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Diffstat (limited to 'include/qemu/rfifolock.h')
-rw-r--r-- | include/qemu/rfifolock.h | 54 |
1 files changed, 0 insertions, 54 deletions
diff --git a/include/qemu/rfifolock.h b/include/qemu/rfifolock.h deleted file mode 100644 index b23ab538a6..0000000000 --- a/include/qemu/rfifolock.h +++ /dev/null @@ -1,54 +0,0 @@ -/* - * Recursive FIFO lock - * - * Copyright Red Hat, Inc. 2013 - * - * Authors: - * Stefan Hajnoczi <stefanha@redhat.com> - * - * This work is licensed under the terms of the GNU GPL, version 2 or later. - * See the COPYING file in the top-level directory. - * - */ - -#ifndef QEMU_RFIFOLOCK_H -#define QEMU_RFIFOLOCK_H - -#include "qemu/thread.h" - -/* Recursive FIFO lock - * - * This lock provides more features than a plain mutex: - * - * 1. Fairness - enforces FIFO order. - * 2. Nesting - can be taken recursively. - * 3. Contention callback - optional, called when thread must wait. - * - * The recursive FIFO lock is heavyweight so prefer other synchronization - * primitives if you do not need its features. - */ -typedef struct { - QemuMutex lock; /* protects all fields */ - - /* FIFO order */ - unsigned int head; /* active ticket number */ - unsigned int tail; /* waiting ticket number */ - QemuCond cond; /* used to wait for our ticket number */ - - /* Nesting */ - QemuThread owner_thread; /* thread that currently has ownership */ - unsigned int nesting; /* amount of nesting levels */ - - /* Contention callback */ - void (*cb)(void *); /* called when thread must wait, with ->lock - * held so it may not recursively lock/unlock - */ - void *cb_opaque; -} RFifoLock; - -void rfifolock_init(RFifoLock *r, void (*cb)(void *), void *opaque); -void rfifolock_destroy(RFifoLock *r); -void rfifolock_lock(RFifoLock *r); -void rfifolock_unlock(RFifoLock *r); - -#endif /* QEMU_RFIFOLOCK_H */ |