198 +0,0 @@
-/*
- * GThread coroutine initialization code
- *
- * Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>
- * Copyright (C) 2011 Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.0 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <glib.h>
-#include "qemu-common.h"
-#include "block/coroutine_int.h"
-
-typedef struct {
- Coroutine base;
- GThread *thread;
- bool runnable;
- bool free_on_thread_exit;
- CoroutineAction action;
-} CoroutineGThread;
-
-static CompatGMutex coroutine_lock;
-static CompatGCond coroutine_cond;
-
-/* GLib 2.31 and beyond deprecated various parts of the thread API,
- * but the new interfaces are not available in older GLib versions
- * so we have to cope with both.
- */
-#if GLIB_CHECK_VERSION(2, 31, 0)
-/* Awkwardly, the GPrivate API doesn't provide a way to update the
- * GDestroyNotify handler for the coroutine key dynamically. So instead
- * we track whether or not the CoroutineGThread should be freed on
- * thread exit / coroutine key update using the free_on_thread_exit
- * field.
- */
-static void coroutine_destroy_notify(gpointer data)
-{
- CoroutineGThread *co = data;
- if (co && co->free_on_thread_exit) {
- g_free(co);
- }
-}
-
-static GPrivate coroutine_key = G_PRIVATE_INIT(coroutine_destroy_notify);
-
-static inline CoroutineGThread *get_coroutine_key(void)
-{
- return g_private_get(&coroutine_key);
-}
-
-static inline void set_coroutine_key(CoroutineGThread *co,
- bool free_on_thread_exit)
-{
- /* Unlike g_static_private_set() this does not call the GDestroyNotify
- * if the previous value of the key was NULL. Fortunately we only need
- * the GDestroyNotify in the non-NULL key case.
- */
- co->free_on_thread_exit = free_on_thread_exit;
- g_private_replace(&coroutine_key, co);
-}
-
-static inline GThread *create_thread(GThreadFunc func, gpointer data)
-{
- return g_thread_new("coroutine", func, data);
-}
-
-#else
-
-/* Handle older GLib versions */
-
-static GStaticPrivate coroutine_key = G_STATIC_PRIVATE_INIT;
-
-static inline CoroutineGThread *get_coroutine_key(void)
-{
- return g_static_private_get(&coroutine_key);
-}
-
-static inline void set_coroutine_key(CoroutineGThread *co,
- bool free_on_thread_exit)
-{
- g_static_private_set(&coroutine_key, co,
- free_on_thread_exit ? (GDestroyNotify)g_free : NULL);
-}
-
-static inline GThread *create_thread(GThreadFunc func, gpointer data)
-{
- return g_thread_create_full(func, data, 0, TRUE, TRUE,
- G_THREAD_PRIORITY_NORMAL, NULL);
-}
-
-#endif
-
-
-static void __attribute__((constructor)) coroutine_init(void)
-{
-#if !GLIB_CHECK_VERSION(2, 31, 0)
- if (!g_thread_supported()) {
- g_thread_init(NULL);
- }
-#endif
-}
-
-static void coroutine_wait_runnable_locked(CoroutineGThread *co)
-{
- while (!co->runnable) {
- g_cond_wait(&coroutine_cond, &coroutine_lock);
- }
-}
-
-static void coroutine_wait_runnable(CoroutineGThread *co)
-{
- g_mutex_lock(&coroutine_lock);
- coroutine_wait_runnable_locked(co);
- g_mutex_unlock(&coroutine_lock);
-}
-
-static gpointer coroutine_thread(gpointer opaque)
-{
- CoroutineGThread *co = opaque;
-
- set_coroutine_key(co, false);
- coroutine_wait_runnable(co);
- co->base.entry(co->base.entry_arg);
- qemu_coroutine_switch(&co->base, co->base.caller, COROUTINE_TERMINATE);
- return NULL;
-}
-
-Coroutine *qemu_coroutine_new(void)
-{
- CoroutineGThread *co;
-
- co = g_malloc0(sizeof(*co));
- co->thread = create_thread(coroutine_thread, co);
- if (!co->thread) {
- g_free(co);
- return NULL;
- }
- return &co->base;
-}
-
-void qemu_coroutine_delete(Coroutine *co_)
-{
- CoroutineGThread *co = DO_UPCAST(CoroutineGThread, base, co_);
-
- g_thread_join(co->thread);
- g_free(co);
-}
-
-CoroutineAction qemu_coroutine_switch(Coroutine *from_,
- Coroutine *to_,
- CoroutineAction action)
-{
- CoroutineGThread *from = DO_UPCAST(CoroutineGThread, base, from_);
- CoroutineGThread *to = DO_UPCAST(CoroutineGThread, base, to_);
-
- g_mutex_lock(&coroutine_lock);
- from->runnable = false;
- from->action = action;
- to->runnable = true;
- to->action = action;
- g_cond_broadcast(&coroutine_cond);
-
- if (action != COROUTINE_TERMINATE) {
- coroutine_wait_runnable_locked(from);
- }
- g_mutex_unlock(&coroutine_lock);
- return from->action;
-}
-
-Coroutine *qemu_coroutine_self(void)
-{
- CoroutineGThread *co = get_coroutine_key();
- if (!co) {
- co = g_malloc0(sizeof(*co));
- co->runnable = true;
- set_coroutine_key(co, true);
- }
-
- return &co->base;
-}
-
-bool qemu_in_coroutine(void)
-{
- CoroutineGThread *co = get_coroutine_key();
-
- return co && co->base.caller;
-}