2010-08-06 18:27:11

by Namhyung Kim

Subject: [PATCH 1/5] percpu: add sanity check for UP

add sanity check for percpu accessors on UP.
This removes lots of sparse warnings.

Signed-off-by: Namhyung Kim <[email protected]>
---
include/asm-generic/percpu.h | 12 +++++++++---
include/linux/percpu.h | 2 +-
2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index b5043a9..50ac3ac 100644
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -70,9 +70,15 @@ extern void setup_per_cpu_areas(void);

#else /* ! SMP */

-#define per_cpu(var, cpu) (*((void)(cpu), &(var)))
-#define __get_cpu_var(var) (var)
-#define __raw_get_cpu_var(var) (var)
+#define VERIFY_PERCPU_PTR(__p) ({ \
+ __verify_pcpu_ptr((__p)); \
+ (typeof(*(__p)) __kernel __force *) (__p); \
+})
+
+#define per_cpu(var, cpu) \
+ (*((void)(cpu), VERIFY_PERCPU_PTR(&(var))))
+#define __get_cpu_var(var) (*VERIFY_PERCPU_PTR(&(var)))
+#define __raw_get_cpu_var(var) (*VERIFY_PERCPU_PTR(&(var)))
#define this_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
#define __this_cpu_ptr(ptr) this_cpu_ptr(ptr)

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index d3a38d6..bc36301 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -143,7 +143,7 @@ extern void __init setup_per_cpu_areas(void);

#else /* CONFIG_SMP */

-#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
+#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })

/* can't distinguish from other static vars, always false */
static inline bool is_kernel_percpu_address(unsigned long addr)
--
1.7.0.4

2010-08-07 12:25:47

by Tejun Heo

Subject: percpu: handle __percpu notations in UP accessors

>From 18cb2aef91b37dbce2bec2f39bb1dddd0e9dd838 Mon Sep 17 00:00:00 2001
From: Namhyung Kim <[email protected]>
Date: Sat, 7 Aug 2010 03:26:23 +0900

UP accessors didn't take care of __percpu notations leading to a lot
of spurious sparse warnings on UP configurations. Fix it.

Signed-off-by: Namhyung Kim <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
---
Applied to wq#for-next w/ slight commit description and whitespace
updates.

Thanks.

include/asm-generic/percpu.h | 15 ++++++++++-----
include/linux/percpu.h | 2 +-
2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index b5043a9..08923b6 100644
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -70,11 +70,16 @@ extern void setup_per_cpu_areas(void);

#else /* ! SMP */

-#define per_cpu(var, cpu) (*((void)(cpu), &(var)))
-#define __get_cpu_var(var) (var)
-#define __raw_get_cpu_var(var) (var)
-#define this_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
-#define __this_cpu_ptr(ptr) this_cpu_ptr(ptr)
+#define VERIFY_PERCPU_PTR(__p) ({ \
+ __verify_pcpu_ptr((__p)); \
+ (typeof(*(__p)) __kernel __force *)(__p); \
+})
+
+#define per_cpu(var, cpu) (*((void)(cpu), VERIFY_PERCPU_PTR(&(var))))
+#define __get_cpu_var(var) (*VERIFY_PERCPU_PTR(&(var)))
+#define __raw_get_cpu_var(var) (*VERIFY_PERCPU_PTR(&(var)))
+#define this_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
+#define __this_cpu_ptr(ptr) this_cpu_ptr(ptr)

#endif /* SMP */

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index b8b9084..49466b1 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -149,7 +149,7 @@ extern void __init percpu_init_late(void);

#else /* CONFIG_SMP */

-#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
+#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })

/* can't distinguish from other static vars, always false */
static inline bool is_kernel_percpu_address(unsigned long addr)
--
1.7.1