percpu: remove some sparse warnings
Make the following changes to remove some sparse warnings.
* Make DEFINE_PER_CPU_SECTION() declare __pcpu_unique_* before
defining it.
* Annotate pcpu_extend_area_map() that it is entered with pcpu_lock
held, releases it and then reacquires it.
* Make percpu related macros use unique nested variable names.
* While at it, add pcpu prefix to __size_call[_return]() macros as
to-be-implemented sparse annotations will add percpu specific stuff
to these macros.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index 8b5ec19..0c44196 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -74,31 +74,31 @@
#define percpu_to_op(op, var, val) \
do { \
- typedef typeof(var) T__; \
+ typedef typeof(var) pto_T__; \
if (0) { \
- T__ tmp__; \
- tmp__ = (val); \
+ pto_T__ pto_tmp__; \
+ pto_tmp__ = (val); \
} \
switch (sizeof(var)) { \
case 1: \
asm(op "b %1,"__percpu_arg(0) \
: "+m" (var) \
- : "qi" ((T__)(val))); \
+ : "qi" ((pto_T__)(val))); \
break; \
case 2: \
asm(op "w %1,"__percpu_arg(0) \
: "+m" (var) \
- : "ri" ((T__)(val))); \
+ : "ri" ((pto_T__)(val))); \
break; \
case 4: \
asm(op "l %1,"__percpu_arg(0) \
: "+m" (var) \
- : "ri" ((T__)(val))); \
+ : "ri" ((pto_T__)(val))); \
break; \
case 8: \
asm(op "q %1,"__percpu_arg(0) \
: "+m" (var) \
- : "re" ((T__)(val))); \
+ : "re" ((pto_T__)(val))); \
break; \
default: __bad_percpu_size(); \
} \
@@ -106,31 +106,31 @@
#define percpu_from_op(op, var, constraint) \
({ \
- typeof(var) ret__; \
+ typeof(var) pfo_ret__; \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_arg(1)",%0" \
- : "=q" (ret__) \
+ : "=q" (pfo_ret__) \
: constraint); \
break; \
case 2: \
asm(op "w "__percpu_arg(1)",%0" \
- : "=r" (ret__) \
+ : "=r" (pfo_ret__) \
: constraint); \
break; \
case 4: \
asm(op "l "__percpu_arg(1)",%0" \
- : "=r" (ret__) \
+ : "=r" (pfo_ret__) \
: constraint); \
break; \
case 8: \
asm(op "q "__percpu_arg(1)",%0" \
- : "=r" (ret__) \
+ : "=r" (pfo_ret__) \
: constraint); \
break; \
default: __bad_percpu_size(); \
} \
- ret__; \
+ pfo_ret__; \
})
/*
diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h
index 9bd0319..5a5d6ce 100644
--- a/include/linux/percpu-defs.h
+++ b/include/linux/percpu-defs.h
@@ -60,6 +60,7 @@
#define DEFINE_PER_CPU_SECTION(type, name, sec) \
__PCPU_DUMMY_ATTRS char __pcpu_scope_##name; \
+ extern __PCPU_DUMMY_ATTRS char __pcpu_unique_##name; \
__PCPU_DUMMY_ATTRS char __pcpu_unique_##name; \
__PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES __weak \
__typeof__(type) per_cpu__##name
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 519d687..522f421 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -226,20 +226,20 @@
extern void __bad_size_call_parameter(void);
-#define __size_call_return(stem, variable) \
-({ typeof(variable) ret__; \
+#define __pcpu_size_call_return(stem, variable) \
+({ typeof(variable) pscr_ret__; \
switch(sizeof(variable)) { \
- case 1: ret__ = stem##1(variable);break; \
- case 2: ret__ = stem##2(variable);break; \
- case 4: ret__ = stem##4(variable);break; \
- case 8: ret__ = stem##8(variable);break; \
+ case 1: pscr_ret__ = stem##1(variable);break; \
+ case 2: pscr_ret__ = stem##2(variable);break; \
+ case 4: pscr_ret__ = stem##4(variable);break; \
+ case 8: pscr_ret__ = stem##8(variable);break; \
default: \
__bad_size_call_parameter();break; \
} \
- ret__; \
+ pscr_ret__; \
})
-#define __size_call(stem, variable, ...) \
+#define __pcpu_size_call(stem, variable, ...) \
do { \
switch(sizeof(variable)) { \
case 1: stem##1(variable, __VA_ARGS__);break; \
@@ -299,7 +299,7 @@
# ifndef this_cpu_read_8
# define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
# endif
-# define this_cpu_read(pcp) __size_call_return(this_cpu_read_, (pcp))
+# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
#endif
#define _this_cpu_generic_to_op(pcp, val, op) \
@@ -322,7 +322,7 @@
# ifndef this_cpu_write_8
# define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
-# define this_cpu_write(pcp, val) __size_call(this_cpu_write_, (pcp), (val))
+# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
#endif
#ifndef this_cpu_add
@@ -338,7 +338,7 @@
# ifndef this_cpu_add_8
# define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
-# define this_cpu_add(pcp, val) __size_call(this_cpu_add_, (pcp), (val))
+# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
#endif
#ifndef this_cpu_sub
@@ -366,7 +366,7 @@
# ifndef this_cpu_and_8
# define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
-# define this_cpu_and(pcp, val) __size_call(this_cpu_and_, (pcp), (val))
+# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
#endif
#ifndef this_cpu_or
@@ -382,7 +382,7 @@
# ifndef this_cpu_or_8
# define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
-# define this_cpu_or(pcp, val) __size_call(this_cpu_or_, (pcp), (val))
+# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
#endif
#ifndef this_cpu_xor
@@ -398,7 +398,7 @@
# ifndef this_cpu_xor_8
# define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
# endif
-# define this_cpu_xor(pcp, val) __size_call(this_cpu_or_, (pcp), (val))
+# define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
#endif
/*
@@ -428,7 +428,7 @@
# ifndef __this_cpu_read_8
# define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp)))
# endif
-# define __this_cpu_read(pcp) __size_call_return(__this_cpu_read_, (pcp))
+# define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp))
#endif
#define __this_cpu_generic_to_op(pcp, val, op) \
@@ -449,7 +449,7 @@
# ifndef __this_cpu_write_8
# define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
# endif
-# define __this_cpu_write(pcp, val) __size_call(__this_cpu_write_, (pcp), (val))
+# define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val))
#endif
#ifndef __this_cpu_add
@@ -465,7 +465,7 @@
# ifndef __this_cpu_add_8
# define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
# endif
-# define __this_cpu_add(pcp, val) __size_call(__this_cpu_add_, (pcp), (val))
+# define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val))
#endif
#ifndef __this_cpu_sub
@@ -493,7 +493,7 @@
# ifndef __this_cpu_and_8
# define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
# endif
-# define __this_cpu_and(pcp, val) __size_call(__this_cpu_and_, (pcp), (val))
+# define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val))
#endif
#ifndef __this_cpu_or
@@ -509,7 +509,7 @@
# ifndef __this_cpu_or_8
# define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
# endif
-# define __this_cpu_or(pcp, val) __size_call(__this_cpu_or_, (pcp), (val))
+# define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val))
#endif
#ifndef __this_cpu_xor
@@ -525,7 +525,7 @@
# ifndef __this_cpu_xor_8
# define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
# endif
-# define __this_cpu_xor(pcp, val) __size_call(__this_cpu_xor_, (pcp), (val))
+# define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
#endif
/*
@@ -556,7 +556,7 @@
# ifndef irqsafe_cpu_add_8
# define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
# endif
-# define irqsafe_cpu_add(pcp, val) __size_call(irqsafe_cpu_add_, (pcp), (val))
+# define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
#endif
#ifndef irqsafe_cpu_sub
@@ -584,7 +584,7 @@
# ifndef irqsafe_cpu_and_8
# define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
# endif
-# define irqsafe_cpu_and(pcp, val) __size_call(irqsafe_cpu_and_, (val))
+# define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
#endif
#ifndef irqsafe_cpu_or
@@ -600,7 +600,7 @@
# ifndef irqsafe_cpu_or_8
# define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
# endif
-# define irqsafe_cpu_or(pcp, val) __size_call(irqsafe_cpu_or_, (val))
+# define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
#endif
#ifndef irqsafe_cpu_xor
@@ -616,7 +616,7 @@
# ifndef irqsafe_cpu_xor_8
# define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
# endif
-# define irqsafe_cpu_xor(pcp, val) __size_call(irqsafe_cpu_xor_, (val))
+# define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
#endif
#endif /* __LINUX_PERCPU_H */
diff --git a/mm/percpu.c b/mm/percpu.c
index ec158bb..e2e80fc 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -365,6 +365,7 @@
* 0 if noop, 1 if successfully extended, -errno on failure.
*/
static int pcpu_extend_area_map(struct pcpu_chunk *chunk)
+ __releases(lock) __acquires(lock)
{
int new_alloc;
int *new;