Introduce generic support for this_cpu_add_return etc. The fallback is to realize these operations with simpler __this_cpu_ops. Reviewed-by: Tejun Heo Reviewed-by: Mathieu Desnoyers Signed-off-by: Christoph Lameter --- include/linux/percpu.h | 77 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) Index: linux-2.6/include/linux/percpu.h =================================================================== --- linux-2.6.orig/include/linux/percpu.h 2010-11-29 10:19:28.000000000 -0600 +++ linux-2.6/include/linux/percpu.h 2010-11-29 10:24:57.000000000 -0600 @@ -240,6 +240,25 @@ extern void __bad_size_call_parameter(vo pscr_ret__; \ }) +#define __pcpu_size_call_return2(stem, pcp, ...) \ +({ \ + typeof(pcp) ret__; \ + __verify_pcpu_ptr(&(pcp)); \ + switch(sizeof(pcp)) { \ + case 1: ret__ = stem##1(pcp, __VA_ARGS__); \ + break; \ + case 2: ret__ = stem##2(pcp, __VA_ARGS__); \ + break; \ + case 4: ret__ = stem##4(pcp, __VA_ARGS__); \ + break; \ + case 8: ret__ = stem##8(pcp, __VA_ARGS__); \ + break; \ + default: \ + __bad_size_call_parameter();break; \ + } \ + ret__; \ +}) + #define __pcpu_size_call(stem, variable, ...) \ do { \ __verify_pcpu_ptr(&(variable)); \ @@ -529,6 +548,64 @@ do { \ # define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val)) #endif +#define _this_cpu_generic_add_return(pcp, val) \ +({ \ + typeof(pcp) ret__; \ + preempt_disable(); \ + __this_cpu_add(pcp, val); \ + ret__ = __this_cpu_read(pcp); \ + preempt_enable(); \ + ret__; \ +}) + +#ifndef this_cpu_add_return +# ifndef this_cpu_add_return_1 +# define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val) +# endif +# ifndef this_cpu_add_return_2 +# define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val) +# endif +# ifndef this_cpu_add_return_4 +# define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val) +# endif +# ifndef this_cpu_add_return_8 +# define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val) +# endif +# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) +#endif + +#define this_cpu_sub_return(pcp, val) this_cpu_add_return(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_generic_add_return(pcp, val) \ +({ \ + typeof(pcp) ret__; \ + __this_cpu_add(pcp, val); \ + ret__ = __this_cpu_read(pcp); \ + ret__; \ +}) + +#ifndef __this_cpu_add_return +# ifndef __this_cpu_add_return_1 +# define __this_cpu_add_return_1(pcp, val) __this_cpu_generic_add_return(pcp, val) +# endif +# ifndef __this_cpu_add_return_2 +# define __this_cpu_add_return_2(pcp, val) __this_cpu_generic_add_return(pcp, val) +# endif +# ifndef __this_cpu_add_return_4 +# define __this_cpu_add_return_4(pcp, val) __this_cpu_generic_add_return(pcp, val) +# endif +# ifndef __this_cpu_add_return_8 +# define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val) +# endif +# define __this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) +#endif + +#define __this_cpu_sub_return(pcp, val) this_cpu_add_return(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) + /* * IRQ safe versions of the per cpu RMW operations. Note that these operations * are *not* safe against modification of the same variable from another -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/