Prev: [PATCH 1/1] MM: slqb, fix per_cpu access
Next: why kernel implement "udelay" by cpu instructions?
From: Li Zefan on 1 Nov 2009 20:10
I wrote some code which is used as compile-time checker, and the
code should be elided after compile.

So I need to annotate the code as "always unused", compared to
"maybe unused".

Signed-off-by: Li Zefan <lizf(a)cn.fujitsu.com>
---
include/linux/compiler-gcc.h | 1 +
include/linux/compiler.h | 4 ++++
2 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index a3ed7cb..73dcf80 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -79,6 +79,7 @@
#define noinline __attribute__((noinline))
#define __attribute_const__ __attribute__((__const__))
#define __maybe_unused __attribute__((unused))
+#define __always_unused __attribute__((unused))

#define __gcc_header(x) #x
#define _gcc_header(x) __gcc_header(linux/compiler-gcc##x.h)
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index d1cc9f0..1ccebf4 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -132,6 +132,10 @@ extern void __chk_io_ptr(const volatile void __iomem *);
# define __maybe_unused /* unimplemented */
#endif

+#ifndef __always_unused
+# define __always_unused /* unimplemented */
+#endif
+
#ifndef noinline
#define noinline
#endif
--
1.6.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: [PATCH 1/1] MM: slqb, fix per_cpu access
Next: why kernel implement "udelay" by cpu instructions?