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authorKevin Wolf <kwolf@redhat.com>2009-10-22 17:54:37 +0200
committerAnthony Liguori <aliguori@us.ibm.com>2009-10-27 12:28:59 -0500
commit4f999d05f55586ba73494c5ada6d9c5eb9eb800c (patch)
tree32e3028b10be26d3a354a32f2d8586bf37ce0907 /async.c
parent8febfa26846e75d38848255028dfe2d06e5ba941 (diff)
downloadqemu-arm-4f999d05f55586ba73494c5ada6d9c5eb9eb800c.tar.gz
Split out bottom halves
Instead of putting more and more stuff into vl.c, let's have the generic functions that deal with asynchronous callbacks in their own file. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'async.c')
-rw-r--r--async.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/async.c b/async.c
new file mode 100644
index 0000000000..60c1cb37da
--- /dev/null
+++ b/async.c
@@ -0,0 +1,130 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu-common.h"
+
+/***********************************************************/
+/* bottom halves (can be seen as timers which expire ASAP) */
+
+struct QEMUBH {
+ QEMUBHFunc *cb;
+ void *opaque;
+ int scheduled;
+ int idle;
+ int deleted;
+ QEMUBH *next;
+};
+
+static QEMUBH *first_bh = NULL;
+
+QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque)
+{
+ QEMUBH *bh;
+ bh = qemu_mallocz(sizeof(QEMUBH));
+ bh->cb = cb;
+ bh->opaque = opaque;
+ bh->next = first_bh;
+ first_bh = bh;
+ return bh;
+}
+
+int qemu_bh_poll(void)
+{
+ QEMUBH *bh, **bhp;
+ int ret;
+
+ ret = 0;
+ for (bh = first_bh; bh; bh = bh->next) {
+ if (!bh->deleted && bh->scheduled) {
+ bh->scheduled = 0;
+ if (!bh->idle)
+ ret = 1;
+ bh->idle = 0;
+ bh->cb(bh->opaque);
+ }
+ }
+
+ /* remove deleted bhs */
+ bhp = &first_bh;
+ while (*bhp) {
+ bh = *bhp;
+ if (bh->deleted) {
+ *bhp = bh->next;
+ qemu_free(bh);
+ } else
+ bhp = &bh->next;
+ }
+
+ return ret;
+}
+
+void qemu_bh_schedule_idle(QEMUBH *bh)
+{
+ if (bh->scheduled)
+ return;
+ bh->scheduled = 1;
+ bh->idle = 1;
+}
+
+void qemu_bh_schedule(QEMUBH *bh)
+{
+ if (bh->scheduled)
+ return;
+ bh->scheduled = 1;
+ bh->idle = 0;
+ /* stop the currently executing CPU to execute the BH ASAP */
+ qemu_notify_event();
+}
+
+void qemu_bh_cancel(QEMUBH *bh)
+{
+ bh->scheduled = 0;
+}
+
+void qemu_bh_delete(QEMUBH *bh)
+{
+ bh->scheduled = 0;
+ bh->deleted = 1;
+}
+
+void qemu_bh_update_timeout(int *timeout)
+{
+ QEMUBH *bh;
+
+ for (bh = first_bh; bh; bh = bh->next) {
+ if (!bh->deleted && bh->scheduled) {
+ if (bh->idle) {
+ /* idle bottom halves will be polled at least
+ * every 10ms */
+ *timeout = MIN(10, *timeout);
+ } else {
+ /* non-idle bottom halves will be executed
+ * immediately */
+ *timeout = 0;
+ break;
+ }
+ }
+ }
+}
+