From 9cf64d6c35c62c34531273aadc2bfc0e0606fd77 Mon Sep 17 00:00:00 2001 From: glebius Date: Mon, 8 Apr 2013 19:40:53 +0000 Subject: Merge from projects/counters: counter(9). Introduce counter(9) API, that implements fast and raceless counters, provided (but not limited to) for gathering of statistical data. See http://lists.freebsd.org/pipermail/freebsd-arch/2013-April/014204.html for more details. In collaboration with: kib Reviewed by: luigi Tested by: ae, ray Sponsored by: Nginx, Inc. --- sys/amd64/include/counter.h | 51 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 sys/amd64/include/counter.h (limited to 'sys/amd64') diff --git a/sys/amd64/include/counter.h b/sys/amd64/include/counter.h new file mode 100644 index 0000000..3ed5f76 --- /dev/null +++ b/sys/amd64/include/counter.h @@ -0,0 +1,51 @@ +/*- + * Copyright (c) 2012 Konstantin Belousov + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#ifndef __MACHINE_COUNTER_H__ +#define __MACHINE_COUNTER_H__ + +#include + +extern struct pcpu __pcpu[1]; + +#define counter_enter() do {} while (0) +#define counter_exit() do {} while (0) + +#define counter_u64_add_protected(c, i) counter_u64_add(c, i) + +static inline void +counter_u64_add(counter_u64_t c, int64_t inc) +{ + + __asm __volatile("addq\t%1,%%gs:(%0)" + : + : "r" ((char *)c - (char *)&__pcpu[0]), "r" (inc) + : "memory", "cc"); +} + +#endif /* ! __MACHINE_COUNTER_H__ */ -- cgit v1.1