Commit 715b49ef authored by Alan Cox's avatar Alan Cox Committed by Linus Torvalds
Browse files

[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: default avatarAlan Cox <alan@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 3213e913

drivers/md/kcopyd.c

+1 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 * completion notification.

 */



#include <asm/types.h>

#include <asm/atomic.h>



#include <linux/blkdev.h>

fs/nfsctl.c

+1 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
 *

 */

#include <linux/config.h>

#include <linux/types.h>

#include <linux/file.h>

#include <linux/fs.h>

#include <linux/sunrpc/svc.h>

include/asm-i386/atomic.h

+12 −0
Original line number Diff line number Diff line
@@ -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

include/asm-x86_64/atomic.h

+12 −0
Original line number Diff line number Diff line
@@ -426,5 +426,17 @@ __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(u32 *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

kernel/audit.c

+1 −1
Original line number Diff line number Diff line
@@ -42,8 +42,8 @@ 
 */



#include <linux/init.h>

#include <asm/atomic.h>

#include <asm/types.h>

#include <asm/atomic.h>

#include <linux/mm.h>

#include <linux/module.h>

#include <linux/err.h>

CRA Git | Maintained and supported by SUSTech CRA and CCSE