From 988fcafc730242711ba92f9e62557e37f2b22cc0 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 14 Aug 2018 09:48:29 +0200 Subject: [PATCH] seqlock: add QemuLockable support A shortcut when the seqlock write is protected by a spinlock or any mutex other than the BQL. Signed-off-by: Paolo Bonzini --- include/qemu/seqlock.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/include/qemu/seqlock.h b/include/qemu/seqlock.h index c367516708..fd408b7ec5 100644 --- a/include/qemu/seqlock.h +++ b/include/qemu/seqlock.h @@ -16,6 +16,7 @@ #include "qemu/atomic.h" #include "qemu/thread.h" +#include "qemu/lockable.h" typedef struct QemuSeqLock QemuSeqLock; @@ -45,6 +46,25 @@ static inline void seqlock_write_end(QemuSeqLock *sl) atomic_set(&sl->sequence, sl->sequence + 1); } +/* Lock out other writers and update the count. */ +static inline void seqlock_write_lock_impl(QemuSeqLock *sl, QemuLockable *lock) +{ + qemu_lockable_lock(lock); + seqlock_write_begin(sl); +} +#define seqlock_write_lock(sl, lock) \ + seqlock_write_lock_impl(sl, QEMU_MAKE_LOCKABLE(lock)) + +/* Lock out other writers and update the count. */ +static inline void seqlock_write_unlock_impl(QemuSeqLock *sl, QemuLockable *lock) +{ + qemu_lockable_unlock(lock); + seqlock_write_begin(sl); +} +#define seqlock_write_unlock(sl, lock) \ + seqlock_write_unlock_impl(sl, QEMU_MAKE_LOCKABLE(lock)) + + static inline unsigned seqlock_read_begin(const QemuSeqLock *sl) { /* Always fail if a write is in progress. */ -- 2.11.4.GIT