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| author | Alan Cox <alan@lxorguk.ukuu.org.uk> | 2006-01-18 17:44:07 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-01-18 19:20:30 -0800 |
| commit | 715b49ef2de6fcead0776d9349071670282faf65 (patch) | |
| tree | d09b77c804aba3b191dc0ceb294387cf730ede4b /include/asm-i386 | |
| parent | 3213e913b0d6baeb28aa1affbdd4bfa7efedc35f (diff) | |
| download | linux-715b49ef2de6fcead0776d9349071670282faf65.tar.bz2 | |
[PATCH] EDAC: atomic scrub operations
EDAC requires a way to scrub memory if an ECC error is found and the chipset
does not do the work automatically. That means rewriting memory locations
atomically with respect to all CPUs _and_ bus masters. That means we can't
use atomic_add(foo, 0) as it gets optimised for non-SMP
This adds a function to include/asm-foo/atomic.h for the platforms currently
supported which implements a scrub of a mapped block.
It also adjusts a few other files include order where atomic.h is included
before types.h as this now causes an error as atomic_scrub uses u32.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/asm-i386')
| -rw-r--r-- | include/asm-i386/atomic.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/asm-i386/atomic.h b/include/asm-i386/atomic.h index de649d3aa2d4..e2c00c95a5e1 100644 --- a/include/asm-i386/atomic.h +++ b/include/asm-i386/atomic.h @@ -255,5 +255,17 @@ __asm__ __volatile__(LOCK "orl %0,%1" \ #define smp_mb__before_atomic_inc() barrier() #define smp_mb__after_atomic_inc() barrier() +/* ECC atomic, DMA, SMP and interrupt safe scrub function */ + +static __inline__ void atomic_scrub(unsigned long *virt_addr, u32 size) +{ + u32 i; + for (i = 0; i < size / 4; i++, virt_addr++) + /* Very carefully read and write to memory atomically + * so we are interrupt, DMA and SMP safe. + */ + __asm__ __volatile__("lock; addl $0, %0"::"m"(*virt_addr)); +} + #include <asm-generic/atomic.h> #endif |