From dd17c8f72993f9461e9c19250e3f155d6d99df22 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 29 Oct 2009 22:34:15 +0900 Subject: percpu: remove per_cpu__ prefix. Now that the return from alloc_percpu is compatible with the address of per-cpu vars, it makes sense to hand around the address of per-cpu variables. To make this sane, we remove the per_cpu__ prefix we used created to stop people accidentally using these vars directly. Now we have sparse, we can use that (next patch). tj: * Updated to convert stuff which were missed by or added after the original patch. * Kill per_cpu_var() macro. Signed-off-by: Rusty Russell Signed-off-by: Tejun Heo Reviewed-by: Christoph Lameter --- include/asm-generic/percpu.h | 12 ++++++------ include/linux/percpu-defs.h | 18 ++++++------------ include/linux/percpu.h | 5 ++--- include/linux/vmstat.h | 8 ++++---- 4 files changed, 18 insertions(+), 25 deletions(-) (limited to 'include') diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index 8087b90d467..ca6f0491412 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -50,11 +50,11 @@ extern unsigned long __per_cpu_offset[NR_CPUS]; * offset. */ #define per_cpu(var, cpu) \ - (*SHIFT_PERCPU_PTR(&per_cpu_var(var), per_cpu_offset(cpu))) + (*SHIFT_PERCPU_PTR(&(var), per_cpu_offset(cpu))) #define __get_cpu_var(var) \ - (*SHIFT_PERCPU_PTR(&per_cpu_var(var), my_cpu_offset)) + (*SHIFT_PERCPU_PTR(&(var), my_cpu_offset)) #define __raw_get_cpu_var(var) \ - (*SHIFT_PERCPU_PTR(&per_cpu_var(var), __my_cpu_offset)) + (*SHIFT_PERCPU_PTR(&(var), __my_cpu_offset)) #define this_cpu_ptr(ptr) SHIFT_PERCPU_PTR(ptr, my_cpu_offset) #define __this_cpu_ptr(ptr) SHIFT_PERCPU_PTR(ptr, __my_cpu_offset) @@ -66,9 +66,9 @@ extern void setup_per_cpu_areas(void); #else /* ! SMP */ -#define per_cpu(var, cpu) (*((void)(cpu), &per_cpu_var(var))) -#define __get_cpu_var(var) per_cpu_var(var) -#define __raw_get_cpu_var(var) per_cpu_var(var) +#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) diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index 5a5d6ce4bd5..ee99f6c2cdc 100644 --- a/include/linux/percpu-defs.h +++ b/include/linux/percpu-defs.h @@ -1,12 +1,6 @@ #ifndef _LINUX_PERCPU_DEFS_H #define _LINUX_PERCPU_DEFS_H -/* - * Determine the real variable name from the name visible in the - * kernel sources. - */ -#define per_cpu_var(var) per_cpu__##var - /* * Base implementations of per-CPU variable declarations and definitions, where * the section in which the variable is to be placed is provided by the @@ -56,24 +50,24 @@ */ #define DECLARE_PER_CPU_SECTION(type, name, sec) \ extern __PCPU_DUMMY_ATTRS char __pcpu_scope_##name; \ - extern __PCPU_ATTRS(sec) __typeof__(type) per_cpu__##name + extern __PCPU_ATTRS(sec) __typeof__(type) name #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 + __typeof__(type) name #else /* * Normal declaration and definition macros. */ #define DECLARE_PER_CPU_SECTION(type, name, sec) \ - extern __PCPU_ATTRS(sec) __typeof__(type) per_cpu__##name + extern __PCPU_ATTRS(sec) __typeof__(type) name #define DEFINE_PER_CPU_SECTION(type, name, sec) \ __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES \ - __typeof__(type) per_cpu__##name + __typeof__(type) name #endif /* @@ -137,8 +131,8 @@ /* * Intermodule exports for per-CPU variables. */ -#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var) -#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var) +#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(var) +#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(var) #endif /* _LINUX_PERCPU_DEFS_H */ diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 522f421ec21..e12410e55e0 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -182,7 +182,7 @@ static inline void *pcpu_lpage_remapped(void *kaddr) #ifndef percpu_read # define percpu_read(var) \ ({ \ - typeof(per_cpu_var(var)) __tmp_var__; \ + typeof(var) __tmp_var__; \ __tmp_var__ = get_cpu_var(var); \ put_cpu_var(var); \ __tmp_var__; \ @@ -253,8 +253,7 @@ do { \ /* * Optimized manipulation for memory allocated through the per cpu - * allocator or for addresses of per cpu variables (can be determined - * using per_cpu_var(xx). + * allocator or for addresses of per cpu variables. * * These operation guarantee exclusivity of access for other operations * on the *same* processor. The assumption is that per cpu data is only diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index d85889710f9..3e489fda11a 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -76,22 +76,22 @@ DECLARE_PER_CPU(struct vm_event_state, vm_event_states); static inline void __count_vm_event(enum vm_event_item item) { - __this_cpu_inc(per_cpu_var(vm_event_states).event[item]); + __this_cpu_inc(vm_event_states.event[item]); } static inline void count_vm_event(enum vm_event_item item) { - this_cpu_inc(per_cpu_var(vm_event_states).event[item]); + this_cpu_inc(vm_event_states.event[item]); } static inline void __count_vm_events(enum vm_event_item item, long delta) { - __this_cpu_add(per_cpu_var(vm_event_states).event[item], delta); + __this_cpu_add(vm_event_states.event[item], delta); } static inline void count_vm_events(enum vm_event_item item, long delta) { - this_cpu_add(per_cpu_var(vm_event_states).event[item], delta); + this_cpu_add(vm_event_states.event[item], delta); } extern void all_vm_events(unsigned long *); -- cgit v1.2.3 From f7b64fe806029e0a0454df132eec3c5ab576102c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 29 Oct 2009 22:34:15 +0900 Subject: percpu: make access macros universal Now that per_cpu__ prefix is gone, there's no distinction between static and dynamic percpu variables. Make get_cpu_var() take dynamic percpu variables and ensure that all macros have parentheses around the parameter evaluation and evaluate the variable parameter only once such that any expression which evaluates to percpu address can be used safely. Signed-off-by: Tejun Heo --- include/linux/percpu.h | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'include') diff --git a/include/linux/percpu.h b/include/linux/percpu.h index e12410e55e0..f965f833a64 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -27,10 +27,13 @@ * we force a syntax error here if it isn't. */ #define get_cpu_var(var) (*({ \ - extern int simple_identifier_##var(void); \ preempt_disable(); \ &__get_cpu_var(var); })) -#define put_cpu_var(var) preempt_enable() + +#define put_cpu_var(var) do { \ + (void)(var); \ + preempt_enable(); \ +} while (0) #ifdef CONFIG_SMP @@ -182,17 +185,19 @@ static inline void *pcpu_lpage_remapped(void *kaddr) #ifndef percpu_read # define percpu_read(var) \ ({ \ - typeof(var) __tmp_var__; \ - __tmp_var__ = get_cpu_var(var); \ - put_cpu_var(var); \ - __tmp_var__; \ + typeof(var) *pr_ptr__ = &(var); \ + typeof(var) pr_ret__; \ + pr_ret__ = get_cpu_var(*pr_ptr__); \ + put_cpu_var(*pr_ptr__); \ + pr_ret__; \ }) #endif #define __percpu_generic_to_op(var, val, op) \ do { \ - get_cpu_var(var) op val; \ - put_cpu_var(var); \ + typeof(var) *pgto_ptr__ = &(var); \ + get_cpu_var(*pgto_ptr__) op val; \ + put_cpu_var(*pgto_ptr__); \ } while (0) #ifndef percpu_write @@ -304,7 +309,7 @@ do { \ #define _this_cpu_generic_to_op(pcp, val, op) \ do { \ preempt_disable(); \ - *__this_cpu_ptr(&pcp) op val; \ + *__this_cpu_ptr(&(pcp)) op val; \ preempt_enable(); \ } while (0) -- cgit v1.2.3 From e0fdb0e050eae331046385643618f12452aa7e73 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 29 Oct 2009 22:34:15 +0900 Subject: percpu: add __percpu for sparse. We have to make __kernel "__attribute__((address_space(0)))" so we can cast to it. tj: * put_cpu_var() update. * Annotations added to dynamic allocator interface. Signed-off-by: Rusty Russell Cc: Al Viro Signed-off-by: Tejun Heo --- include/asm-generic/percpu.h | 4 +++- include/linux/compiler.h | 4 +++- include/linux/percpu-defs.h | 2 +- include/linux/percpu.h | 18 +++++++++++------- 4 files changed, 18 insertions(+), 10 deletions(-) (limited to 'include') diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index ca6f0491412..fded453fd25 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -41,7 +41,9 @@ extern unsigned long __per_cpu_offset[NR_CPUS]; * Only S390 provides its own means of moving the pointer. */ #ifndef SHIFT_PERCPU_PTR -#define SHIFT_PERCPU_PTR(__p, __offset) RELOC_HIDE((__p), (__offset)) +/* Weird cast keeps both GCC and sparse happy. */ +#define SHIFT_PERCPU_PTR(__p, __offset) \ + RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)) #endif /* diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 04fb5135b4e..abba8045c6e 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -5,7 +5,7 @@ #ifdef __CHECKER__ # define __user __attribute__((noderef, address_space(1))) -# define __kernel /* default address space */ +# define __kernel __attribute__((address_space(0))) # define __safe __attribute__((safe)) # define __force __attribute__((force)) # define __nocast __attribute__((nocast)) @@ -15,6 +15,7 @@ # define __acquire(x) __context__(x,1) # define __release(x) __context__(x,-1) # define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) +# define __percpu __attribute__((noderef, address_space(3))) extern void __chk_user_ptr(const volatile void __user *); extern void __chk_io_ptr(const volatile void __iomem *); #else @@ -32,6 +33,7 @@ extern void __chk_io_ptr(const volatile void __iomem *); # define __acquire(x) (void)0 # define __release(x) (void)0 # define __cond_lock(x,c) (c) +# define __percpu #endif #ifdef __KERNEL__ diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index ee99f6c2cdc..0fa0cb52425 100644 --- a/include/linux/percpu-defs.h +++ b/include/linux/percpu-defs.h @@ -12,7 +12,7 @@ * that section. */ #define __PCPU_ATTRS(sec) \ - __attribute__((section(PER_CPU_BASE_SECTION sec))) \ + __percpu __attribute__((section(PER_CPU_BASE_SECTION sec))) \ PER_CPU_ATTRIBUTES #define __PCPU_DUMMY_ATTRS \ diff --git a/include/linux/percpu.h b/include/linux/percpu.h index f965f833a64..2c0d31a3f6b 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -30,8 +30,12 @@ preempt_disable(); \ &__get_cpu_var(var); })) +/* + * The weird & is necessary because sparse considers (void)(var) to be + * a direct dereference of percpu variable (var). + */ #define put_cpu_var(var) do { \ - (void)(var); \ + (void)&(var); \ preempt_enable(); \ } while (0) @@ -130,9 +134,9 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size, */ #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) -extern void *__alloc_reserved_percpu(size_t size, size_t align); -extern void *__alloc_percpu(size_t size, size_t align); -extern void free_percpu(void *__pdata); +extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); +extern void __percpu *__alloc_percpu(size_t size, size_t align); +extern void free_percpu(void __percpu *__pdata); #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA extern void __init setup_per_cpu_areas(void); @@ -142,7 +146,7 @@ extern void __init setup_per_cpu_areas(void); #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) -static inline void *__alloc_percpu(size_t size, size_t align) +static inline void __percpu *__alloc_percpu(size_t size, size_t align) { /* * Can't easily make larger alignment work with kmalloc. WARN @@ -153,7 +157,7 @@ static inline void *__alloc_percpu(size_t size, size_t align) return kzalloc(size, GFP_KERNEL); } -static inline void free_percpu(void *p) +static inline void free_percpu(void __percpu *p) { kfree(p); } @@ -168,7 +172,7 @@ static inline void *pcpu_lpage_remapped(void *kaddr) #endif /* CONFIG_SMP */ #define alloc_percpu(type) \ - (typeof(type) *)__alloc_percpu(sizeof(type), __alignof__(type)) + (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type)) /* * Optional methods for optimized non-lvalue per-cpu variable access. -- cgit v1.2.3 From 545695fb41da117928ab946067a42d9e15fd009d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 29 Oct 2009 22:34:15 +0900 Subject: percpu: make accessors check for percpu pointer in sparse The previous patch made sparse warn about percpu variables being used directly without going through percpu accessors. This patch implements the other half - checking whether non percpu variable is passed into percpu accessors. Signed-off-by: Tejun Heo Cc: Rusty Russell Cc: Al Viro --- include/asm-generic/percpu.h | 6 ++++-- include/linux/percpu-defs.h | 20 ++++++++++++++++++-- include/linux/percpu.h | 2 ++ 3 files changed, 24 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index fded453fd25..04f91c2d3f7 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -42,8 +42,10 @@ extern unsigned long __per_cpu_offset[NR_CPUS]; */ #ifndef SHIFT_PERCPU_PTR /* Weird cast keeps both GCC and sparse happy. */ -#define SHIFT_PERCPU_PTR(__p, __offset) \ - RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)) +#define SHIFT_PERCPU_PTR(__p, __offset) ({ \ + __verify_pcpu_ptr((__p)); \ + RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)); \ +}) #endif /* diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index 0fa0cb52425..1fa36eb54b6 100644 --- a/include/linux/percpu-defs.h +++ b/include/linux/percpu-defs.h @@ -18,6 +18,16 @@ #define __PCPU_DUMMY_ATTRS \ __attribute__((section(".discard"), unused)) +/* + * Macro which verifies @ptr is a percpu pointer without evaluating + * @ptr. This is to be used in percpu accessors to verify that the + * input parameter is a percpu pointer. + */ +#define __verify_pcpu_ptr(ptr) do { \ + void __percpu *__vpp_verify = (typeof(ptr))NULL; \ + (void)__vpp_verify; \ +} while (0) + /* * s390 and alpha modules require percpu variables to be defined as * weak to force the compiler to generate GOT based external @@ -129,10 +139,16 @@ __aligned(PAGE_SIZE) /* - * Intermodule exports for per-CPU variables. + * Intermodule exports for per-CPU variables. sparse forgets about + * address space across EXPORT_SYMBOL(), change EXPORT_SYMBOL() to + * noop if __CHECKER__. */ +#ifndef __CHECKER__ #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(var) #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(var) - +#else +#define EXPORT_PER_CPU_SYMBOL(var) +#define EXPORT_PER_CPU_SYMBOL_GPL(var) +#endif #endif /* _LINUX_PERCPU_DEFS_H */ diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 2c0d31a3f6b..42878f0cd0e 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -237,6 +237,7 @@ extern void __bad_size_call_parameter(void); #define __pcpu_size_call_return(stem, variable) \ ({ typeof(variable) pscr_ret__; \ + __verify_pcpu_ptr(&(variable)); \ switch(sizeof(variable)) { \ case 1: pscr_ret__ = stem##1(variable);break; \ case 2: pscr_ret__ = stem##2(variable);break; \ @@ -250,6 +251,7 @@ extern void __bad_size_call_parameter(void); #define __pcpu_size_call(stem, variable, ...) \ do { \ + __verify_pcpu_ptr(&(variable)); \ switch(sizeof(variable)) { \ case 1: stem##1(variable, __VA_ARGS__);break; \ case 2: stem##2(variable, __VA_ARGS__);break; \ -- cgit v1.2.3 From 85438592f179c126ad4cb9a280046d4f0a501e6d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 18 Nov 2009 17:53:21 +0900 Subject: percpu: remove compile warnings caused by __verify_pcpu_ptr() If percpu pointer is const, __verify_pcpu_ptr() triggers warnings like the following. drivers/net/loopback.c: In function 'loopback_get_stats': drivers/net/loopback.c:109: warning: initialization discards qualifiers from pointer target type Fix it by adding const to the verification target pointer used in __verify_pcpu_ptr(). Signed-off-by: Tejun Heo Reported-by: Stephen Rothwell --- include/linux/percpu-defs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index 1fa36eb54b6..68567c0b3a5 100644 --- a/include/linux/percpu-defs.h +++ b/include/linux/percpu-defs.h @@ -24,7 +24,7 @@ * input parameter is a percpu pointer. */ #define __verify_pcpu_ptr(ptr) do { \ - void __percpu *__vpp_verify = (typeof(ptr))NULL; \ + const void __percpu *__vpp_verify = (typeof(ptr))NULL; \ (void)__vpp_verify; \ } while (0) -- cgit v1.2.3 From 38b7827fcdd660f591d645bd3ae6644456a4773c Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Tue, 5 Jan 2010 15:34:49 +0900 Subject: local_t: Remove cpu_local_xx macros These macros have not been used for awhile now. Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo --- include/asm-generic/local.h | 19 ------------------- 1 file changed, 19 deletions(-) (limited to 'include') diff --git a/include/asm-generic/local.h b/include/asm-generic/local.h index fc218444e31..c8a5d68541d 100644 --- a/include/asm-generic/local.h +++ b/include/asm-generic/local.h @@ -52,23 +52,4 @@ typedef struct #define __local_add(i,l) local_set((l), local_read(l) + (i)) #define __local_sub(i,l) local_set((l), local_read(l) - (i)) -/* Use these for per-cpu local_t variables: on some archs they are - * much more efficient than these naive implementations. Note they take - * a variable (eg. mystruct.foo), not an address. - */ -#define cpu_local_read(l) local_read(&__get_cpu_var(l)) -#define cpu_local_set(l, i) local_set(&__get_cpu_var(l), (i)) -#define cpu_local_inc(l) local_inc(&__get_cpu_var(l)) -#define cpu_local_dec(l) local_dec(&__get_cpu_var(l)) -#define cpu_local_add(i, l) local_add((i), &__get_cpu_var(l)) -#define cpu_local_sub(i, l) local_sub((i), &__get_cpu_var(l)) - -/* Non-atomic increments, ie. preemption disabled and won't be touched - * in interrupt, etc. Some archs can optimize this case well. - */ -#define __cpu_local_inc(l) __local_inc(&__get_cpu_var(l)) -#define __cpu_local_dec(l) __local_dec(&__get_cpu_var(l)) -#define __cpu_local_add(i, l) __local_add((i), &__get_cpu_var(l)) -#define __cpu_local_sub(i, l) __local_sub((i), &__get_cpu_var(l)) - #endif /* _ASM_GENERIC_LOCAL_H */ -- cgit v1.2.3 From e1783a240f491fb233f04edc042e16b18a7a79ba Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Tue, 5 Jan 2010 15:34:50 +0900 Subject: module: Use this_cpu_xx to dynamically allocate counters Use cpu ops to deal with the per cpu data instead of a local_t. Reduces memory requirements, cache footprint and decreases cycle counts. The this_cpu_xx operations are also used for !SMP mode. Otherwise we could not drop the use of __module_ref_addr() which would make per cpu data handling complicated. this_cpu_xx operations have their own fallback for !SMP. V8-V9: - Leave include asm/module.h since ringbuffer.c depends on it. Nothing else does though. Another patch will deal with that. - Remove spurious free. Signed-off-by: Christoph Lameter Acked-by: Rusty Russell Signed-off-by: Tejun Heo --- include/linux/module.h | 36 ++++++++++++++---------------------- 1 file changed, 14 insertions(+), 22 deletions(-) (limited to 'include') diff --git a/include/linux/module.h b/include/linux/module.h index 6cb1a3cab5d..2302f09ea2d 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -18,6 +18,7 @@ #include #include +#include #include #include @@ -363,11 +364,9 @@ struct module /* Destruction function. */ void (*exit)(void); -#ifdef CONFIG_SMP - char *refptr; -#else - local_t ref; -#endif + struct module_ref { + int count; + } *refptr; #endif #ifdef CONFIG_CONSTRUCTORS @@ -454,25 +453,16 @@ void __symbol_put(const char *symbol); #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x) void symbol_put_addr(void *addr); -static inline local_t *__module_ref_addr(struct module *mod, int cpu) -{ -#ifdef CONFIG_SMP - return (local_t *) (mod->refptr + per_cpu_offset(cpu)); -#else - return &mod->ref; -#endif -} - /* Sometimes we know we already have a refcount, and it's easier not to handle the error case (which only happens with rmmod --wait). */ static inline void __module_get(struct module *module) { if (module) { - unsigned int cpu = get_cpu(); - local_inc(__module_ref_addr(module, cpu)); + preempt_disable(); + __this_cpu_inc(module->refptr->count); trace_module_get(module, _THIS_IP_, - local_read(__module_ref_addr(module, cpu))); - put_cpu(); + __this_cpu_read(module->refptr->count)); + preempt_enable(); } } @@ -481,15 +471,17 @@ static inline int try_module_get(struct module *module) int ret = 1; if (module) { - unsigned int cpu = get_cpu(); + preempt_disable(); + if (likely(module_is_live(module))) { - local_inc(__module_ref_addr(module, cpu)); + __this_cpu_inc(module->refptr->count); trace_module_get(module, _THIS_IP_, - local_read(__module_ref_addr(module, cpu))); + __this_cpu_read(module->refptr->count)); } else ret = 0; - put_cpu(); + + preempt_enable(); } return ret; } -- cgit v1.2.3 From 79615760f380ec86cd58204744e774c33fab9211 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Tue, 5 Jan 2010 15:34:50 +0900 Subject: local_t: Move local.h include to ringbuffer.c and ring_buffer_benchmark.c ringbuffer*.c are the last users of local.h. Remove the include from modules.h and add it to ringbuffer files. Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo --- include/linux/module.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/linux/module.h b/include/linux/module.h index 2302f09ea2d..7e74ae0051c 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -17,7 +17,6 @@ #include #include -#include #include #include -- cgit v1.2.3 From 99dcc3e5a94ed491fbef402831d8c0bbb267f995 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Tue, 5 Jan 2010 15:34:51 +0900 Subject: this_cpu: Page allocator conversion Use the per cpu allocator functionality to avoid per cpu arrays in struct zone. This drastically reduces the size of struct zone for systems with large amounts of processors and allows placement of critical variables of struct zone in one cacheline even on very large systems. Another effect is that the pagesets of one processor are placed near one another. If multiple pagesets from different zones fit into one cacheline then additional cacheline fetches can be avoided on the hot paths when allocating memory from multiple zones. Bootstrap becomes simpler if we use the same scheme for UP, SMP, NUMA. #ifdefs are reduced and we can drop the zone_pcp macro. Hotplug handling is also simplified since cpu alloc can bring up and shut down cpu areas for a specific cpu as a whole. So there is no need to allocate or free individual pagesets. V7-V8: - Explain chicken egg dilemmna with percpu allocator. V4-V5: - Fix up cases where per_cpu_ptr is called before irq disable - Integrate the bootstrap logic that was separate before. tj: Build failure in pageset_cpuup_callback() due to missing ret variable fixed. Reviewed-by: Mel Gorman Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo --- include/linux/mm.h | 4 ---- include/linux/mmzone.h | 12 ++---------- 2 files changed, 2 insertions(+), 14 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 2265f28eb47..554fa395aac 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1079,11 +1079,7 @@ extern void si_meminfo(struct sysinfo * val); extern void si_meminfo_node(struct sysinfo *val, int nid); extern int after_bootmem; -#ifdef CONFIG_NUMA extern void setup_per_cpu_pageset(void); -#else -static inline void setup_per_cpu_pageset(void) {} -#endif extern void zone_pcp_update(struct zone *zone); diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 30fe668c254..7874201a355 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -184,13 +184,7 @@ struct per_cpu_pageset { s8 stat_threshold; s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS]; #endif -} ____cacheline_aligned_in_smp; - -#ifdef CONFIG_NUMA -#define zone_pcp(__z, __cpu) ((__z)->pageset[(__cpu)]) -#else -#define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)]) -#endif +}; #endif /* !__GENERATING_BOUNDS.H */ @@ -306,10 +300,8 @@ struct zone { */ unsigned long min_unmapped_pages; unsigned long min_slab_pages; - struct per_cpu_pageset *pageset[NR_CPUS]; -#else - struct per_cpu_pageset pageset[NR_CPUS]; #endif + struct per_cpu_pageset *pageset; /* * free areas of different sizes */ -- cgit v1.2.3 From 43cf38eb5cea91245502df3fcee4dbfc1c74dd1c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 2 Feb 2010 14:38:57 +0900 Subject: percpu: add __percpu sparse annotations to core kernel subsystems Add __percpu sparse annotations to core subsystems. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: Tejun Heo Reviewed-by: Christoph Lameter Acked-by: Paul E. McKenney Cc: Jens Axboe Cc: linux-mm@kvack.org Cc: Rusty Russell Cc: Dipankar Sarma Cc: Peter Zijlstra Cc: Andrew Morton Cc: Eric Biederman --- include/linux/blktrace_api.h | 4 ++-- include/linux/genhd.h | 2 +- include/linux/kexec.h | 2 +- include/linux/mmzone.h | 2 +- include/linux/module.h | 2 +- include/linux/percpu_counter.h | 2 +- include/linux/srcu.h | 2 +- 7 files changed, 8 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 3b73b9992b2..416bf62d6d4 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -150,8 +150,8 @@ struct blk_user_trace_setup { struct blk_trace { int trace_state; struct rchan *rchan; - unsigned long *sequence; - unsigned char *msg_data; + unsigned long __percpu *sequence; + unsigned char __percpu *msg_data; u16 act_mask; u64 start_lba; u64 end_lba; diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 9717081c75a..56b50514ab2 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -101,7 +101,7 @@ struct hd_struct { unsigned long stamp; int in_flight[2]; #ifdef CONFIG_SMP - struct disk_stats *dkstats; + struct disk_stats __percpu *dkstats; #else struct disk_stats dkstats; #endif diff --git a/include/linux/kexec.h b/include/linux/kexec.h index c356b6914ff..03e8e8dbc57 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -199,7 +199,7 @@ extern struct kimage *kexec_crash_image; */ extern struct resource crashk_res; typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4]; -extern note_buf_t *crash_notes; +extern note_buf_t __percpu *crash_notes; extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4]; extern size_t vmcoreinfo_size; extern size_t vmcoreinfo_max_size; diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 7874201a355..41acd4bf766 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -301,7 +301,7 @@ struct zone { unsigned long min_unmapped_pages; unsigned long min_slab_pages; #endif - struct per_cpu_pageset *pageset; + struct per_cpu_pageset __percpu *pageset; /* * free areas of different sizes */ diff --git a/include/linux/module.h b/include/linux/module.h index 7e74ae0051c..dd618eb026a 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -365,7 +365,7 @@ struct module struct module_ref { int count; - } *refptr; + } __percpu *refptr; #endif #ifdef CONFIG_CONSTRUCTORS diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h index a7684a51399..9bd103c844e 100644 --- a/include/linux/percpu_counter.h +++ b/include/linux/percpu_counter.h @@ -21,7 +21,7 @@ struct percpu_counter { #ifdef CONFIG_HOTPLUG_CPU struct list_head list; /* All percpu_counters are on a list */ #endif - s32 *counters; + s32 __percpu *counters; }; extern int percpu_counter_batch; diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 4765d97dcaf..41eedccc962 100644 --- a/include/linux/srcu.h +++ b/include/linux/srcu.h @@ -33,7 +33,7 @@ struct srcu_struct_array { struct srcu_struct { int completed; - struct srcu_struct_array *per_cpu_ref; + struct srcu_struct_array __percpu *per_cpu_ref; struct mutex mutex; }; -- cgit v1.2.3 From 003cb608a2533d0927a83bc4e07e46d7a622eda9 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 2 Feb 2010 14:39:01 +0900 Subject: percpu: add __percpu sparse annotations to fs Add __percpu sparse annotations to fs. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: Tejun Heo Cc: "Theodore Ts'o" Cc: Trond Myklebust Cc: Alex Elder Cc: Christoph Hellwig Cc: Alexander Viro --- include/linux/mount.h | 2 +- include/linux/nfs_fs_sb.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/mount.h b/include/linux/mount.h index 5d527536486..b5f43a34ef8 100644 --- a/include/linux/mount.h +++ b/include/linux/mount.h @@ -66,7 +66,7 @@ struct vfsmount { int mnt_pinned; int mnt_ghosts; #ifdef CONFIG_SMP - int *mnt_writers; + int __percpu *mnt_writers; #else int mnt_writers; #endif diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index 34fc6be5bfc..6a2e44fd75e 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -105,7 +105,7 @@ struct nfs_server { struct rpc_clnt * client; /* RPC client handle */ struct rpc_clnt * client_acl; /* ACL RPC client handle */ struct nlm_host *nlm_host; /* NLM client handle */ - struct nfs_iostats * io_stats; /* I/O statistics */ + struct nfs_iostats __percpu *io_stats; /* I/O statistics */ struct backing_dev_info backing_dev_info; atomic_long_t writeback; /* number of writeback pages */ int flags; /* various flags */ -- cgit v1.2.3 From a29d8b8e2d811a24bbe49215a0f0c536b72ebc18 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 2 Feb 2010 14:39:15 +0900 Subject: percpu: add __percpu sparse annotations to what's left Add __percpu sparse annotations to places which didn't make it in one of the previous patches. All converions are trivial. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: Tejun Heo Acked-by: Borislav Petkov Cc: Dan Williams Cc: Huang Ying Cc: Len Brown Cc: Neil Brown --- include/acpi/processor.h | 2 +- include/linux/dmaengine.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/acpi/processor.h b/include/acpi/processor.h index 0ea5ef4eb6a..477544fd8e9 100644 --- a/include/acpi/processor.h +++ b/include/acpi/processor.h @@ -238,7 +238,7 @@ struct acpi_processor_errata { extern int acpi_processor_preregister_performance(struct acpi_processor_performance - *performance); + __percpu *performance); extern int acpi_processor_register_performance(struct acpi_processor_performance *performance, unsigned int cpu); diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 78784982b33..21fd9b7c6a4 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -162,7 +162,7 @@ struct dma_chan { struct dma_chan_dev *dev; struct list_head device_node; - struct dma_chan_percpu *local; + struct dma_chan_percpu __percpu *local; int client_count; int table_count; void *private; -- cgit v1.2.3