diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
---|---|---|
committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/linux/spinlock_up.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/linux/spinlock_up.h')
-rw-r--r-- | kernel/include/linux/spinlock_up.h | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/kernel/include/linux/spinlock_up.h b/kernel/include/linux/spinlock_up.h new file mode 100644 index 000000000..8b3ac0d71 --- /dev/null +++ b/kernel/include/linux/spinlock_up.h @@ -0,0 +1,85 @@ +#ifndef __LINUX_SPINLOCK_UP_H +#define __LINUX_SPINLOCK_UP_H + +#ifndef __LINUX_SPINLOCK_H +# error "please don't include this file directly" +#endif + +#include <asm/processor.h> /* for cpu_relax() */ + +/* + * include/linux/spinlock_up.h - UP-debug version of spinlocks. + * + * portions Copyright 2005, Red Hat, Inc., Ingo Molnar + * Released under the General Public License (GPL). + * + * In the debug case, 1 means unlocked, 0 means locked. (the values + * are inverted, to catch initialization bugs) + * + * No atomicity anywhere, we are on UP. However, we still need + * the compiler barriers, because we do not want the compiler to + * move potentially faulting instructions (notably user accesses) + * into the locked sequence, resulting in non-atomic execution. + */ + +#ifdef CONFIG_DEBUG_SPINLOCK +#define arch_spin_is_locked(x) ((x)->slock == 0) + +static inline void arch_spin_lock(arch_spinlock_t *lock) +{ + lock->slock = 0; + barrier(); +} + +static inline void +arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) +{ + local_irq_save(flags); + lock->slock = 0; + barrier(); +} + +static inline int arch_spin_trylock(arch_spinlock_t *lock) +{ + char oldval = lock->slock; + + lock->slock = 0; + barrier(); + + return oldval > 0; +} + +static inline void arch_spin_unlock(arch_spinlock_t *lock) +{ + barrier(); + lock->slock = 1; +} + +/* + * Read-write spinlocks. No debug version. + */ +#define arch_read_lock(lock) do { barrier(); (void)(lock); } while (0) +#define arch_write_lock(lock) do { barrier(); (void)(lock); } while (0) +#define arch_read_trylock(lock) ({ barrier(); (void)(lock); 1; }) +#define arch_write_trylock(lock) ({ barrier(); (void)(lock); 1; }) +#define arch_read_unlock(lock) do { barrier(); (void)(lock); } while (0) +#define arch_write_unlock(lock) do { barrier(); (void)(lock); } while (0) + +#else /* DEBUG_SPINLOCK */ +#define arch_spin_is_locked(lock) ((void)(lock), 0) +/* for sched/core.c and kernel_lock.c: */ +# define arch_spin_lock(lock) do { barrier(); (void)(lock); } while (0) +# define arch_spin_lock_flags(lock, flags) do { barrier(); (void)(lock); } while (0) +# define arch_spin_unlock(lock) do { barrier(); (void)(lock); } while (0) +# define arch_spin_trylock(lock) ({ barrier(); (void)(lock); 1; }) +#endif /* DEBUG_SPINLOCK */ + +#define arch_spin_is_contended(lock) (((void)(lock), 0)) + +#define arch_read_can_lock(lock) (((void)(lock), 1)) +#define arch_write_can_lock(lock) (((void)(lock), 1)) + +#define arch_spin_unlock_wait(lock) \ + do { cpu_relax(); } while (arch_spin_is_locked(lock)) + +#endif /* __LINUX_SPINLOCK_UP_H */ |