[PATCH 5/24] make atomic_read() behave consistently on cris
From: Chris Snook <hidden>
Date: 2007-08-09 14:18:10
Also in:
linux-arch, lkml
From: Chris Snook <redacted> Purify volatile use for atomic_t on cris. Signed-off-by: Chris Snook <redacted>
--- linux-2.6.23-rc2-orig/include/asm-cris/atomic.h 2007-07-08 19:32:17.000000000 -0400
+++ linux-2.6.23-rc2/include/asm-cris/atomic.h 2007-08-09 06:38:28.000000000 -0400@@ -11,11 +11,15 @@ * resource counting etc.. */ -typedef struct { volatile int counter; } atomic_t; +typedef struct { int counter; } atomic_t; #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) ((v)->counter) +/* + * Casting to volatile here minimizes the need for barriers, + * without having to declare the type itself as volatile. + */ +#define atomic_read(v) (*(volatile int *)&(v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) /* These should be written in asm but we do it in C for now. */