diff options
| -rw-r--r-- | include/linux/percpu-defs.h | 209 | ||||
| -rw-r--r-- | include/linux/percpu.h | 208 |
2 files changed, 209 insertions, 208 deletions
diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index 94cd90afadac..6710eb9555fa 100644 --- a/include/linux/percpu-defs.h +++ b/include/linux/percpu-defs.h @@ -270,5 +270,214 @@ preempt_enable(); \ } while (0) +/* + * Branching function to split up a function into a set of functions that + * are called for different scalar sizes of the objects handled. + */ + +extern void __bad_size_call_parameter(void); + +#ifdef CONFIG_DEBUG_PREEMPT +extern void __this_cpu_preempt_check(const char *op); +#else +static inline void __this_cpu_preempt_check(const char *op) { } +#endif + +#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; \ + case 4: pscr_ret__ = stem##4(variable);break; \ + case 8: pscr_ret__ = stem##8(variable);break; \ + default: \ + __bad_size_call_parameter();break; \ + } \ + pscr_ret__; \ +}) + +#define __pcpu_size_call_return2(stem, variable, ...) \ +({ \ + typeof(variable) pscr2_ret__; \ + __verify_pcpu_ptr(&(variable)); \ + switch(sizeof(variable)) { \ + case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \ + case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \ + case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \ + case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \ + default: \ + __bad_size_call_parameter(); break; \ + } \ + pscr2_ret__; \ +}) + +/* + * Special handling for cmpxchg_double. cmpxchg_double is passed two + * percpu variables. The first has to be aligned to a double word + * boundary and the second has to follow directly thereafter. + * We enforce this on all architectures even if they don't support + * a double cmpxchg instruction, since it's a cheap requirement, and it + * avoids breaking the requirement for architectures with the instruction. + */ +#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \ +({ \ + bool pdcrb_ret__; \ + __verify_pcpu_ptr(&pcp1); \ + BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \ + VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \ + VM_BUG_ON((unsigned long)(&pcp2) != \ + (unsigned long)(&pcp1) + sizeof(pcp1)); \ + switch(sizeof(pcp1)) { \ + case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \ + case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \ + case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \ + case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \ + default: \ + __bad_size_call_parameter(); break; \ + } \ + pdcrb_ret__; \ +}) + +#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; \ + case 4: stem##4(variable, __VA_ARGS__);break; \ + case 8: stem##8(variable, __VA_ARGS__);break; \ + default: \ + __bad_size_call_parameter();break; \ + } \ +} while (0) + +/* + * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com> + * + * Optimized manipulation for memory allocated through the per cpu + * 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 + * accessed by a single processor instance (the current one). + * + * The arch code can provide optimized implementation by defining macros + * for certain scalar sizes. F.e. provide this_cpu_add_2() to provide per + * cpu atomic operations for 2 byte sized RMW actions. If arch code does + * not provide operations for a scalar size then the fallback in the + * generic code will be used. + */ + +/* + * Generic percpu operations for contexts where we do not want to do + * any checks for preemptiosn. + * + * If there is no other protection through preempt disable and/or + * disabling interupts then one of these RMW operations can show unexpected + * behavior because the execution thread was rescheduled on another processor + * or an interrupt occurred and the same percpu variable was modified from + * the interrupt context. + */ +# define raw_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp)) +# define raw_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val)) +# define raw_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val)) +# define raw_cpu_sub(pcp, val) raw_cpu_add((pcp), -(val)) +# define raw_cpu_inc(pcp) raw_cpu_add((pcp), 1) +# define raw_cpu_dec(pcp) raw_cpu_sub((pcp), 1) +# define raw_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val)) +# define raw_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val)) +# define raw_cpu_add_return(pcp, val) \ + __pcpu_size_call_return2(raw_cpu_add_return_, pcp, val) +#define raw_cpu_sub_return(pcp, val) raw_cpu_add_return(pcp, -(typeof(pcp))(val)) +#define raw_cpu_inc_return(pcp) raw_cpu_add_return(pcp, 1) +#define raw_cpu_dec_return(pcp) raw_cpu_add_return(pcp, -1) +# define raw_cpu_xchg(pcp, nval) \ + __pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval) +# define raw_cpu_cmpxchg(pcp, oval, nval) \ + __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval) +# define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ + __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) + +/* + * Generic percpu operations for context that are safe from preemption/interrupts. + */ +# define __this_cpu_read(pcp) \ + (__this_cpu_preempt_check("read"),__pcpu_size_call_return(raw_cpu_read_, (pcp))) + +# define __this_cpu_write(pcp, val) \ +do { __this_cpu_preempt_check("write"); \ + __pcpu_size_call(raw_cpu_write_, (pcp), (val)); \ +} while (0) + +# define __this_cpu_add(pcp, val) \ +do { __this_cpu_preempt_check("add"); \ + __pcpu_size_call(raw_cpu_add_, (pcp), (val)); \ +} while (0) + +# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(typeof(pcp))(val)) +# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1) +# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1) + +# define __this_cpu_and(pcp, val) \ +do { __this_cpu_preempt_check("and"); \ + __pcpu_size_call(raw_cpu_and_, (pcp), (val)); \ +} while (0) + +# define __this_cpu_or(pcp, val) \ +do { __this_cpu_preempt_check("or"); \ + __pcpu_size_call(raw_cpu_or_, (pcp), (val)); \ +} while (0) + +# define __this_cpu_add_return(pcp, val) \ + (__this_cpu_preempt_check("add_return"),__pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)) + +#define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val)) +#define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1) +#define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1) + +# define __this_cpu_xchg(pcp, nval) \ + (__this_cpu_preempt_check("xchg"),__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)) + +# define __this_cpu_cmpxchg(pcp, oval, nval) \ + (__this_cpu_preempt_check("cmpxchg"),__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)) + +# define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ + (__this_cpu_preempt_check("cmpxchg_double"),__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))) + +/* + * this_cpu_*() operations are used for accesses that must be done in a + * preemption safe way since we know that the context is not preempt + * safe. Interrupts may occur. If the interrupt modifies the variable too + * then RMW actions will not be reliable. + */ +# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp)) +# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val)) +# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val)) +# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(typeof(pcp))(val)) +# define this_cpu_inc(pcp) this_cpu_add((pcp), 1) +# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1) +# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val)) +# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val)) +# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) +#define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(typeof(pcp))(val)) +#define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1) +#define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1) +# define this_cpu_xchg(pcp, nval) \ + __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval) +# define this_cpu_cmpxchg(pcp, oval, nval) \ + __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval) + +/* + * cmpxchg_double replaces two adjacent scalars at once. The first + * two parameters are per cpu variables which have to be of the same + * size. A truth value is returned to indicate success or failure + * (since a double register result is difficult to handle). There is + * very limited hardware support for these operations, so only certain + * sizes may work. + */ +# define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ + __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) + #endif /* __ASSEMBLY__ */ #endif /* _LINUX_PERCPU_DEFS_H */ diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 20b953532596..6f61b61b7996 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -129,212 +129,4 @@ extern phys_addr_t per_cpu_ptr_to_phys(void *addr); #define alloc_percpu(type) \ (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type)) -/* - * Branching function to split up a function into a set of functions that - * are called for different scalar sizes of the objects handled. - */ - -extern void __bad_size_call_parameter(void); - -#ifdef CONFIG_DEBUG_PREEMPT -extern void __this_cpu_preempt_check(const char *op); -#else -static inline void __this_cpu_preempt_check(const char *op) { } -#endif - -#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; \ - case 4: pscr_ret__ = stem##4(variable);break; \ - case 8: pscr_ret__ = stem##8(variable);break; \ - default: \ - __bad_size_call_parameter();break; \ - } \ - pscr_ret__; \ -}) - -#define __pcpu_size_call_return2(stem, variable, ...) \ -({ \ - typeof(variable) pscr2_ret__; \ - __verify_pcpu_ptr(&(variable)); \ - switch(sizeof(variable)) { \ - case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \ - case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \ - case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \ - case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \ - default: \ - __bad_size_call_parameter(); break; \ - } \ - pscr2_ret__; \ -}) - -/* - * Special handling for cmpxchg_double. cmpxchg_double is passed two - * percpu variables. The first has to be aligned to a double word - * boundary and the second has to follow directly thereafter. - * We enforce this on all architectures even if they don't support - * a double cmpxchg instruction, since it's a cheap requirement, and it - * avoids breaking the requirement for architectures with the instruction. - */ -#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \ -({ \ - bool pdcrb_ret__; \ - __verify_pcpu_ptr(&pcp1); \ - BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \ - VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \ - VM_BUG_ON((unsigned long)(&pcp2) != \ - (unsigned long)(&pcp1) + sizeof(pcp1)); \ - switch(sizeof(pcp1)) { \ - case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \ - case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \ - case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \ - case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \ - default: \ - __bad_size_call_parameter(); break; \ - } \ - pdcrb_ret__; \ -}) - -#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; \ - case 4: stem##4(variable, __VA_ARGS__);break; \ - case 8: stem##8(variable, __VA_ARGS__);break; \ - default: \ - __bad_size_call_parameter();break; \ - } \ -} while (0) - -/* - * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com> - * - * Optimized manipulation for memory allocated through the per cpu - * 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 - * accessed by a single processor instance (the current one). - * - * The first group is used for accesses that must be done in a - * preemption safe way since we know that the context is not preempt - * safe. Interrupts may occur. If the interrupt modifies the variable - * too then RMW actions will not be reliable. - * - * The arch code can provide optimized implementation by defining macros - * for certain scalar sizes. F.e. provide this_cpu_add_2() to provide per - * cpu atomic operations for 2 byte sized RMW actions. If arch code does - * not provide operations for a scalar size then the fallback in the - * generic code will be used. - */ - -# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp)) -# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val)) -# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val)) -# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(typeof(pcp))(val)) -# define this_cpu_inc(pcp) this_cpu_add((pcp), 1) -# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1) -# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val)) -# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val)) -# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) -#define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(typeof(pcp))(val)) -#define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1) -#define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1) -# define this_cpu_xchg(pcp, nval) \ - __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval) -# define this_cpu_cmpxchg(pcp, oval, nval) \ - __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval) - -/* - * cmpxchg_double replaces two adjacent scalars at once. The first - * two parameters are per cpu variables which have to be of the same - * size. A truth value is returned to indicate success or failure - * (since a double register result is difficult to handle). There is - * very limited hardware support for these operations, so only certain - * sizes may work. - */ -# define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) - -/* - * Generic percpu operations for contexts where we do not want to do - * any checks for preemptiosn. - * - * If there is no other protection through preempt disable and/or - * disabling interupts then one of these RMW operations can show unexpected - * behavior because the execution thread was rescheduled on another processor - * or an interrupt occurred and the same percpu variable was modified from - * the interrupt context. - */ -# define raw_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp)) -# define raw_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val)) -# define raw_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val)) -# define raw_cpu_sub(pcp, val) raw_cpu_add((pcp), -(val)) -# define raw_cpu_inc(pcp) raw_cpu_add((pcp), 1) -# define raw_cpu_dec(pcp) raw_cpu_sub((pcp), 1) -# define raw_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val)) -# define raw_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val)) -# define raw_cpu_add_return(pcp, val) \ - __pcpu_size_call_return2(raw_cpu_add_return_, pcp, val) -#define raw_cpu_sub_return(pcp, val) raw_cpu_add_return(pcp, -(typeof(pcp))(val)) -#define raw_cpu_inc_return(pcp) raw_cpu_add_return(pcp, 1) -#define raw_cpu_dec_return(pcp) raw_cpu_add_return(pcp, -1) -# define raw_cpu_xchg(pcp, nval) \ - __pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval) -# define raw_cpu_cmpxchg(pcp, oval, nval) \ - __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval) -# define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) - -/* - * Generic percpu operations for context that are safe from preemption/interrupts. - */ -# define __this_cpu_read(pcp) \ - (__this_cpu_preempt_check("read"),__pcpu_size_call_return(raw_cpu_read_, (pcp))) - -# define __this_cpu_write(pcp, val) \ -do { __this_cpu_preempt_check("write"); \ - __pcpu_size_call(raw_cpu_write_, (pcp), (val)); \ -} while (0) - -# define __this_cpu_add(pcp, val) \ -do { __this_cpu_preempt_check("add"); \ - __pcpu_size_call(raw_cpu_add_, (pcp), (val)); \ -} while (0) - -# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(typeof(pcp))(val)) -# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1) -# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1) - -# define __this_cpu_and(pcp, val) \ -do { __this_cpu_preempt_check("and"); \ - __pcpu_size_call(raw_cpu_and_, (pcp), (val)); \ -} while (0) - -# define __this_cpu_or(pcp, val) \ -do { __this_cpu_preempt_check("or"); \ - __pcpu_size_call(raw_cpu_or_, (pcp), (val)); \ -} while (0) - -# define __this_cpu_add_return(pcp, val) \ - (__this_cpu_preempt_check("add_return"),__pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)) - -#define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val)) -#define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1) -#define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1) - -# define __this_cpu_xchg(pcp, nval) \ - (__this_cpu_preempt_check("xchg"),__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)) - -# define __this_cpu_cmpxchg(pcp, oval, nval) \ - (__this_cpu_preempt_check("cmpxchg"),__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)) - -# define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - (__this_cpu_preempt_check("cmpxchg_double"),__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))) - #endif /* __LINUX_PERCPU_H */ |