From 2da61b671eb89fcaa306738f44eed472977d6587 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 3 Mar 2014 11:30:03 +0100 Subject: rfifolock: add recursive FIFO lock QemuMutex does not guarantee fairness and cannot be acquired recursively: Fairness means each locker gets a turn and the scheduler cannot cause starvation. Recursive locking is useful for composition, it allows a sequence of locking operations to be invoked atomically by acquiring the lock around them. This patch adds RFifoLock, a recursive lock that guarantees FIFO order. Its first user is added in the next patch. RFifoLock has one additional feature: it can be initialized with an optional contention callback. The callback is invoked whenever a thread must wait for the lock. For example, it can be used to poke the current owner so that they release the lock soon. Signed-off-by: Stefan Hajnoczi --- util/Makefile.objs | 1 + 1 file changed, 1 insertion(+) (limited to 'util/Makefile.objs') diff --git a/util/Makefile.objs b/util/Makefile.objs index 937376b082..df83b629a0 100644 --- a/util/Makefile.objs +++ b/util/Makefile.objs @@ -14,3 +14,4 @@ util-obj-y += crc32c.o util-obj-y += throttle.o util-obj-y += getauxval.o util-obj-y += readline.o +util-obj-y += rfifolock.o -- cgit v1.2.3-55-g7522