From a663ffff1d2e94a7c549a37d08ed9169ce83bdd6 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Mon, 6 Dec 2010 11:39:59 -0600 Subject: percpu: Generic support for this_cpu_add, sub, dec, inc_return Introduce generic support for this_cpu_add_return etc. The fallback is to realize these operations with simpler __this_cpu_ops. tj: - Reformatted __cpu_size_call_return2() to make it more consistent with its neighbors. - Dropped unnecessary temp variable ret__ from __this_cpu_generic_add_return(). Reviewed-by: Tejun Heo Reviewed-by: Mathieu Desnoyers Acked-by: H. Peter Anvin Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo --- include/linux/percpu.h | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) (limited to 'include/linux/percpu.h') diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 5095b834a6fb..4d593defc47d 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -240,6 +240,21 @@ extern void __bad_size_call_parameter(void); 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__; \ +}) + #define __pcpu_size_call(stem, variable, ...) \ do { \ __verify_pcpu_ptr(&(variable)); \ @@ -529,6 +544,62 @@ 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) \ +({ \ + __this_cpu_add(pcp, val); \ + __this_cpu_read(pcp); \ +}) + +#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 -- cgit v1.2.1