[PATCH 8/24] make atomic_read() behave consistently on i386

From: Chris Snook
Date: Thu Aug 09 2007 - 09:50:10 EST


From: Chris Snook <csnook@xxxxxxxxxx>

Make atomic_read() volatile on i386, to ensure memory is actually read
each time.

Signed-off-by: Chris Snook <csnook@xxxxxxxxxx>

--- linux-2.6.23-rc2-orig/include/asm-i386/atomic.h 2007-07-08 19:32:17.000000000 -0400
+++ linux-2.6.23-rc2/include/asm-i386/atomic.h 2007-08-09 06:47:47.000000000 -0400
@@ -25,7 +25,7 @@ typedef struct { int counter; } atomic_t
*
* Atomically reads the value of @v.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)

/**
* atomic_set - set atomic variable
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/