diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/blackfin/include/asm/barrier.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/arch/blackfin/include/asm/barrier.h')
-rw-r--r-- | kernel/arch/blackfin/include/asm/barrier.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/kernel/arch/blackfin/include/asm/barrier.h b/kernel/arch/blackfin/include/asm/barrier.h new file mode 100644 index 000000000..dfb66fe88 --- /dev/null +++ b/kernel/arch/blackfin/include/asm/barrier.h @@ -0,0 +1,86 @@ +/* + * Copyright 2004-2009 Analog Devices Inc. + * Tony Kou (tonyko@lineo.ca) + * + * Licensed under the GPL-2 or later + */ + +#ifndef _BLACKFIN_BARRIER_H +#define _BLACKFIN_BARRIER_H + +#include <asm/cache.h> + +#define nop() __asm__ __volatile__ ("nop;\n\t" : : ) + +/* + * Force strict CPU ordering. + */ +#ifdef CONFIG_SMP + +#ifdef __ARCH_SYNC_CORE_DCACHE +/* Force Core data cache coherence */ +# define mb() do { barrier(); smp_check_barrier(); smp_mark_barrier(); } while (0) +# define rmb() do { barrier(); smp_check_barrier(); } while (0) +# define wmb() do { barrier(); smp_mark_barrier(); } while (0) +/* + * read_barrier_depends - Flush all pending reads that subsequents reads + * depend on. + * + * No data-dependent reads from memory-like regions are ever reordered + * over this barrier. All reads preceding this primitive are guaranteed + * to access memory (but not necessarily other CPUs' caches) before any + * reads following this primitive that depend on the data return by + * any of the preceding reads. This primitive is much lighter weight than + * rmb() on most CPUs, and is never heavier weight than is + * rmb(). + * + * These ordering constraints are respected by both the local CPU + * and the compiler. + * + * Ordering is not guaranteed by anything other than these primitives, + * not even by data dependencies. See the documentation for + * memory_barrier() for examples and URLs to more information. + * + * For example, the following code would force ordering (the initial + * value of "a" is zero, "b" is one, and "p" is "&a"): + * + * <programlisting> + * CPU 0 CPU 1 + * + * b = 2; + * memory_barrier(); + * p = &b; q = p; + * read_barrier_depends(); + * d = *q; + * </programlisting> + * + * because the read of "*q" depends on the read of "p" and these + * two reads are separated by a read_barrier_depends(). However, + * the following code, with the same initial values for "a" and "b": + * + * <programlisting> + * CPU 0 CPU 1 + * + * a = 2; + * memory_barrier(); + * b = 3; y = b; + * read_barrier_depends(); + * x = a; + * </programlisting> + * + * does not enforce ordering, since there is no data dependency between + * the read of "a" and the read of "b". Therefore, on some CPUs, such + * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb() + * in cases like this where there are no data dependencies. + */ +# define read_barrier_depends() do { barrier(); smp_check_barrier(); } while (0) +#endif + +#endif /* !CONFIG_SMP */ + +#define smp_mb__before_atomic() barrier() +#define smp_mb__after_atomic() barrier() + +#include <asm-generic/barrier.h> + +#endif /* _BLACKFIN_BARRIER_H */ |